Printer Friendly

Lung cancer genotype-based therapy and predictive biomarkers: present and future.

In 2012, it is estimated that lung cancer will cause about 29% of all cancer deaths among men and 26% of all cancer deaths among women in the United States, for a total of 160 340 deaths, more than the combined number of deaths from the next 3 most common causes of cancer deaths (colon, breast, and prostate cancers). (1) Worldwide, in 2008, lung cancer was the leading cause of cancer deaths in males and the second leading cause of cancer deaths in females, about 1 400 000, or 18% of all cancer deaths. (2) Five year survival for male lung cancer patients ranges from 6% to 14% and for female lung cancer patients ranges from 7% to 18%. (2)

For decades, the dismal prognosis of lung cancer and the limited number of treatment options have narrowed the practical impact of pathologic diagnoses on the care of lung cancer patients. (3,4) Lung cancer has been divided into 2 categories for purposes of diagnosis and treatment: small cell lung carcinoma (SCLC) and the non-small cell lung carcinomas (NSCLCs), the latter consisting of adenocarcinoma, squamous cell carcinoma, and large cell carcinoma cell types. Small cell lung carcinomas make up less than 15% of lung cancers, almost always are diagnosed in an advanced stage with metastatic disease, are treated with chemoradiation, and have a very poor survival (overall 5year survival of 6.1%). (5) Non-small cell lung carcinomas make up about 85% of lung cancers and have an overall 5year survival of 17.1%, which is dependent in large part on stage of disease. Roughly 30% of NSCLCs are diagnosed in an early stage with limited disease and treated with surgical resection, plus adjuvant therapy according to various protocols, with the intent to cure. (6-8) Nevertheless, a large percentage of these patients will die from relapse of their lung cancer, presumably most often because of undetected residual disease or metastases (5-year survival rate by clinical stage is 50% for stage IA, 43% for stage IB, 36% for stage IIA, 25% for stage IIB, and 19% for stage IIIA). (9) The majority of NSCLCs (70%) are diagnosed in a locally advanced stage (stage IIIB) or advanced stage with metastatic disease (stage IV). The 5-year survival rate by clinical stage is 7% for stage IIIB NSCLC and 2% for stage IV NSCLC. (9) Stage IV NSCLCs are traditionally treated with doublet chemotherapy that includes cisplatin or carboplatin, and may also receive radiation therapy. Virtually all lung cancer patients who initially respond to a first-line therapy progress at a later date and require second-line therapy and perhaps subsequent-line therapies depending on their clinical course, but the overwhelming majority eventually succumb to their cancer. (7,10-16)

Traditionally, the primary role of the pathologist was to differentiate SCLC from NSCLC on biopsy and/or cytology and, for the minority of NSCLCs that were potentially amenable to surgery, to examine and stage resection specimens. Of the NSCLCs, about 20% to 25% are currently diagnosed as squamous cell carcinoma and 40% to 50% are diagnosed as adenocarcinoma. Large cell carcinoma had been included as a cell type for those cancers that could not be readily typed as SCLC, adenocarcinoma, or squamous cell carcinoma, but it is now recognized that many so-called large cell carcinomas are poorly differentiated examples of the other specific cell types, most often adenocarcinoma or specific entities such as large cell neuroendocrine carcinoma. (6-8)

The World Health Organization classification of lung cancer cell types is based on resection specimens that provide abundant tissue for examination. Because the great majority of lung cancers present in an advanced stage of disease that is not potentially amenable to surgical resection, about 70% of lung cancers are diagnosed on small biopsies and/or cytology specimens and additional tissue is typically not obtained. (8) It can be very difficult to diagnose a specific cell type on some of these small samples, particularly based only on routine stains, because of the limited tissue available for examination, sampling of poorly differentiated areas, and crush and other artifacts. (17,18)

Because differentiation of SCLC from NSCLC had a potential impact on subsequent therapy, but differentiation of adenocarcinoma from squamous cell carcinoma often did not, from a practical perspective, attempting to diagnose adenocarcinoma versus squamous cell carcinoma on small samples was not clinically crucial. A Lung Cancer Working Party of the United Kingdom Coordinating Committee for Cancer Research reported in 1993 that differentiation of SCLC from NSCLC was fairly reliable on small biopsies, but in some situations, where determining adenocarcinoma versus squamous cell carcinoma was difficult or impossible, use of the diagnosis NSCLC, not otherwise specified, was suggested to avoid inaccuracies in diagnosis of cell type. (19) Over the years, the proportion of lung cancers diagnosed as NSCLC, not otherwise specified, has increased: for example, from 15.8% between 1989 and 1994 to 22.0% between 1995 and 2000 to 29.0% between 2001 to 2006 in the statewide California Cancer Registry. (20)

The introduction of new therapies, particularly targeted molecular therapies, in recent years has altered the traditional role of the pathologist in the care of lung cancer patients. One widely publicized change is that a diagnosis of NSCLC, not otherwise specified, although unavoidable in some cases, is less satisfactory than in the past. Diagnosis of the specific cell type is now important for the selection of several of these new therapies by oncologists. (8,17,21-24) For example, in contrast to patients with squamous cell carcinoma, patients with nonsquamous NSCLC are reported to have improved survival when the new antifolate drug pemetrexed is included in their regimen. (25-28) Also, the antivascular endothelial growth factor monoclonal antibody bevacizumab was approved for patients with advanced nonsquamous NSCLC but not those with squamous cell carcinoma, who may develop pulmonary hemorrhage that is sometimes life threatening when treated with bevacizumab. (29-33) As discussed further below, for the clinically validated lung cancer molecular targeted therapies and their corresponding predictive biomarkers, there is a strong association with specific cell type. (3,4,8,24,34-43) The same appears to be true for a number of the targeted therapies under investigation. For these reasons, pathologists are now strongly encouraged to diagnose adenocarcinoma versus squamous cell carcinoma on lung cancer biopsies and cytology specimens, and the diagnosis of NSCLC, not otherwise specified, is to be avoided when possible. * The use of immunostains may assist the diagnosis of specific cell type in cases where the cell type cannot be determined from the routinely stained slides. (8,17,21-24) As explained in subsequent sections, the advent of molecular targeted therapies and the need for predictive biomarker testing has introduced additional changes to the traditional role of the pathologist in the management of lung cancer patients.


Epidermal Growth Factor Receptor

Epidermal growth factor receptor (EGFR) is a member of the HER/ErbB family of cell surface receptor tyrosine kinases that controls intracellular signaling pathways that regulate cell proliferation and apoptosis. (3,35-40,45,46) During the first several years of the 21st century, a first generation of oral, selective, reversible EGFR tyrosine kinase inhibitors (TKIs), gefitinib (Iressa; AstraZeneca, London, United Kingdom) and erlotinib (Tarceva; Genentech, South San Francisco, California, and OSI Pharmaceuticals, Long Island, New York), were investigated in clinical trials of patients with advanced NSCLC. (47-57) Beginning in 2004, somatic mutations in the EGFR gene were identified as driver mutations causing oncogene addiction of a percentage of NSCLCs, making them likely to respond to EGFR TKI therapy. (58-60)

Therefore, this first generation of EGFR TKIs were found to be of limited value in treating unselected NSCLC patients in early clinical trials but had a significant response rate (RR), improved median progression-free survival (PFS), and improved overall survival in NSCLC patients with activating EGFR mutations. (61-69) In 2009, Tony Mok and colleagues (70,71) reported results of the IRESSA Pan-Asia Study, which demonstrated that patients with EGFR mutation-positive NSCLC had a better RR and PFS with gefitinib therapy compared with conventional chemotherapy. In this clinical trial, patients whose NSCLC lacked EGFR mutations had better RR and PFS with conventional chemotherapy than with gefitinib therapy. In 2010, 2 other clinical trials, WJTOG340572 and NEJ002, (73) confirmed better RR and PFS with gefitinib compared with conventional chemotherapy in patients with EGFR mutation-positive NSCLC. Clinical trials of erlotinib versus conventional chemotherapy in patients with EGFR mutation-positive NSCLC such as the OPTIMAL study (74) and EURTAC study (75) have found similar results for erlotinib.

The first-generation EGFR TKIs have been found to be useful as first-line, second-line, or subsequent-line therapies in advanced NSCLC with activating EGFR mutations. (69,76-86) No overall survival advantage for EGFR TKIs over conventional chemotherapy was demonstrated in these clinical trials, but presumably this is because of patient crossover to EGFR TKI therapy during the clinical trials. (69) Whether or not patients with early-stage NSCLC, those that might be potentially amenable to surgical resection but often later die from their cancer, will benefit from EGFR TKI therapy remains to be elucidated. (87,88) A major issue with first-generation reversible EGFR TKI therapy is the eventual development of resistance to the drugs and relapse of the cancer in patients who initially respond to the drugs. (89-91) This is explored in greater detail below.

The observation that activating EGFR mutations are a predictive biomarker for response to EGFR TKI therapy introduced a new role for pathologists in precision medicine of lung cancer patients. Two mutations account for 90% of the activating EGFR mutations, short in-frame mutations in exon 19 and the L858R point mutation in exon 21, but there are a number of less frequent EGFR mutations that are also clinically relevant. ([dagger]) Multiplex testing allows simultaneous detection of multiple EGFR mutations, not just the major 2.

The frequency of EGFR mutations in lung cancers ranges up to 32% in East Asians, ranges from 7% to 15% in Caucasians, and occurs in about 2% of African Americans. (94-96) It is estimated that there are 30 000 new cases of EGFR mutation-positive NSCLC in the United States each year. (1,69,97) Activating EGFR mutations are more common in NSCLCs from women than men, from never smokers than former or current smokers, and from Asian than other ethnic groups. The frequency of EGFR mutations in NSCLC in East Asian women who have never smoked is very high, as high as 50. ([double dagger]) However, although the demographic associations may suggest the likelihood of EGFR mutations in tumors from those patients who fit the demographic profile, use of these criteria alone would exclude too many patients who do not meet these demographic criteria, but might benefit from EGFR TKI therapy. (34,98)

The best criterion for selecting NSCLCs that should be sent for EGFR mutation testing is cell type, a diagnosis that is dependent upon the pathologist. Throughout the literature, EGFR mutations are mostly detected in adenocarcinomas. ([section]) Based on recent studies, it seems likely that many EGFR mutation-positive lung cancers given a nonadenocarcinoma diagnosis in older studies may have been misdiagnosed adenocarcinomas. As already discussed, for poorly differentiated NSCLC, additional studies such as immunohistochemistry may be needed to make an accurate diagnosis of cell type. (8,17,21-24) Many tumors previously called large cell carcinomas are now known to be specific cell types, mostly poorly differentiated adenocarcinomas. Also, it may be difficult to differentiate a solid-pattern adenocarcinoma from a squamous cell carcinoma based on routine histology. Even with special studies, a few lung tumors cannot be classified as a specific cell type. (8,17,21-24) In addition, adenosquamous carcinomas make up about 1% of lung cancers and have at least a 10% adenocarcinoma component and at least a 10% squamous cell carcinoma component. These rare tumors may have EGFR mutations and respond to EGFR TKI therapy. (100)

Although EGFR mutations have been reported in less than 1% of squamous cell carcinomas, it is possible that these are also misdiagnosed adenocarcinomas. Rekhtman et al (101) looked at this issue in a large series of lung cancers. Upon further workup of 16 tumors initially diagnosed as squamous cell carcinomas that had EGFR/KRAS mutations, they found that 10 (63%) were adenosquamous carcinomas and 5 (31%) were poorly differentiated adenocarcinomas that morphologically mimicked squamous cell carcinomas (adenocarcinomas with squamoid morphology); 1 case (6%) had no follow-up. Although it is likely that some investigators will continue to report EGFR mutations in NSCLCs other than adenocarcinoma, there is no doubt that the association between adenocarcinoma cell type and EGFR mutations is very strong and that misdiagnosed adenocarcinomas should be ruled out before acknowledging cell type exceptions.

