Printer Friendly

Sentinel lymph node biopsy in SCC of the head and neck: A major advance in staging the NO neck.

Abstract

The management of the NO neck in patients with head and neck cancer is controversial. Neck dissection provides important staging information that guides patient treatment. We examined the feasibility of using a dye technique for staging patients by sentinel lymph node biopsy (SLNBX). We studied seven patients with previously untreated early-stage squamous cell carcinoma of the oral cavity and NO necks. Each patient underwent SLNBX guided by an intraoperative injection of 1% isosulfan blue dye. An open biopsy of the sentinel node was followed by neck dissection. We identified the sentinel node in four of the seven patients (57%). The sentinel node accurately predicted the pathologic status of the neck in three of these four patients (75%). In one of the three patients, the sentinel node was one of four histopathologically positive nodes, whereas in two others, the neck was free of disease. One patient had a histopathologically negative sentinel node and tumor metastasis present in the neck. Of the four patient s in whom a sentinel node was identified, the negative predictive value for the absence of cervical metastases was 67%. Based on our findings and those of other authors, we conclude that the use of blue dye in lymphatic mapping for SLNBX in head and neck cancer patients is technically feasible but of limited clinical utility. Our literature review also suggests that performing SLNBX with a radiotracer technique or a combination of a radiotracer and blue dye is a promising method of staging the NO neck in head and neck cancer patients and warrants further clinical study.

Introduction

Sentinel lymph node biopsy (SLNBX) has become an accepted technique for determining whether metastases are present in the first extratumoral echelon of draining lymph nodes in melanoma and breast cancer patients. SLNBX has allowed these patients to avoid procedural morbidity while undergoing staging for their malignancies. If this technique could be shown to be applicable to head and neck cancer, it would represent a major advancement in staging these patients.

The objective of this study was to evaluate the feasibility of SLNBX by using an isosulfan blue dye lymphatic mapping technique in patients with squamous cell carcinoma of the oral cavity. A secondary objective was to review the results of this study within the context of the current literature.

Patients and methods

The eligibility criteria for participation in this prospective study were a diagnosis of previously untreated, biopsyproven squamous cell carcinoma of the oral cavity and no clinical evidence of neck disease. Patients who had a history of a dye reaction or severe asthma were excluded from the study. From December 2000 through July 2001, we enrolled seven consecutive patients--three men and four women, aged 41 to 77 years (mean: 65). The primary tumor was located in the oral tongue in five patients, in the floor of the mouth in one patient, and in the alveolar ridge in one patient (table 1).

Lymphatic mapping was carried out after each patient was placed under general anesthesia. We injected 1.5 ml of 1% isosulfan blue dye into the submucosa beneath and circumferentially around the primary tumor. A supraomohyoid neck dissection was then performed on the side ipsilateral to the tumor. A subplatysmal skin flap was first raised, and all lymphatic tissue was closely examined for blue staining. Any lymph node that stained blue was considered to be a sentinel node (figure). The sentinel node or nodes were then dissected free from the main specimen and sent separately for permanent histologic evaluation. The neck dissection was completed in the usual fashion, and the contents were sent for histopathologic evaluation. After the neck dissection was completed, the primary oral tumor was resected. Intraoperative negative frozen-section margins were obtained in all patients.

Results

The sentinel node was identified in four of the seven patients (57%), and it accurately predicted the pathologic status of the neck in three of the four (75%). The negative predictive value for the absence of cervical metastases in the four patients was 67%. We also evaluated data with respect to the primary tumor location, sentinel node location, and pathologic findings (table 2). One patient (patient 4) had a histopathologically negative sentinel node, but disease was present in her neck dissection specimen. In one patient (patient 2), the sentinel node was one of four histopathologically positive nodes, whereas in two others (patients 1 and 3), the neck was free of disease. Sentinel nodes were not identified in three patients--one whose tumor was in the tongue (patient 5), the patient whose tumor involved the floor of the mouth (patient 6), and the patient whose tumor involved the alveolar ridge (patient 7). None of these three patients had metastatic disease in the neck dissection specimen.

The localization of sentinel nodes with isosulfan blue dye required additional operative time. It took approximately 15 extra minutes to inject the dye, localize the node, and dissect it free. Reported complications of dye injection, which include infection and allergic reaction, (1) were not observed in our study.

Discussion

In patients who have head and neck squamous cell carcinoma (HNSCC), the presence of nodal disease--either gross or microscopic--remains the most important factor in predicting disease recurrence and survival. [2-5] The presence of nodal metastases can shorten 5-year survival by as much as 5O%. [2] Depending on the size and site of the primary tumor, anywhere from 7 to 89% of patients will have no clinical evidence of neck disease. [6-8] Between 20 and 40% of these NO patients will harbor microscopic foci of tumor. [8-10] If the probability of occult cervical metastasis is greater than 20%, treatment of the neck is warranted. (11)

Obtaining computed tomography or magnetic resonance imaging of the neck does not significantly improve the detection of occult disease. (12) Pathologic evaluation of the neck dissection specimen is considered to be the gold standard for neck node evaluation. Approximately two-thirds of early-stage NO patients who undergo neck dissection (and incur its associated morbidity) have no pathologic evidence of disease. (6,8) Potential complications of neck dissection include scarring, paresthesia, seroma, infection, pain, limitation of shoulder range of motion, deformity, and death. Failure to perform a dissection in favor of taking a wait-and-see approach in these patients can lead to disease recurrence and worsen the prognosis. (8)

The ideal neck-staging technique would allow for an accurate evaluation of nodal status while avoiding over-or undertreatment of the neck. SLNBX potentially allows for the accurate staging of patients with HNSCC and NO necks while avoiding neck dissection.