Patients who initially respond to first-generation EGFR TKIs eventually develop resistance to the drug and relapse while still under EGFR TKI therapy. (89-91) A clinical definition of acquired resistance to EGFR TKI therapy is used in many clinical trials. The criteria consist of previous treatment with a single-agent EGFR TKI; either or both of lung cancer with an EGFR mutation associated with TKI sensitivity or objective clinical benefit from treatment with an EGFR TKI; systemic progression of disease while on continuous treatment with gefitinib or erlotinib within the last 30 days; and no intervening systemic therapy between cessation of gefitinib or erlotinib and initiation of new therapy. (90) Resistance to EGFR TKIs can be acquired by several mechanisms, most notably secondary mutations in the EGFR gene. The lung cancer may develop an EGFR T790M mutation, which causes about 50% of cases of acquired resistance to first-generation reversible EGFR TKIs. (89,91,102-105) It should be noted that T790M mutations may develop in lung cancers that have not been treated with EGFR TKIs. Other EGFR mutations, such as T854A, D761Y, and L747S, have also been reported to cause acquired resistance to first-generation EGFR TKIs. (102,104,106) Secondary overexpression and/or amplification of the receptor tyrosine kinase c-MET or its ligand, hepatocyte growth factor, is associated with about 18% of cases of acquired resistance to EGFR TKIs by activating the HER3/ERBB3 pathway or causing secondary KRAS activation. (103,107-110) Less frequent causes of acquired resistance to EGFR TKIs include acquired mutations of phosphatidylinositol-3-kinase (PI3K), transformation to small cell lung cancer, epithelial to mesenchymal transition, and KRAS mutations. (69.89)

EGFR mutations predict response to EGFR TKI therapy and, therefore, EGFR mutation testing is the basis for selecting patients for EGFR therapy. There are multiple EGFR mutation assays available, but because tumor samples may be very small and some relevant mutations may be uncommon, sensitive tests that can detect mutations in specimens with as few as 10% malignant cells are preferred. (46,93,111-124) Multiplex platforms offer advantages of simultaneous investigation of multiple mutations at one time. Epidermal growth factor receptor polysomy and amplification are associated with the presence of EGFR mutations, but in clinical trials EGFR polysomy and amplification do not predict response to EGFR TKI therapy nearly as well as EGFR mutation. ([parallel]) Therefore, EGFR fluorescence in situ hybridization (FISH) is not as reliable for selecting patients for EGFR TKI therapy. Traditional EGFR immunohistochemistry is not mutation specific and, therefore, not useful as a predictive biomarker test for EGFR TKI therapy. ([paragraph]) New EGFR mutation-specific antibodies and possible new roles for EGFR FISH and EGFR immunohistochemistry are discussed in a later section.

KRAS mutation testing has an established role in selecting EGFR antibody therapy for metastatic colon cancer, but the role of KRAS mutation testing in EGFR therapy is less clear for NSCLC. Although KRAS mutations and EGFR mutations are usually mutually exclusive in NSCLC, clinical trials have not yet confirmed a predictive value for KRAS testing for determining whether or not to give EGFR TKI or EGFR antibody therapy in NSCLC. However, some laboratories perform KRAS testing as an early step in an algorithm to exclude the need to test for other biomarkers, including EGFR, if KRAS mutation is positive. (38,69,85,93,128-131)

Anaplastic Lymphoma Kinase

In 2007, a new fusion oncogene, the echinoderm microtubule-associated proteinlike 4 (EML4) anaplastic lymphoma kinase (ALK) fusion tyrosine kinase, was described in NSCLC. (132) EML4-ALK is an oncogenic driver and activates downstream signaling pathways. Non-small cell lung carcinoma cells become addicted to EML4-ALK, making it a potential target for ALK TKIs. In NSCLC, there are multiple variants of the EML4-ALK fusion, and ALK may sometimes have other fusion partners such as TFG and KIF5B. (133-136) Anaplastic lymphoma kinase rearrangements are associated with younger patient age, never or light smokers, and adenocarcinoma histology. (137-141) The general frequency of ALK fusion genes is about 4% of adenocarcinomas, but frequency of ALK fusion genes has been reported to be 13.7% or even higher in advanced stage adenocarcinomas in never smokers. (69,140-143) It is estimated that there are about 10 000 new cases of ALK fusion genepositive NSCLC in the United States each year. (1,69,97) Cytogenetic methods such as FISH are best for identifying these chromosomal rearrangements. Reverse transcriptase polymerase chain reaction (RT-PCR) may miss fusion variants that are not specifically tested for. (142,144-146) New methods for ALK detection are discussed later.

Early clinical trials of the first-generation ALK TKI crizotinib produced improved RR and PFS in ALK-positive NSCLC. (141,142,144-147) This led to accelerated approval of crizotinib or Xalkori (Pfizer, New York, New York) by the Food and Drug Administration for treatment of advanced NSCLC with ALK rearrangements. The US Food and Drug Administration also approved a specific companion test (Vysis ALK Break-Apart FISH Probe Kit; Abbott Molecular, Des Plaines, Illinois) to select patients for therapy with Xalkori. (148-151)

As with EGFR TKIs, patients receiving crizotinib relapse within a year because of acquired resistance. Acquired resistance to crizotinib is due to secondary mutations in the ALK tyrosine kinase domain in about one-fourth of cases, ALK gene amplification, amplification of KIT, aberrant activation of other kinases, and increased autophosphorylation of EGFR. Multiple resistance mechanisms may develop simultaneously in one tumor. (152-155)


Detection of predictive biomarkers (EGFR mutations and ALK fusion genes) is the most reliable basis for selecting NSCLC patients who are likely to respond to selective first generation TKIs. (#) The pathologist has a crucial role in the preanalytic steps before the tests are performed in a molecular diagnostics laboratory.

The literature indicates that many types of tumor samples can be used for predictive biomarker testing, including formalin-fixed, paraffin-embedded tissue, fresh tissue, and frozen tissue. Fortunately, because the only tissue ordinarily obtained for 70% of lung cancers is small biopsies and/or cytology specimens, these types of small specimens are amenable to biomarker testing, including transbronchial biopsies, needle biopsies, aspirates, cell blocks, direct smears, and touch preparations. (157-166) Whether or not to do reflex testing in which all NSCLCs or all adenocarcinomas are automatically sent for biomarker testing is currently a local decision, but is likely to increase in frequency. (87,167)

It is the responsibility of the pathologist to select the tissue sample that is to be submitted for biomarker testing. The pathologist must differentiate cancer from noncancer and viable tissue from nonviable tissue and, where applicable, select a representative block from several blocks for submission to the molecular diagnostics laboratory. Adenocarcinoma cell type is a clear indication to send a tumor specimen for predictive biomarker testing, and it is the pathologist who makes this diagnosis. Small biopsies and cytology specimens in which a diagnosis of adenocarcinoma can be neither confirmed nor excluded, including when other cell types such as squamous cell carcinoma are identified, are more problematic. A decision may be made to send these for biomarker testing even if adenocarcinoma can not be confirmed. Whether or not cell subtypes within a tumor should be selected for specific biomarker testing is controversial, but certainly not yet confirmed. However, subtypes may be selected for testing as part of a clinical trial or other study. **


Need for New Targeted Therapies and Predictive Biomarker Tests

The clinical need for new predictive biomarker tests is driven by the limitations of the currently available molecular targeted therapies: (1) Current clinically validated targets, EGFR and ALK, are present in only a minority of lung cancers. As discussed previously, EGFR mutations and ALK rearrangements are largely restricted to adenocarcinomas, about 15% and 4%, respectively. Presence of one driver mutation in a lung cancer often excludes others, so that other target mutations may be present in lung cancers that are negative for EGFR mutations and ALK rearrangements. (69,94-96,140-143) Therefore, identification of additional validated targets is needed for SCLCs, squamous cell carcinomas, and the 80% or so of adenocarcinomas that are not positive for EGFR mutation or ALK rearrangement. (2) Acquired resistance to currently available targeted therapies eventually develops. Over time, alterations in the cancer genome, particularly the emergence of secondary mutations that bestow resistance to an EGFR TKI or crizotinib, confer resistance to a tumor that was previously susceptible to these agents. ([dagger])([dagger]) Therefore, druggable targets are needed for lung cancers that develop resistance to current first-generation EGFR or ALK inhibition therapies. Strategies to address these needs include a mixture of (1) second-generation drugs directed at targets that have become resistant to first-generation drugs, (2) clinical validation of drugs that act on other potential molecular targets in lung cancers, and (3) inhibition of more than one target in a cancer by using multiple agents to impact multiple targets or by using single agents that act on more than one target. (172-179) All of these approaches have implications for the future role of the pathologist in personalized health care of lung cancer patients.

Second-Generation TKIs and Testing for Resistance Mutations

As discussed previously, pulmonary adenocarcinomas that are initially responsive to first-generation reversible EGFR TKIs eventually develop acquired resistance due to one or more of several possible mechanisms. Several second-generation drugs are under investigation and some are in advanced clinical trials. These second-generation drugs are higher-affinity, irreversible EGFR tyrosine kinase blockers that also inhibit HER2 and sometimes HER4 and may have modest activity against T790M or other mutations that cause acquired resistance to first-generation EGFR TKIs. (172,173,180-184)

Afatinib (BIBW2992; Boehringer Ingelheim, Ingelheim, Germany) binds irreversibly to EGFR, HER2 and HER4, including receptors with the T790M mutation. Clinical trials of afatinib have found modest results in patients with advanced pulmonary adenocarcinoma who progressed after receiving first-generation EGFR TKIs, but ongoing clinical trials may define a role for afatinib as first-line therapy for lung cancers with activating EGFR mutations. (173,181,184-187) Other second-generation ERBB family blockers are also under investigation, (172,173) including dacomitinib (183,188,189) and XL647. (190-192)

From the pathologist's perspective, the growing number of treatment options may create a need to rebiopsy and repeat EGFR testing during the course of a lung cancer patient's treatment. This permits monitoring for the development of mutations that may impact response to the patient's current therapy and warrant a change to a different drug. Not only might rebiopsy/repeat testing be needed after the patient relapses, but a surveillance protocol could conceivably screen for the early detection of acquired mutations such as T790M before significant clinical deterioration, when an alteration in drugs might be most effective. (193,194) A similar situation exists for acquired resistance to the first-generation ALK TKI crizotinib, and investigations are underway for second-generation ALK TKIs. (154)

Cetuximab and EGFR IHC and EGFR FISH

Cetuximab (Erbitux; Bristol-Myers Squibb, New York, New York, and Eli Lilly and Company, Indianapolis, Indiana) is an anti-EGFR immunoglobulin G1 monoclonal antibody that is currently undergoing clinical trials for lung cancer therapy. (195) The First Line Erbitux in Lung Cancer clinical trials produced modest results for advanced NSCLC patients treated with cetuximab and chemotherapy. However, subgroup analysis of the First Line Erbitux in Lung Cancer phase III trial found that high EGFR expression based on an immunohistochemistry score of 200 or more using the Dako pharmDx kit (Glostrup, Denmark) was associated with increased overall survival in patients receiving first-line chemotherapy plus cetuximab in patients with advanced NSCLC compared with chemotherapy alone. (196-198) The Southwest Oncology Group study SO342 of advanced NSCLC patients receiving cetuximab plus chemotherapy found a doubling of median PFS among EGFR FISH-positive patients compared with EGFR FISH-negative patients. (199) The Southwest Oncology Group phase III trial SO819 is prospectively evaluating both therapeutic response to cetuximab in advanced NSCLC patients and EGFR FISH as a predictive biomarker for cetuximab response in these patients. (200) Therefore, although EGFR mutation testing is recommended as the best predictive biomarker test for EGFR TKIs, in the future, EGFR IHC and EGFR FISH may prove to be preferred predictive biomarker tests for cetuximab therapy for lung cancer. FISH and, especially, IHC are conventional techniques familiar to surgical pathologists and are more likely to be available in pathology laboratories that lack their own molecular diagnostics laboratory.

Genotype-Based Therapy Under Investigation

The search for driver mutations that can serve as targets for currently available or investigational new drugs has identified a number of candidate targets. Most kinase inhibitors can inhibit multiple kinase targets, and the use of agents that can simultaneously inhibit several targets is one approach to circumvent acquired resistance.

An example of a drug that inhibits multiple tyrosine kinases is crizotinib, which inhibits ALK, MET, RON, and ROS1. (201-203) Already Food and Drug Administration--approved for anti-ALK therapy, crizotinib is likely to find uses in inhibiting other targets. Similar to ALK, ROS1 rearrangements are found in a small subset of pulmonary adenocarcinomas and have a tendency to occur in patients who are younger and never smokers. ROS1 fusion genes are detected in general by FISH, and specific fusion partners are detected by RT-PCR, including CD74-ROS1, SLC34A22ROS1, and FIG-ROS1; an antibody for immunohistochemistry has also been described. Preliminary studies show that crizotinib will be clinically useful in treating NSCLC with ROS1 fusion genes. (202,204-207)

The KIF5B-RET fusion gene has been reported in 1% to 2% of pulmonary adenocarcinomas and is a prospective target of the RET TKI vandetanib. (208-212)

Overexpression and/or amplification of the receptor tyrosine kinase c-MET or its ligand, hepatocyte growth factor, is associated with about 18% of cases of acquired resistance to EGFR TKIs. Several c-MET inhibitors and cMET or hepatocyte growth factor antibodies are under investigation for several types of cancer. (213) ARQ 197 or tivantinib is a TKI that targets c-MET. Tivantinib plus erlotinib is currently undergoing phase III trials in previously treated patients with locally advanced or metastatic non squamous NSCLC, referred to as the MARQUEE (Met Inhibitor ARQ 197 plus Erlotinib versus Erlotinib plus placebo in NSCLC) trial. (214,215)

Signaling in the PI3K/AKT/mTOR pathway is initiated by activation of transmembrane receptor tyrosine kinases such as EGFR or HER2, and mutations in the PI3K/AKT/mTOR pathway have been implicated in NSCLC and SCLC. A number of inhibitors of the components of the PI3K/AKT/ mTOR pathway are undergoing clinical trial for NSCLC, including RAD001 or everolimus (mTOR inhibitor), BEZ235 (PI3K/mTOR inhibitor), GDC-0941 (PI3K inhibitor), XL147 (PI3K inhibitor) and MK-2206 (AKT inhibitor). (216-227) In addition to clinical trials for NSCLC, mTOR inhibitors, including everolimus and temsirolimus, are under investigation as potential therapies for SCLC. (228-232) Other targets and their selective inhibitors may prove useful in the future, but studies are early or have not yet yielded results. Members of the IL-6/JAK/STAT pathway are potential targets for lung cancer therapy, with several agents proposed for further investigation, including enzastaurin (JAK1 inhibitor), AZD1480 (JAK 1/2 inhibitor) and NSC743380 (STAT inhibitor). (233-236) Src TKIs such as dasatinib have also undergone phase II clinical trials with modest or disappointing results. (237-239) Interestingly, although KRAS is themostfrequentlymutated oncogene in pulmonary adenocarcinomas, found in approximately 30% of tumors, no selective KRAS inhibitors that are effective have yet been identified. (240) MEK is a potential target downstream of KRAS, but phase II clinical trials of selective MEK inhibitors have had mediocre results. (241-243)

Developments in Biomarker Testing

Next-generation technologies allow for multiplexed genotyping of lung cancers to simultaneously identify the mutational status of many genes in a tumor specimen. (116-124,244-249) Many of these platforms are becoming commercially available, and, although they are expensive, this approach eliminates the need for an algorithm of sequential tests, which takes a much longer time period to complete.

Recently, antibodies specific to ALK (250-252) and EGFR (253, 254) have been under investigation, and an ALK antibody is now commercially available in the United States (ALK [D5F3] XP Rabbit mAb [Biotinylated] No. 8936; Cell Signaling Technology, Danvers, Massachusetts). Immunohistochemistry allows for direct visualization of viable cancer cells within a small biopsy or cell block section, providing a rapid, cost effective identification of immunopositivity without attempting to extract RNA or DNA from a potentially inadequate tissue sample. Immunohistochemistry also uses routine equipment and routine laboratory procedures familiar to pathologists who are not specialized in molecular diagnostics. (3,4,43)


Lung cancer remains the most significant cause of cancer death in the United States and in the world. The advent of genotype-based therapy has created great promise for lung cancer patients and the identification of predictive biomarkers to select patients for therapy has assured a vital role for pathologists in precision medicine of lung cancer. The need for druggable targets for the majority of lung cancers that do not harbor the 2 targets that are currently clinically validated and the need for additional therapies for patients whose lung cancers develop acquired resistance to first-generation TKIs are being addressed by investigation of second generation TKIs and new druggable targets. These endeavors and the development of multiplex platforms for simultaneous detection of multiple mutations and antibodies for sensitive and specific detection of predictive biomarkers promise to enhance the role of pathologists in precision medicine of lung cancer for years to come.


(1.) Siegel R, Naishadham D, Jemal A. Cancer statistics, 2012. CA Cancer J Clin. 2012; 62(1):10-29.

(2.) Youlden DR, Cramb SM, Baade PD. The international epidemiology of lung cancer: geographical distribution and secular trends. J Thorac Oncol. 2008; 3(8): 819-831.

(3.) Cagle PT, Allen TC, Dacic S, et al. Revolution in lung cancer: new challenges for the surgical pathologist. Arch Pathol Lab Med. 2011; 135(1):110 116.

(4.) Cagle PT, Dacic S. Lung cancer and the future of pathology. Arch Pathol Lab Med. 2011; 135(3):293-295.

(5.) Neal JW, Gubens MA, Wakelee HA. Current management of small cell lung cancer. Clin Chest Med. 2011; 32(4):853-863.

(6.) Ettinger DS, Akerley W, Bepler G, et al. Non-small cell lung cancer. J Natl Compr Canc Netw. 2010; 8(7):740-801.

(7.) Saintigny P, Burger JA. Recent advances in non-small cell lung cancer biology and clinical management. Discov Med. 2012; 13(71):287-297.

(8.) Travis WD, Brambilla E, Noguchi M, et al. International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society international multidisciplinary classification of lung adenocarcinoma. J Thorac Oncol. 2011; 6(2):244-285.

(9.) Goldstraw P, Crowley J, Chansky K, et al. The IASLC lung cancer staging project: proposals for the revision of the TNM stage groupings in the forthcoming (seventh) edition of the TNM classification of malignant tumours. J Thorac Oncol. 2007; 2(8):706-714.

(10.) Azzoli CG, Baker S Jr, Temin S, et al. American Society of Clinical Oncology clinical practice guideline update on chemotherapy for stage IV nonsmall-cell lung cancer. J Clin Oncol. 2009; 27(36):6251-6266.

(11.) Azzoli CG, Temin S, Aliff T, et al. 2011 focused update of 2009 American Society Of Clinical Oncology clinical practice guideline update on chemotherapy for stage IV non-small-cell lung cancer. J Clin Oncol. 2011; 29(28):3825 3831.

(12.) Bonomi M, Pilotto S, Milella M, et al. Adjuvant chemotherapy for resected non-small-cell lung cancer: future perspectives for clinical research. J Exp Clin Cancer Res. 2011; 30:115.

(13.) Delbaldo C, Michiels S, Syz N, Soria JC, Le Chevalier T, Pignon JP. Benefits of adding a drug to a single-agent or a 2-agent chemotherapy regimen in advanced non-small-cell lung cancer: a meta-analysis. JAMA. 2004; 292(4):470-484.

(14.) Heon S, Johnson BE. Adjuvant chemotherapy for surgically resected nonsmall cell lung cancer. J Thorac Cardiovasc Surg. 2012.

(15.) Novello S, Milella M, Tiseo M, et al. Maintenance therapy in NSCLC: why? to whom? which agent? J Exp Clin Cancer Res. 2011; 30:50.

(16.) Paoletti L, Pastis NJ, DenlingerCE, Silvestri GA. A decade of advances in treatment of early-stage lung cancer. Clin Chest Med. 2011; 32(4):827-838.

(17.) Sigel CS, Moreira AL, Travis WD, et al. Subtyping of non-small cell lung carcinoma: a comparison of small biopsy and cytology specimens. J Thorac Oncol. 2011; 6(11):1849-1856.

(18.) Travis WD, Rekhtman N, Riley GJ, et al. Pathologic diagnosis of advanced lung cancer based on small biopsies and cytology: a paradigm shift. J Thorac Oncol. 2010; 5(4):411-414.

(19.) Thomas JS, Lamb D, Ashcroft T, et al. How reliable is the diagnosis of lung cancer using small biopsy specimens?: report of a UKCCCR lung cancer working party. Thorax. 1993; 48(11):1135-1139.

(20.) Ou SH, Zell JA. Carcinoma NOS is a common histologic diagnosis and is increasing in proportion among non-small cell lung cancer histologies. J Thorac Oncol. 2009; 4(10):1202-1211.

(21.) Bishop JA, Teruya-Feldstein J, Westra WH, Pelosi G, Travis WD, Rekhtman N. p40 (DeltaNp63) is superior to p63 for the diagnosis of pulmonary squamous cell carcinoma. Mod Pathol. 2012;25(3):405-415.

(22.) Rekhtman N, Ang DC, Sima CS, Travis WD, Moreira AL. Immunohistochemical algorithm for differentiation of lung adenocarcinoma and squamous cell carcinoma based on large series of whole-tissue sections with validation in small specimens. Mod Pathol. 2011; 24(10):1348-1359.

(23.) Turner BM, Cagle PT, Sainz IM, Fukuoka J, Shen SS, Jagirdar J. Napsin A, a new marker for lung adenocarcinoma, is complementary and more sensitive and specific than thyroid transcription factor 1 in the differential diagnosis of primary pulmonary carcinoma: evaluation of 1674 cases by tissue microarray. Arch Pathol Lab Med. 2012; 136(2):163-171.

(24.) Langer CJ, Besse B, Gualberto A, Brambilla E, Soria JC. The evolving role of histology in the management of advanced non-small-cell lung cancer. J Clin Oncol. 2010; 28(36):5311-5320.

(25.) Ciuleanu T, Brodowicz T, Zielinski C, et al. Maintenance pemetrexed plus best supportive care versus placebo plus best supportive care for non-small-cell lung cancer: a randomised, double-blind, phase 3 study. Lancet. 2009; 374(9699): 1432-1440.

(26.) Hanna N, Shepherd FA, Fossella FV, et al. Randomized phase III trial of pemetrexed versus docetaxel in patients with non-small-cell lung cancer previously treated with chemotherapy. J Clin Oncol. 2004; 22(9):1589-1597.

(27.) Scagliotti G, Hanna N, Fossella F, et al. The differential efficacy of pemetrexed according to NSCLC histology: a review of two phase III studies. Oncologist. 2009; 14(3):253-263.

(28.) Syrigos KN, Vansteenkiste J, Parikh P, et al. Prognostic and predictive factors in a randomized phase III trial comparing cisplatin-pemetrexed versus cisplatin-gemcitabine in advanced non-small-cell lung cancer. Ann Oncol. 2010; 21(3):556-561.

(29.) Cohen MH, Gootenberg J, Keegan P, Pazdur R. FDA drug approval summary: bevacizumab (Avastin) plus carboplatin and paclitaxel as first-line treatment of advanced/metastatic recurrent nonsquamous non-small cell lung cancer. Oncologist. 2007; 12(6):713-718.

(30.) Hapani S, Sher A, Chu D, Wu S. Increased risk of serious hemorrhage with bevacizumab in cancer patients: a meta-analysis. Oncology. 2010; 79(1-2): 27-38.

(31.) Johnson DH, Fehrenbacher L, Novotny WF, et al. Randomized phase II trial comparing bevacizumab plus carboplatin and paclitaxel with carboplatin and paclitaxel alone in previously untreated locally advanced or metastatic non-small-cell lung cancer. J Clin Oncol. 2004; 22(11):2184-2191.

(32.) Sandler A, Gray R, Perry MC, et al. Paclitaxel-carboplatin alone or with bevacizumab for non-small-cell lung cancer. N Engl J Med. 2006; 355(24):2542-2550.

(33.) Sandler AB, Schiller JH, Gray R, et al. Retrospective evaluation of the clinical and radiographic risk factors associated with severe pulmonary hemorrhage in first-line advanced, unresectable non-small-cell lung cancer treated with carboplatin and paclitaxel plus bevacizumab. J Clin Oncol. 2009; 27(9):1405-1412.

(34.) Bunn PA Jr, Hirsch FR, Doebele RC, Camidge DR, Varella-Garcia M, Franklin W. Biomarkers are here to stay for clinical research and standard care. J Thorac Oncol. 2010; 5(8):1113-1115.

(35.) Chirieac LR, Dacic S. Targeted therapies in lung cancer. Surg Pathol Clin. 2010; 3(1):71-82.

(36.) Dacic S. Molecular diagnostics of lung carcinomas. Arch Pathol Lab Med. 2011; 135(5):622-629.

(37.) Dacic S. Lung carcinoma morphology or mutational profile: that is the question. Arch Pathol Lab Med. 2011; 135(10):1242-1243.

(38.) Febbo PG, Ladanyi M, Aldape KD, et al. NCCN task force report: evaluating the clinical utility of tumor markers in oncology. J Natl Compr Canc Netw. 2011; 9(suppl 5):S1-S32; quiz S33.

(39.) Hirsch FR, Wynes MW, Gandara DR, Bunn PA Jr. The tissue is the issue: personalized medicine for non-small cell lung cancer. Clin Cancer Res. 2010; 16(20):4909-4911.

(40.) Kerr KM. Personalized medicine for lung cancer: new challenges for pathology. Histopathology. 2012; 60(4):531-546.

(41.) Lam KC, Mok TS. Targeted therapy: an evolving world of lung cancer.= Respirology. 2011; 16(1):13-21.

(42.) Mok TS, Zhou Q, Leung L, Loong HH. Personalized medicine for nonsmall-cell lung cancer. Expert Rev Anticancer Ther. 2010; 10(10):1601-1611.

(43.) CaglePT, Chirieac LR. Advances in treatment of lung cancer with targeted therapy. Arch Pathol Lab Med. 2012; 136(5):504-509.

(44.) Travis WD, Rekhtman N. Pathological diagnosis and classification of lung cancer in small biopsies and cytology: Strategic management of tissue for molecular testing. Semin Respir Crit Care Med. 2011; 32(1):22-31.

(45.) Gately K, O'FlahertyJ, Cappuzzo F, Pirker R, Kerr K, O'Byrne K. The role of the molecular footprint of EGFR in tailoring treatment decisions in NSCLC. J Clin Pathol. 2012; 65(1):1-7.

(46.) Hirsch FR, Bunn PA Jr. EGFR testing in lung cancer is ready for prime time. Lancet Oncol. 2009; 10(5):432-433.

(47.) Bonomi P. Erlotinib: A new therapeutic approach for non-small cell lung cancer. Expert Opin Investig Drugs. 2003; 12(8):1395-1401.

(48.) Gelibter A, Ceribelli A, Milella M, Mottolese M, Vocaturo A, Cognetti F. Clinically meaningful response to the EGFR tyrosine kinase inhibitor gefitinib ('Iressa', ZD1839) in non small cell lung cancer. J Exp Clin Cancer Res. 2003; 22(3):481-485.

(49.) Grunwald V, Hidalgo M. Development of the epidermal growth factor receptor inhibitor tarceva (OSI-774). Adv Exp MedBiol. 2003; 532:235-246.

(50.) Herbst RS. Erlotinib (Tarceva): An update on the clinical trial program. Semin Oncol. 2003; 30(3)(suppl 7):34-46.

(51.) Herbst RS, Khuri FR, Fossella FV, et al. ZD1839 (Iressa) in non-small-cell lung cancer. Clin Lung Cancer. 2001; 3(1):27-32.

(52.) Herbst RS, Kies MS. ZD1839 (Iressa) in non-small cell lung cancer. Oncologist. 2002; 7(suppl 4):9-15.

(53.) Kris MG, Natale RB, Herbst RS, et al. Efficacy of gefitinib, an inhibitor of the epidermal growth factor receptor tyrosine kinase, in symptomatic patients with non-small cell lung cancer: arandomized trial. JAMA. 2003; 290(16):2149 2158.

(54.) Liu CY, Seen S. Gefitinib therapy for advanced non-small-cell lung cancer. Ann Pharmacother. 2003; 37(11):1644-1653.

(55.) Pallis AG, Mavroudis D, Androulakis N, et al. ZD1839, a novel, oral epidermal growth factor receptor-tyrosine kinase inhibitor, as salvage treatment in patients with advanced non-small cell lung cancer: experience from a single center participating in a compassionate use program. Lung Cancer. 2003; 40(3): 301-307.

(56.) Sandler A. Clinical experience with the HER1/EGFR tyrosine kinase inhibitor erlotinib. Oncology (Williston Park). 2003; 17(11)(suppl 12):17-22.

(57.) Yano S, Yamaguchi M, Dong RP. EGFR tyrosine kinase inhibitor "gefitinib (Iressa)" for cancer therapy. Nihon Yakurigaku Zasshi. 2003; 122(6):491-497.

(58.) Lynch TJ, Bell DW, Sordella R, et al. Activating mutations in the epidermal growth factor receptor underlying responsiveness of non-small-cell lung cancer to gefitinib. N Engl J Med. 2004; 350(21):2129-2139.

(59.) Paez JG, Janne PA, Lee JC, et al. EGFR mutations in lung cancer: correlation with clinical response to gefitinib therapy. Science. 2004; 304(5676): 1497-1500.

(60.) Pao W, Miller V, Zakowski M, et al. EGF receptor gene mutations are common in lung cancers from "never smokers" and are associated with sensitivity of tumors to gefitinib and erlotinib. Proc Natl Acad Sci USA. 2004; 101(36):13306-13311.

(61.) Blackhall FH, Rehman S, Thatcher N. Erlotinib in non-small cell lung cancer: a review. Expert Opin Pharmacother. 2005; 6(6):995-1002.

(62.) Chang AY. The role of gefitinib in the management of Asian patients with non-small cell lung cancer. Expert Opin Investig Drugs. 2008;17(3):401-411.

(63.) Costa DB, Kobayashi S, Tenen DG, Huberman MS. Pooled analysis of the prospective trials of gefitinib monotherapy for EGFR-mutant non-small cell lung cancers. Lung Cancer. 2007; 58(1):95-103.

(64.) Costa DB, Nguyen KS, Cho BC, et al. Effects of erlotinib in EGFR mutated non-small cell lung cancers with resistance to gefitinib. Clin Cancer Res. 2008; 14(21):7060-7067.

(65.) Herbst RS, Prager D, Hermann R, et al. TRIBUTE: a phase III trial of erlotinib hydrochloride (OSI-774) combined with carboplatin and paclitaxel chemotherapy in advanced non-small-cell lung cancer. J Clin Oncol. 2005; 23(25):5892-5899.

(66.) Perez-Soler R. Phase II clinical trial data with the epidermal growth factor receptor tyrosine kinase inhibitor erlotinib (OSI-774) in non-small-cell lung cancer. Clin Lung Cancer. 2004; 6(suppl 1):S20-S23.

(67.) Schettino C, Bareschino MA, Ricci V, Ciardiello F. Erlotinib: an EGF receptor tyrosine kinase inhibitor in non-small-cell lung cancer treatment. Expert Rev Respir Med. 2008; 2(2):167-178.

(68.) Wheatley-Price P, Shepherd FA. Epidermal growth factor receptor inhibitors in the treatment of lung cancer: reality and hopes. Curr Opin Oncol. 2008; 20(2):162-175.

(69.) Gaughan EM, Costa DB. Genotype-driven therapies for non-small cell lung cancer: focus on EGFR, KRAS and ALK gene abnormalities. Ther Adv Med Oncol. 2011; 3(3):113-125.

(70.) Fukuoka M, Wu YL, Thongprasert S, et al. Biomarker analyses and final overall survival results from a phase III, randomized, open-label, first-line study of gefitinib versus carboplatin/paclitaxel in clinically selected patients with advanced non-small-cell lung cancer in Asia (IPASS). J Clin Oncol. 2011; 29(21):2866-2874.

(71.) Mok TS, Wu YL, Thongprasert S, et al. Gefitinib or carboplatin-paclitaxel in pulmonary adenocarcinoma. N EnglJMed. 2009; 361(10):947-957.

(72.) Mitsudomi T, Morita S, Yatabe Y, et al. Gefitinib versus cisplatin plus docetaxel in patientswith non-small-cell lung cancer harbouring mutations of the epidermal growth factor receptor (WJTOG3405): an open label, randomised phase 3 trial. Lancet Oncol. 2010; 11(2):121-128.

(73.) Maemondo M, Inoue A, Kobayashi K, et al. Gefitinib or chemotherapy for non-small-cell lung cancer with mutated EGFR. N Engl J Med. 2010; 362(25): 2380-2388.

(74.) Zhou C, Wu YL, Chen G, et al. Erlotinib versus chemotherapy as first-line treatment for patients with advanced EGFR mutation-positive non-small-cell lung cancer (OPTIMAL, CTONG-0802): a multicentre, open-label, randomised, phase 3 study. Lancet Oncol. 2011; 12(8):735-742.

(75.) Rosell R, Carcereny E, Gervais R, et al. Erlotinib versus standard chemotherapy as first-line treatment for European patients with advanced EGFR mutation-positive non-small-cell lung cancer (EURTAC): a multicentre, open label, randomised phase 3 trial. Lancet Oncol. 2012; 13(3):239-246.

(76.) Mok TS, D'arcangelo M, Califano R. Clinical outcomes with erlotinib in patients with epidermal growth factor receptor mutation. Drugs. 2012; 72(suppl 1):3-10.

(77.) Mok TS, Wu YL, Yu CJ, et al. Randomized, placebo-controlled, phase II study of sequential erlotinib and chemotherapy as first-line treatment for advanced non-small-cell lung cancer. J Clin Oncol. 2009; 27(30):5080-5087.

(78.) Paz-Ares L, Soulieres D, Melezinek I, et al. Clinical outcomes in nonsmall-cell lung cancer patients with EGFR mutations: pooled analysis. J Cell Mol Med. 2010; 14(1-2):51-69.

(79.) Rizvi NA, Rusch V, Pao W, et al. Molecular characteristics predict clinical outcomes: Prospective trial correlating response to the EGFR tyrosine kinase inhibitor gefitinib with the presence of sensitizing mutations in the tyrosine binding domain of the EGFR gene. Clin Cancer Res. 2011; 17(10):3500-3506.

(80.) Satoh H, Inoue A, Kobayashi K, et al. Low-dose gefitinib treatment for patients with advanced non-small cell lung cancer harboring sensitive epidermal growth factor receptor mutations. J Thorac Oncol. 2011; 6(8):1413-1417.

(81.) Bria E, Milella M, Cuppone F, et al. Outcome of advanced NSCLC patients harboring sensitizing EGFR mutations randomized to EGFR tyrosine kinase inhibitors or chemotherapy as first-line treatment: a meta-analysis. Ann Oncol. 2011; 22(10):2277-2285.

(82.) Gridelli C, Ciardiello F, Gallo C, et al. First-line erlotinib followed by second-line cisplatin-gemcitabine chemotherapy in advanced non-small-cell lung cancer: the TORCH randomized trial [published online ahead of print August 20, 2012]. J Clin Oncol. 2012; 30(24):3002-3011.

(83.) Hirsch FR, Kabbinavar F, Eisen T, et al. A randomized, phase II, biomarker-selected study comparing erlotinib to erlotinib intercalated with chemotherapy in first-line therapy for advanced non-small-cell lung cancer. J Clin Oncol. 2011; 29(26):3567-3573.

(84.) Inoue A, Kobayashi K, Usui K, et al. First-line gefitinib for patients with advanced non-small-cell lung cancer harboring epidermal growth factor receptor mutations without indication for chemotherapy. J Clin Oncol. 2009; 27(9):1394 1400.

(85.) Leighl NB. Treatment paradigms for patients with metastatic non-smallcell lung cancer: First-, second-, and third-line. Curr Oncol. 2012; 19(suppl 1): S52-S58.

(86.) Milella M, Nuzzo C, Bria E, et al. EGFR molecular profiling in advanced NSCLC: a prospective phase II study in molecularly/clinically selected patients pretreated with chemotherapy. J Thorac Oncol. 2012; 7(4):672-680.

(87.) D'Angelo SP, Park B, Azzoli CG, et al. Reflex testing of resected stage I through III lung adenocarcinomas for EGFR and KRAS mutation: report on initial experience and clinical utility at a single center. J Thorac Cardiovasc Surg. 2011; 141(2):476-480.

(88.) Janjigian YY, Park BJ, Zakowski MF, et al. Impact on disease-free survival of adjuvant erlotinib or gefitinib in patients with resected lung adenocarcinomas that harbor EGFR mutations. J Thorac Oncol. 2011; 6(3):569-575.

(89.) Engelman JA, Janne PA. Mechanisms of acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors in non-small cell lung cancer. Clin Cancer Res. 2008; 14(10):2895-2899.

(90.) Jackman D, Pao W, Riely GJ, et al. Clinical definition of acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors in non small-cell lung cancer. J Clin Oncol. 2010; 28(2):357-360.

(91.) Yano S. Studies for mechanism of drug resistance to EGFR-TKI. Gan To Kagaku Ryoho. 2010; 37(8):1463-1466.

(92.) HeM, Capelletti M, Nafa K, et al. EGFR exon 19 insertions: a new family of sensitizing EGFR mutations in lung adenocarcinoma. Clin Cancer Res. 2012; 18(6):1790-1797.

(93.) Pirker R, Herth FJ, Kerr KM, et al. Consensus for EGFR mutation testing in non-small cell lung cancer: results from a European workshop. J Thorac Oncol. 2010; 5(10):1706-1713.

(94.) Mitsudomi T, Yatabe Y. Mutations of the epidermal growth factor receptor gene and related genes as determinants of epidermal growth factor receptor tyrosine kinase inhibitors sensitivity in lung cancer. Cancer Sci. 2007; 98(12): 1817-1824.

(95.) Suda K, Tomizawa K, Mitsudomi T. Biological and clinical significance of KRAS mutations in lung cancer: an oncogenic driver that contrasts with EGFR mutation. Cancer Metastasis Rev. 2010; 29(1):49-60.

(96.) Reinersman JM, Johnson ML, Riely GJ, et al. Frequency of EGFR and KRAS mutations in lung adenocarcinomas in African Americans. J Thorac Oncol. 2011; 6(1):28-31.

(97.) Jemal A, Siegel R, Xu J, Ward E. Cancer statistics, 2010. CA Cancer J Clin. 2010; 60(5):277-300.

(98.) D'Angelo SP, PietanzaMC, Johnson ML, et al. Incidence of EGFR exon 19 deletions and L858R in tumor specimens from men and cigarette smokers with lung adenocarcinomas. J Clin Oncol. 2011; 29(15):2066-2070.

(99.) Girard N, Sima CS, Jackman DM, et al. Nomogram to predict the presence of EGFR activating mutation in lung adenocarcinoma. Eur Respir J. 2012; 39(2):366-372.

(100.) Tochigi N, Dacic S, Nikiforova M, Cieply KM, Yousem SA. Adenosquamous carcinoma of the lung: a microdissection study of KRAS and EGFR mutational and amplification status in a western patient population. Am J Clin Pathol. 2011; 135(5):783-789.

(101.) Rekhtman N, Paik PK, Arcila ME, et al. Clarifying the spectrum of driver oncogene mutations in biomarker-verified squamous carcinoma of lung: lack of EGFR/KRAS and presence of PIK3CA/AKT1 mutations. Clin Cancer Res. 2012; 18(4):1167-1176.

(102.) Balak MN, Gong Y, Riely GJ, et al. Novel D761Yand common secondary T790M mutations in epidermal growth factor receptor-mutant lung adenocarcinomas with acquired resistance to kinase inhibitors. Clin Cancer Res. 2006; 12(21):6494-6501.

(103.) Chen HJ, Mok TS, Chen ZH, et al. Clinicopathologic and molecular features of epidermal growth factor receptor T790M mutation and c-MET amplification in tyrosine kinase inhibitor-resistant Chinese non-small cell lung cancer. Pathol Oncol Res. 2009; 15(4):651-658.

(104.) Costa DB, Schumer ST, Tenen DG, Kobayashi S. Differential responses to erlotinib in epidermal growth factor receptor (EGFR)-mutated lung cancers with acquired resistance to gefitinib carrying the L747S or T790M secondary mutations. J Clin Oncol. 2008; 26(7):1182-1184; author reply 1184-1186.

(105.) Sequist LV, Waltman BA, Dias-Santagata D, et al. Genotypic and histological evolution of lung cancers acquiring resistance to EGFR inhibitors. Sci Transl Med. 2011; 3(75):75ra26.

(106.) Bean J, Riely GJ, Balak M, et al. Acquired resistance to epidermal growth factor receptor kinase inhibitors associated with a novel T854A mutation in a patient with EGFR-mutant lung adenocarcinoma. Clin Cancer Res. 2008; 14(22): 7519-7525.

(107.) Bean J, Brennan C, Shih JY, et al. MET amplification occurs with or without T790M mutations in EGFR mutant lung tumors with acquired resistance to gefitinib or erlotinib. Proc Natl AcadSci U SA. 2007; 104(52):20932-20937.

(108.) Engelman JA, Zejnullahu K, Mitsudomi T, et al. MET amplification leads to gefitinib resistance in lung cancer by activating ERBB3 signaling. Science. 2007; 316(5827):1039-1043.

(109.) Yano S, Wang W, Li Q, et al. Hepatocyte growth factor induces gefitinib resistance of lung adenocarcinoma with epidermal growth factor receptor activating mutations. Cancer Res. 2008; 68(22):9479-9487.

(110.) Yano S, Yamada T, Takeuchi S, et al. Hepatocyte growth factor expression in EGFR mutant lung cancer with intrinsic and acquired resistance to tyrosine kinase inhibitors in a Japanese cohort. J Thorac Oncol. 2011; 6(12):2011-2017.

(111.) Goto K, Satouchi M, Ishii G, et al. An evaluation study of EGFR mutation tests utilized for non-small-cell lung cancer in the diagnostic setting [published online ahead of print July 9, 2012]. Ann Oncol. 2012. doi:10.1093/annonc/ mds121.

(112.) Ellison G, Donald E, Mc Walter G, et al. A comparison of ARMS and DNA sequencing for mutation analysis in clinical biopsy samples. J Exp Clin Cancer Res. 2010; 29:132.

(113.) Pennycuick A, Simpson T, Crawley D, et al. Routine EGFR and KRAS mutation analysis using COLD-PCR in non-small cell lung cancer. Int J Clin Pract. 2012; 66(8):748-752.

(114.) Sun MH, Yang F, Shen L, et al. Detection of epidermal growth factor receptor mutations in non-small-cell lung carcinoma by direct sequencing and correlations with clinicopathological characteristics and sample types. Zhonghua Bing Li Xue Za Zhi. 2011; 40(10):655-659.

(115.) Warth A, Penzel R, Brandt R, et al. Optimized algorithm for Sanger sequencing-based EGFR mutation analyses in NSCLC biopsies. Virchows Arch. 2012; 460(4):407-414.

(116.) Bonanno L, Favaretto A, Rugge M, Taron M, Rosell R. Role of genotyping in non-small cell lung cancer treatment: current status. Drugs. 2011; 71(17): 2231-2246.

(117.) Corless CL, Spellman PT. Tackling formalin-fixed, paraffin-embedded tumor tissue with next-generation sequencing. Cancer Discov. 2012; 2(1):23-24.

(118.) Cronin M, Ross JS. Comprehensive next-generation cancer genome sequencing in the era of targeted therapy and personalized oncology. Biomark Med. 2011; 5(3):293-305.

(119.) Lin CH, Yeh KT, Chang YS, Hsu NC, Chang JG. Rapid detection of epidermal growth factor receptor mutations with multiplex PCR and primer extension in lung cancer. J BiomedSci. 2010; 17:37.

(120.) Miller S. A SNaPshot into a tumor's genotype: rapid, comprehensive genotyping possible in routine clinical practice. Bioanalysis. 2011; 3(24):2705.

(121.) Porteous M. Insights from next generation sequencing of the cancer genome. J R Coll Physicians Edinb. 2011; 41(4):323.

(122.) Rizzo JM, Buck MJ. Key principles and clinical applications of "next generation" DNA sequencing. Cancer Prev Res (Phila). 2012; 5(7):887-900.

(123.) Sequist LV, Heist RS, Shaw AT, et al. Implementing multiplexed genotyping of non-small-cell lung cancers into routine clinical practice. Ann Oncol. 2011; 22(12):2616-2624.

(124.) Su Z, Dias-Santagata D, Duke M, et al. A platform for rapid detection of multiple oncogenic mutations with relevance to targeted therapy in non-small cell lung cancer. J Mol Diagn. 2011; 13(1):74-84.

(125.) Bell DW, Lynch TJ, Haserlat SM, et al. Epidermal growth factor receptor mutations and gene amplification in non-small-cell lung cancer: molecular analysis of the IDEAL/INTACT gefitinib trials. J Clin Oncol. 2005; 23(31):8081 8092.

(126.) Cappuzzo F. EGFR FISH versus mutation: different tests, different end points. Lung Cancer. 2008; 60(2):160-165.

(127.) Hirsch FR, Varella-Garcia M, Dziadziuszko R, et al. Fluorescence in situ hybridization subgroup analysis of TRIBUTE, a phase III trial of erlotinib plus carboplatin and paclitaxel in non-small cell lung cancer. Clin Cancer Res. 2008; 14(19):6317-6323.

(128.) Califano R, Landi L, Cappuzzo F. Prognostic and predictive value of KRAS mutations in non-small cell lung cancer. Drugs. 2012; 72(suppl 1):28-36.

(129.) Metro G, Chiari R, Duranti S, et al. Impact of specific mutant KRAS on clinical outcome of EGFR-TKI-treated advanced non-small cell lung cancer patientswith an EGFR wild type genotype [published online ahead of print July 4, 2012]. Lung Cancer. 2012. doi:10.1016/j.lungcan.2012.06.005.

(130.) Roberts PJ, Stinchcombe TE, Der CJ, Socinski MA. Personalized medicine in non-small-cell lung cancer: is KRAS a useful marker in selecting patients for epidermal growth factor receptor-targeted therapy? J Clin Oncol. 2010; 28(31): 4769-4777.

(131.) Ellis PM, Blais N, Soulieres D, et al. A systematic review and Canadian consensus recommendations on the use of biomarkers in the treatment of non small cell lung cancer. J Thorac Oncol. 2011; 6(8):1379-1391.

(132.) Soda M, Choi YL, Enomoto M, et al. Identification of the transforming EML4-ALK fusion gene in non-small-cell lung cancer. Nature. 2007; 448(7153): 561-566.

(133.) Rikova K, Guo A, Zeng Q, et al. Global survey of phosphotyrosine signaling identifies oncogenic kinases in lung cancer. Cell. 2007;131(6):1190 1203.

(134.) Choi YL, Takeuchi K, Soda M, et al. Identification of novel isoforms of the EML4-ALK transforming gene in non-small cell lung cancer. Cancer Res. 2008; 68(13):4971-4976.

(135.) Takeuchi K, Choi YL, Togashi Y, et al. KIF5B-ALK, a novel fusion oncokinase identified by an immunohistochemistry-based diagnostic system for ALK-positive lung cancer. Clin Cancer Res. 2009; 15(9):3143-3149.

(136.) Togashi Y, Soda M, Sakata S, et al. KLC1-ALK: a novel fusion in lung cancer identified using a formalin-fixed paraffin-embedded tissue only. PLoS One. 2012; 7(2):e31323.

(137.) Inamura K, Takeuchi K, Togashi Y, et al. EML4-ALK lung cancers are characterized by rare other mutations, a TTF-1 cell lineage, an acinar histology, and young onset. Mod Pathol. 2009; 22(4):508-515.

(138.) Inamura K, Takeuchi K, Togashi Y, et al. EML4-ALK fusion is linked to histological characteristics in a subset of lung cancers. J Thorac Oncol. 2008; 3(1): 13-17.

(139.) Koh Y, Kim DW, Kim TM, et al. Clinicopathologic characteristics and outcomes of patients with anaplastic lymphoma kinase-positive advanced pulmonary adenocarcinoma: suggestion for an effective screening strategy for these tumors. J Thorac Oncol. 2011; 6(5):905-912.

(140.) Rodig SJ, Mino-Kenudson M, Dacic S, et al. Unique clinicopathologic features characterize ALK-rearranged lung adenocarcinoma in the western population. Clin Cancer Res. 2009; 15(16):5216-5223.

(141.) Shaw AT, Yeap BY, Mino-Kenudson M, et al. Clinical features and outcome of patients with non-small-cell lung cancer who harbor EML4-ALK. J Clin Oncol. 2009; 27(26):4247-4253.

(142.) Shaw AT, Yeap BY, Solomon BJ, et al. Effect of crizotinib on overall survival in patients with advanced non-small-cell lung cancer harbouring ALK gene rearrangement: a retrospective analysis. Lancet Oncol. 2011; 12(11):1004-1012.

(143.) Atherly AJ, Camidge DR. The cost-effectiveness of screening lung cancer patients for targeted drug sensitivity markers. Br J Cancer. 2012; 106(6):1100 1106.

(144.) Kwak EL, Bang YJ, Camidge DR, et al. Anaplastic lymphoma kinase inhibition in non-small-cell lung cancer. N Engl J Med. 2010; 363(18):1693 1703.

(145.) Ou SH, Bazhenova L, Camidge DR, et al. Rapid and dramatic radiographic and clinical response to an ALK inhibitor (crizotinib, PF02341066) in an ALK translocation-positive patient with non-small cell lung cancer. J Thorac Oncol. 2010; 5(12):2044-2046.

(146.) Bang YJ. The potential for crizotinib in non-small cell lung cancer: a perspective review. Ther Adv Med Oncol. 2011; 3(6):279-291.

(147.) Ou SH. Crizotinib: a novel and first-in-class multitargeted tyrosine kinase inhibitor for the treatment of anaplastic lymphoma kinase rearranged non-small cell lung cancer and beyond. Drug Des Devel Ther. 2011; 5:471-485.

(148.) Fallet V, Toper C, Antoine M, Cadranel J, Wislez M. Management of crizotinib, a new individualized treatment. Bull Cancer. 2012; 99(7-8):787-791.

(149.) Goozner M. Drug approvals 2011: Focus on companion diagnostics. J Natl Cancer Inst. 2012; 104(2):84-86.

(150.) Pennell NA. Treating ALK-positive lung cancer in the weeks after the FDA approval of crizotinib. Am J Manag Care. 2012; 18(5)(spec No. 2):SP84-SP87.

(151.) Shaw AT, Solomon B, Kenudson MM. Crizotinib and testing for ALK. J Natl Compr Canc Netw. 2011; 9(12):1335-1341.

(152.) Choi YL, Soda M, Yamashita Y, et al. EML4-ALK mutations in lung cancer that confer resistance to ALK inhibitors. N Engl J Med. 2010; 363(18):1734-1739.

(153.) Doebele RC, Pilling AB, Aisner DL, et al. Mechanisms of resistance to crizotinib in patients with ALK gene rearranged non-small cell lung cancer. Clin Cancer Res. 2012; 18(5):1472-1482.

(154.) KatayamaR, Khan TM, Benes C, et al. Therapeutic strategies to overcome crizotinib resistance in non-small cell lung cancers harboring the fusion oncogene EML4-ALK. Proc Natl Acad Sci USA. 2011; 108(18):7535-7540.

(155.) Katayama R, Shaw AT, Khan TM, et al. Mechanisms of acquired crizotinib resistancein ALK-rearranged lung cancers. Sci Transl Med. 2012; 4(120):120ra17.

(156.) Soria JC, Mok TS, Cappuzzo F, Janne PA. EGFR-mutated oncogeneaddicted non-small cell lung cancer: current trends and future prospects. Cancer Treat Rev. 2012; 38(5):416-430.

(157.) Navani N, Brown JM, Nankivell M, et al. Suitability of endobronchial ultrasound-guided transbronchial needle aspiration specimens for subtyping and genotypingofnon-small cell lungcancer: a multicenter study of 774 patients. Am J Respir Crit Care Med. 2012; 185(12):1316-1322.

(158.) Rekhtman N, Brandt SM, Sigel CS, et al. Suitability of thoracic cytology for new therapeutic paradigms in non-small cell lung carcinoma: high accuracy of tumor subtyping and feasibility of EGFR and KRAS molecular testing. J Thorac Oncol. 2011; 6(3):451-458.

(159.) Solomon SB, Zakowski MF, Pao W, et al. Core needle lung biopsy specimens: adequacy for EGFR and KRAS mutational analysis. AJR Am J Roentgenol. 2010; 194(1):266-269.

(160.) Hasanovic A, Ang D, Moreira AL, Zakowski MF. Use of mutation specific antibodies to detect EGFR status in small biopsy and cytology specimens of lung adenocarcinoma. Lung Cancer. 2012; 77(2):299-305.

(161.) Aisner DL, Deshpande C, Baloch Z, et al. Evaluation of EGFR mutation status in cytology specimens: an institutional experience. Diagn Cytopathol. 2011.

(162.) Bruno P, Mariotta S, Ricci A, et al. Reliability of direct sequencing of EGFR: comparison between cytological and histological samples from the same patient. Anticancer Res. 2011;31(12):4207-4210.

(163.) Gil-Bazo I, Castanon E, Fusco JP. EGFR mutation testing in non-small-cell lung cancer patients by using cytology specimens: when the tissue is no longer the issue. Cancer Cytopathol. 2011; 119(5):354.

(164.) Kanaji N, Bandoh S, Ishii T, et al. Detection of EML4-ALK fusion genes in a few cancer cells from transbronchial cytological specimens utilizing immediate cytology during bronchoscopy. Lung Cancer. 2012; 77(2):293-298.

(165.) Pang B, Matthias D, Ong CW, et al. The positive impact of cytological specimens for EGFR mutation testing in non-small cell lung cancer: a single South East Asian laboratory's analysis of 670 cases. Cytopathology. 2012; 23(4): 229-236.

(166.) Zhuang YP, Wang HY, Shi MQ, Zhang J, Feng Y. Use of CT-guided fine needle aspiration biopsy in epidermal growth factor receptor mutation analysis in patients with advanced lung cancer. Acta Radiol. 2011; 52(10):1083-1087.

(167.) Mino-Kenudson M, Mark EJ. Reflex testing for epidermal growth factor receptor mutation and anaplastic lymphoma kinase fluorescence in situ hybridization in non-small cell lung cancer. Arch Pathol Lab Med. 2011; 135(5):655-664.

(168.) Cheung HW, Du J, Boehm JS, et al. Amplification of CRKL induces transformation and epidermal growth factor receptor inhibitor resistance in human non-small cell lung cancers. Cancer Discov. 2011; 1(7):608-625.

(169.) Ercan D, Zejnullahu K, Yonesaka K, et al. Amplification of EGFR T790M causes resistance to an irreversible EGFR inhibitor. Oncogene. 2010; 29(16): 2346-2356.

(170.) Nguyen KS, Kobayashi S, Costa DB. Acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors in non-small-cell lung cancers dependent on the epidermal growth factor receptor pathway. Clin Lung Cancer. 2009; 10(4):281-289.

(171.) Zhang Z, Lee JC, Lin L, et al. Activation of the AXL kinase causes resistance to EGFR-targeted therapy in lung cancer. Nat Genet. 2012.

(172.) Brugger W, Thomas M. EGFR-TKI resistant non-small cell lung cancer (NSCLC): new developments and implications for future treatment. Lung Cancer. 2012; 77(1):2-8.

(173.) Hirsch FR, Bunn PA Jr. A new generation of EGFR tyrosine-kinase inhibitors in NSCLC. Lancet Oncol. 2012; 13(5):442-443.

(174.) Kim ES, Herbst RS, Wistuba II, et al. The BATTLE trial: personalizing therapy for lung cancer. Cancer Discov. 2011; 1(1):44-53.

(175.) Langer CJ, Mok T, Postmus PE. Targeted agents in the third-/fourth-line treatment of patients with advanced (stage III/IV) non-small cell lung cancer (NSCLC). Cancer Treat Rev. 2012.

(176.) Belani CP. The role of irreversible EGFR inhibitors in the treatment of non-small cell lung cancer: overcoming resistance to reversible EGFR inhibitors. Cancer Invest. 2010; 28(4):413-423.

(177.) Doebele RC, Oton AB, Peled N, Camidge DR, Bunn PA Jr. New strategies to overcome limitations of reversible EGFR tyrosine kinase inhibitor therapy in non-small cell lung cancer. Lung Cancer. 2010; 6 9(1):1-12.

(178.) Giaccone G, Wang Y. Strategies for over coming resistance to EGFR family tyrosine kinase inhibitors. Cancer Treat Rev. 2011; 37(6):456-464.

(179.) Kwak E. The role of irreversible HER family inhibition in the treatment of patients with non-small cell lung cancer. Oncologist. 2011; 16(11):1498-1507.

(180.) Kim Y, Ko J, Cui Z, et al. The EGFR T790M mutation in acquired resistance to an irreversible second-generation EGFR inhibitor. Mol Cancer Ther. 2012; 11(3):784-791.

(181.) Miller VA, Hirsh V, Cadranel J, et al. Afatinib versus placebo for patients with advanced, metastatic non-small-cell lung cancer after failure of erlotinib, gefitinib, or both, and one or two lines of chemotherapy (LUX-lung 1): a phase 2b/3 randomised trial. Lancet Oncol. 2012; 13(5):528-538.

(182.) Ou SH. Second-generation irreversible epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs): a better mousetrap?: a review of the clinical evidence. Crit Rev Oncol Hematol. 2012.

(183.) Ramalingam SS, Blackhall F, Krzakowski M, et al. Randomized phase II study of dacomitinib (PF-00299804), an irreversible pan-human epidermal growth factor receptor inhibitor, versus erlotinib in patients with advanced non-small-cell lung cancer. J Clin Oncol. 2012.

(184.) Yang JC, Shih JY, Su WC, et al. Afatinib for patients with lung adenocarcinoma and epidermal growth factor receptor mutations (LUX-lung 2): a phase 2 trial. Lancet Oncol. 2012; 13(5):539-548.

(185.) Hirsh V. Afatinib (BIBW 2992) development in non-small-cell lung cancer. Future Oncol. 2011; 7(7):817-825.

(186.) Metro G, Crino L. The LUX-lung clinical trial program of afatinib for non-small-cell lung cancer. Expert Rev Anticancer Ther. 2011; 11(5):673-682.

(187.) Murakami H, Tamura T, Takahashi T, et al. Phase I study of continuous afatinib (BIBW 2992) in patients with advanced non-small cell lung cancer after prior chemotherapy/erlotinib/gefitinib (LUX-lung 4). Cancer Chemother Pharmacol. 2012; 69(4):891-899.

(188.) Engelman JA, Zejnullahu K, Gale CM, et al. PF00299804, an irreversible pan-ERBB inhibitor, is effective in lung cancer models with EGFR and ERBB2 mutations that are resistant to gefitinib. Cancer Res. 2007; 67(24):11924-11932.

(189.) Kelly RJ, Carter C, Giaccone G. Personalizing therapy in an epidermal growth factor receptor-tyrosine kinase inhibitor-resistant non-small-cell lung cancer usingPF-00299804 and trastuzumab. J Clin Oncol. 2010; 28(28):e507-10.

(190.) Chmielecki J, Pietanza MC, Aftab D, et al. EGFR-mutant lung adenocarcinomas treated first-line with the novel EGFR inhibitor, XL647, can subsequently retain moderate sensitivity to erlotinib. J Thorac Oncol. 2012; 7(2): 434-442.

(191.) Pietanza MC, Gadgeel SM, Dowlati A, et al. Phase II study of the multitargeted tyrosine kinase inhibitor XL647 in patients with non-small-cell lung cancer. J Thorac Oncol. 2012; 7(5):856-865.

(192.) Pietanza MC, Lynch TJ Jr, Lara PN Jr, et al. XL647--a multi-targeted tyrosine kinase inhibitor: results of a phase II study in subjects with non-small cell lung cancer who have progressed after responding to treatment with either gefitinib or erlotinib. J Thorac Oncol. 2012; 7(1):219-226.

(193.) Arcila ME, Oxnard GR, Nafa K, et al. Rebiopsy of lung cancer patients with acquired resistance to EGFR inhibitors and enhanced detection of the T790M mutation using a locked nucleic acid-based assay. Clin CancerRes. 2011; 17(5):1169-1180.

(194.) Oxnard GR, Arcila ME, Sima CS, et al. Acquired resistance to EGFR tyrosine kinase inhibitors in EGFR-mutant lung cancer: distinct natural history of patients with tumors harboring the T790M mutation. Clin Cancer Res. 2011; 17(6):1616-1622.

(195.) Carillio G, Montanino A, Costanzo R, et al. Cetuximab in non-small-cell lung cancer. Expert Rev Anticancer Ther. 2012; 12(2):163-175.

(196.) Pirker R, Pereira JR, Szczesna A, et al. Prognostic factors in patients with advanced non-small cell lung cancer: data from the phase III FLEX study. Lung Cancer. 2012; 77(2):376-382.

(197.) Pirker R, Pereira JR, von Pawel J, et al. EGFR expression as a predictor of survival for first-line chemotherapy plus cetuximab in patients with advanced non-small-cell lung cancer: analysis of data from the phase 3 FLEX study. Lancet Oncol. 2012; 13(1):33-42.

(198.) O'Byrne KJ, Gatzemeier U, Bondarenko I, et al. Molecular biomarkers in non-small-cell lung cancer: a retrospective analysis of data from thephase3 FLEX study. Lancet Oncol. 2011; 12(8):795-805.

(199.) Herbst RS, Kelly K, Chansky K, et al. Phase II selection design trial of concurrent chemotherapy and cetuximab versus chemotherapy followed by cetuximab in advanced-stage non-small-cell lung cancer: Southwest Oncology Group study S0342. J Clin Oncol. 2010;28(31):4747-4754.

(200.) Redman MW, Crowley JJ, Herbst RS, Hirsch FR, Gandara DR. Design of a phase III clinical trial with prospective biomarker validation: SWOG S0819 [published online ahead of print May 16, 2012]. Clin Cancer Res. 2012; 18(15): 4004-4012.

(201.) Takeuchi K, Soda M, Togashi Y, et al. RET, ROS1 and ALK fusions in lung cancer. Nat Med. 2012; 18(3):378-381.

(202.) Yasuda H, de Figueiredo-Pontes LL, Kobayashi S, Costa DB. Preclinical rationale for use of the clinically available multi targeted tyrosine kinase inhibitor crizotinib in ROS1-translocated lung cancer. J Thorac Oncol. 2012; 7(7):1086 1090.

(203.) Forde PM, Rudin CM. Crizotinib in the treatment of non-small-cell lung cancer. Expert Opin Pharmacother. 2012; 13(8):1195-1201.

(204.) Bergethon K, Shaw AT, Ou SH, et al. ROS1 rearrangements define a unique molecular class of lung cancers. J Clin Oncol. 2012; 30(8):863-870.

(205.) Janne PA, Meyerson M. ROS1 rearrangements in lung cancer: a new genomic subset of lung adenocarcinoma. J Clin Oncol. 2012; 30(8):878-879.

(206.) Ou SH, Tan J, Yen Y, Soo RA. ROS1 as a 'druggable' receptor tyrosine kinase: lessons learned from inhibiting the ALK pathway. Expert Rev Anticancer Ther. 2012; 12(4):447-456.

(207.) Rimkunas VM, Crosby K, Kelly M, et al. Analysis of receptor tyrosine kinase ROS1 positive tumors in non-small cell lung cancer: Identification of a FIG-ROS1 fusion [published onlineahead of print June 1, 2012]. Clin Cancer Res. 2012; 18(16):4449-4457.

(208.) Yokota K, Sasaki H, Okuda K, et al. KIF5B/RET fusion gene in surgically treated adenocarcinoma of the lung [published online ahead of print July 13, 2012]. Oncol Rep. doi:10.3892/or.2012.

(209.) Lipson D, Capelletti M, Yelensky R, et al. Identification of new ALK and RET genefusionsfrom colorectal and lung cancer biopsies. NatMed. 2012; 18(3): 382-384.

(210.) Li F, Feng Y, Fang R, et al. Identification of RET gene fusion by exon array analyses in "pan-negative" lung cancer from never smokers. CellRes. 2012; 22(5): 928-931.

(211.) Kohno T, Ichikawa H, Totoki Y, et al. KIF5B-RET fusions in lung adenocarcinoma. Nat Med. 2012; 18(3):375-377.

(212.) Ju YS, Lee WC, Shin JY, et al. AtransformingKIF5B and RET genefusion in lung adenocarcinoma revealed from whole-genome and transcriptome sequencing. Genome Res. 2012; 22(3):436-445.

(213.) Sierra JR, Tsao MS. c-METas a potential therapeutic target and biomarker in cancer. Ther Adv MedOncol. 2011; 3(1 suppl):S21-S35.

(214.) Scagliotti GV, Novello S, Schiller JH, et al. Rationale and design of MARQUEE: A phase III, randomized, double-blind study of tivantinib plus erlotinib versus placebo plus erlotinib in previously treated patients with locally advanced or metastatic, nonsquamous, non-small-cell lung cancer [published online ahead of print March 21, 2012]. Clin Lung Cancer. 2012; 13:391-395.

(215.) Sequist LV, von Pawel J, Garmey EG, et al. Randomized phase II study of erlotinib plus tivantinib versus erlotinib plus placebo in previously treated non small-cell lung cancer. J Clin Oncol. 2011;29(24):3307-3315.

(216.) Gridelli C, Maione P, Rossi A. The potential role of mTOR inhibitors in non-small cell lung cancer. Oncologist. 2008; 13(2):139-147.

(217.) Herrera VA, Zeindl-Eberhart E, Jung A, Huber RM, Bergner A. The dual PI3K/mTOR inhibitor BEZ235 is effective in lung cancer cell lines. Anticancer Res. 2011; 31(3):849-854.

(218.) Kim YS, Jin HO, Seo SK, et al. Sorafenib induces apoptotic cell death in human non-small cell lung cancer cells by down-regulating mammalian target of rapamycin (mTOR)-dependent survivin expression. Biochem Pharmacol. 2011; 82(3):216-226.

(219.) Papadimitrakopoulou V. Development of PI3K/AKT/mTOR pathway inhibitors and their application in personalized therapy for non-small-cell lung cancer. J Thorac Oncol. 2012.

(220.) Ramalingam SS, Harvey RD, Saba N, et al. Phase 1 and pharmacokinetic study of everolimus, a mammalian target of rapamycin inhibitor, in combination with docetaxel for recurrent/refractory nonsmall cell lung cancer. Cancer. 2010; 116(16):3903-3909.

(221.) Reungwetwattana T, Molina JR, Mandrekar SJ, et al. Briefreport: Aphase II "window-of-opportunity" frontline study of the mTOR inhibitor, temsirolimus given as a single agent in patients with advanced NSCLC, an NCCTG study. J Thorac Oncol. 2012; 7(5):919-922.

(222.) Soria JC, Shepherd FA, Douillard JY, et al. Efficacy of everolimus (RAD001) in patients with advanced NSCLC previously treated with chemotherapy alone or with chemotherapy and EGFR inhibitors. Ann Oncol. 2009; 20(10): 1674-1681.

(223.) Vansteenkiste J, Solomon B, Boyer M, et al. Everolimus in combination with pemetrexed in patientswith advanced non-small cell lungcancer previously treated with chemotherapy: a phase I study using a novel, adaptive Bayesian dose-escalation model. J Thorac Oncol. 2011; 6(12):2120-2129.

(224.) Wu C, Wangpaichitr M, Feun L, et al. Overcoming cisplatin resistance by mTOR inhibitor in lung cancer. Mol Cancer. 2005; 4(1):25.

(225.) Xu CX, Li Y, Yue P, et al. The combination of RAD001 and NVP-BEZ235

exerts synergistic anticancer activity against non-small cell lung cancer in vitro and in vivo. PLoS One. 2011; 6(6):e20899.

(226.) Zito CR, Jilaveanu LB, Anagnostou V, et al. Multi-level targeting of the phosphatidylinositol-3-kinase pathway in non-small cell lung cancer cells. PLoS One. 2012; 7(2):e31331.

(227.) Zou ZQ, Zhang LN, Wang F, Bellenger J, Shen YZ, Zhang XH. The novel dual PI3K/mTOR inhibitor GDC-0941 synergizes with the MEK inhibitor U0126 in non-small cell lung cancer cells. Mol Med Report. 2012; 5(2):503-508.

(228.) Daniels GA, Adjei AA. Advances in systemic therapy of small cell cancer of the lung. Expert Rev Anticancer Ther. 2001; 1(2):211-221.

(229.) Pandya KJ, Dahlberg S, Hidalgo M, et al. A randomized, phase II trial of two dose levels of temsirolimus (CCI-779) in patients with extensive-stage small cell lung cancer who have responding or stable disease after induction chemotherapy: a trial of the Eastern Cooperative Oncology Group (E1500). J Thorac Oncol. 2007; 2(11):1036-1041.

(230.) Schmid K, Bago-Horvath Z, Berger W, et al. Dual inhibition of EGFR and mTOR pathways in small cell lung cancer. Br J Cancer. 2010; 103(5):622-628.

(231.) Sher T, Dy GK, Adjei AA. Small cell lung cancer. Mayo Clin Proc. 2008; 83(3):355-367.

(232.) Tarhini A, Kotsakis A, Gooding W, et al. Phase II study of everolimus (RAD001) in previously treated small cell lung cancer. Clin Cancer Res. 2010; 16(23):5900-5907.

(233.) Achcar Rde O, Cagle PT, Jagirdar J. Expression of activated and latent signal transducer and activator of transcription 3 in 303 non-small cell lung carcinomasand 44malignantmesotheliomas: possible role for chemotherapeutic intervention. Arch Pathol Lab Med. 2007; 131(9):1350-1360.

(234.) Liu X, Guo W, Wu S, et al. Antitumor activity ofa novel STAT3 inhibitor and redox modulator in non-small cell lung cancer cells. Biochem Pharmacol. 2012; 83(10):1456-1464.

(235.) Shimokawa T, Seike M, Soeno C, et al. Enzastaurin has anti-tumour effects in lung cancers with overexpressed JAK pathway molecules. Br J Cancer.

2012; 106(5):867-875.

(236.) Zhang X, Yue P, Page BD, et al. Orally bioavailable small-molecule inhibitor of transcription factor Stat3 regresses human breast and lung cancer xenografts. Proc Natl Acad Sci U S A. 2012; 109(24):9623-9628.

(237.) Kruser TJ, Traynor AM, Wheeler DL. The use of single-agent dasatinib in molecularly unselected non-small-cell lungcancer patients. Expert Opin Investig Drugs. 2011; 20(2):305-307.

(238.) Johnson ML, Riely GJ, Rizvi NA, et al. Phase II trial of dasatinib for patients with acquired resistance to treatment with the epidermal growth factor receptor tyrosine kinase inhibitors erlotinib or gefitinib. J Thorac Oncol. 2011; 6(6):1128-1131.

(239.) Johnson FM, Bekele BN, Feng L, et al. Phase II study of dasatinib in patients with advanced non-small-cell lung cancer. J Clin Oncol. 2010;28(30): 4609-4615.

(240.) Adjei AA. K-ras as a target for lung cancer therapy. J Thorac Oncol. 2008; 3(6)(suppl 2):S160-S163.

(241.) Tanizaki J, Okamoto I, Takezawa K, et al. Combined effect of ALK and MEK inhibitors in EML4-ALK-positive non-small-cell lung cancer cells. Br J Cancer. 2012; 106(4):763-767.

(242.) Dy G. MEK/MAPK inhibitors. J Thorac Oncol. 2010; 5(12)(suppl 6):S474S475.

(243.) Haura EB, Ricart AD, Larson TG, et al. Aphase II study of PD-0325901, an oral MEK inhibitor, in previouslytreated patientswith advanced non-small cell lung cancer. Clin Cancer Res. 2010; 16(8):2450-2457.

(244.) Furney SJ, Gundem G, Lopez-Bigas N. Oncogenomics methods and resources. Cold Spring Harb Protoc. 2012; 2012(5). doi:10.1101/pdb.top069229.

(245.) Jia P, Zhao Z. Personalized pathway enrichment map of putative cancer genes from next generation sequencing data. PLoS One. 2012; 7(5):e37595.

(246.) Kalari KR, Rossell D, Necela BM, et al. Deep sequence analysis of nonsmall cell lung cancer: integrated analysis of gene expression, alternative splicing, and single nucleotide variations in lung adenocarcinomas with and without oncogenic KRAS mutations. Front Oncol. 2012; 2:12.

(247.) Marchetti A, Del Grammastro M, Filice G, et al. Complex mutations & subpopulations of deletions at exon 19 of EGFR in NSCLC revealed by next generation sequencing: potential clinical implications. PLoS One. 2012; 7(7): e42164.

(248.) Oxnard GR, Miller VA, Robson ME, et al. Screening for germline EGFR T790M mutations through lung cancer genotyping. J Thorac Oncol. 2012; 7(6): 1049-1052.

(249.) Yauch RL, Settleman J. Recent advances in pathway-targeted cancer drug therapies emerging from cancer genome analysis. Curr Opin Genet Dev. 2012; 22(1):45-49.

(250.) Boland JM, Erdogan S, Vasmatzis G, et al. Anaplastic lymphoma kinase immunoreactivity correlates with ALK gene rearrangement and transcriptional up-regulation in non-small cell lung carcinomas. Hum Pathol. 2009; 40(8):1152 1158.

(251.) Mino-Kenudson M, Chirieac LR, Law K, et al. A novel, highly sensitive antibody allows for the routine detection of ALK-rearranged lung adenocarcinomas by standard immunohistochemistry. Clin Cancer Res. 2010; 16(5):1561 1571.

(252.) Yi ES, Boland JM, Maleszewski JJ, et al. Correlation of IHC and FISH for ALK gene rearrangement in non-small cell lung carcinoma: IHC score algorithm for FISH. J Thorac Oncol. 2011; 6(3):459-465.

(253.) Brevet M, Arcila M, Ladanyi M. Assessment of EGFR mutation status in lung adenocarcinoma by immunohistochemistry using antibodies specific to the two major forms of mutant EGFR. J Mol Diagn. 2010; 12(2):169-176.

(254.) Yu J, Kane S, Wu J, et al. Mutation-specific antibodies for the detection of EGFR mutations in non-small-cell lung cancer. Clin Cancer Res. 2009; 15(9): 3023-3028.

Philip T. Cagle, MD; Timothy Craig Allen, MD, JD

* References 3, 4, 8, 17, 18, 36, 37, 40, 43, 44.

([dagger]) References 35, 36, 40, 43, 45, 46, 69, 92, 93.

([double dagger]) References 35, 36, 40, 41, 43, 60, 69, 93.

[section] References 3, 4, 34-37, 39, 40, 42, 45, 69, 99.

([parallel]) References 3, 4, 35-37, 39-40, 42, 43, 69, 125-127.

([paragraph]) References 3, 4, 35-37, 39-40, 42, 43, 69, 93.

(#) References 3, 4, 34-37, 39, 40, 42, 45, 69, 99, 156.

** References 3, 4, 8, 34-37, 39, 40, 42, 45, 69.

([dagger])([dagger]) References 89, 91, 102-104, 152-155, 168-171.

Accepted for publication August 16, 2012.

From the Department of Pathology & Genomic Medicine, The Methodist Hospital, Houston, Texas (Dr Cagle); and the Department of Pathology, University of Texas Health Science Center at Tyler (Dr Allen).

The authors have no relevant financial interest in the products or companies described in this article.

Reprints: Philip T. Cagle, MD, Department of Pathology & Genomic Medicine, The Methodist Hospital, 6565 Fannin St, Main Bldg, Room 227, Houston, TX 77030 (e-mail:
COPYRIGHT 2012 College of American Pathologists
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2012 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Cagle, Philip T.; Allen, Timothy Craig
Publication:Archives of Pathology & Laboratory Medicine
Date:Dec 1, 2012
Previous Article:A unique, histopathologic lesion in a subset of patients with spontaneous pneumothorax.
Next Article:Evolving frontlines in the diagnosis and treatment of pulmonary diseases.

Terms of use | Privacy policy | Copyright © 2022 Farlex, Inc. | Feedback | For webmasters |