Despite controversy regarding its specific definition, (13) Morton et al's definition of a sentinel node as "the initial lymph node upon which the primary tumor drains" (14) is perhaps the most universally applicable. Lymphatic metastases do not occur randomly but predictably, in accordance with the pre-existing lymphatic anatomy. The sentinel node represents the first extratumoral echelon of nodes to receive metastases. The practice of staging or selective neck dissection--carried out by removing nodal levels that have the highest probability of harboring metastatic disease--is based on the results of studies that examined the patterns and frequency of neck nodal metastases in large patient populations. (6,7,15) Unlike selective neck dissection, sentinel node biopsy has the advantage of allowing for the direct evaluation of the first lymphatic drainage basin of a specific patient's tumor.

The first description of contemporary SLNBX techniques being carried out on an HNSCC patient was reported in 1996 by Alex and Krag. (16) The SLNBX was performed on an NO patient just prior to surgical treatment of a supraglottic laryngeal cancer. Intraoperatively, technetium-99m (Tc-99m) sulfur colloid was injected around the tumor, and gamma-probe guidance was used to identify the sentinel node, which correctly predicted the presence of neck nodal disease in this patient. Prior to this report, lymphoscintigraphy was found to be of limited diagnostic benefit in patients with head and neck cancer. (17-23)

Three methodologies have been used to perform SLMBX in patients with HNSCC (table 3). (24-36) These techniques are broadly classified as involving (1) the use of a radiotracer, (2) the use of a vital dye, and (3) the use of both together. The radiotracer technique, with lymphoscintigraphy and intraoperative gamma-probe-assisted localization, has been used by a number of investigators. (26-32) Koch et al performed SLNBX on five N0 patients who had squamous cell carcinoma of the oral cavity and oropharynx. (26) They injected Tc-99m sulfur colloid intramucosally around the primary tumor. The sentinel node was identified in two of these five patients (40%), and it accurately predicted the disease status of the neck in both. Sentinel nodes were not identified in the other three patients despite the presence of microscopic metastatic disease in two of them. Koch et al offered two possible explanations for their poor sentinel lymph node identification rate. One of their patients had a history of radiation treatment, which, they wrote, can "alter the known lymphatic channels rendering lymphoscintigraphy ineffective." A second patient in this study was described as having a "thick neck"--a neck in which gross nodal metastases were not clinically detectable--and this was another reason the authors believed that the accuracy of SLNBX was limited.

In six subsequent studies, the radiotracer technique with preoperative lymphoscintigraphy and intraoperative gamma-probe guidance was performed on 44 patients with N0 HNSCC, (27-32) Primary tumor sites included the oral cavity, oropharynx, hypopharynx, and larynx. Sentinel lymph nodes were identified in all 44 patients, and in each case they correctly predicted the lymph node status of the neck. In one of these studies, Chiesa et al used the radiotracer technique to perform SLNBX on 11 patients who had clinically NO necks. (29) First they resected the primary tumor in all patients. One month later, they performed SLNBX by injecting the area around the scar that resulted from the primary tumor resection. Sentinel nodes were identified in all patients. Of the eight patients who eventually underwent neck dissection, lymphoscintigraphy was performed on five prior to the primary resection. Chiesa et al then compared these lymphoscintigraphic findings with those that had been obtained during the SLNBX. This compar ison demonstrated that the pattern of lymphatic drainage from the primary tumor site had been altered by its resection. Regardless of this, in all eight patients who underwent neck dissection in this series, the sentinel nodes accurately predicted the pathologic status of the neck.

Colnot et al employed a radiotracer technique along with ultrasound-guided fine-needle aspiration biopsy to identify sentinel lymph nodes in a total of 12 HNSCC patients. (31) Sentinel nodes were identified in all six of the patients who underwent neck dissection, and all of these nodes accurately predicted the pathologic status of the neck. Furthermore, the fine-needle aspiration biopsy specimens also correctly predicted the pathologic status of the neck, although its use was limited by its inability to aspirate small (<2 mm) sentinel nodes.

In addition to our series of seven patients, two other series have described the use of vital dye alone for the identification of sentinel nodes in HNSCC. Pitman et al performed SLNBX on 16 HNSCC patients who had primary tumors in the oral cavity, oropharynx, hypopharynx, and larynx. (24) Nine of these patients had NO necks. However, the results of this study were disappointing in that no sentinel lymph node had been identified in any patient. Shoaib et al also reported disappointing results after using vital dye alone. (25) They performed SLNBX on 25 HNSCC patients who had primary tumors of the oral cavity or oropharynx. Of these 25 patients, 13 underwent SLNBX with Patent Blue V dye alone. Of these 13 patients, seven were N+ and six were NO. The six NO patients underwent neck dissection. Sentinel lymph nodes were identified in four of the six (67%), and they correctly predicted the pathologic status of the neck in only two of the four (50%). In the remaining 12 patients, Shoaib et al also carried out SLNBX with a combination dye and radiotracer technique. Ten of these patients were included in a subsequent report by Shoaib et al (described later in this article). (34)

The combined use of radiocolloid and dye for SLNBX in HNSCC has been described in three reports. (33-35) Bilchik et al used radiotracer and isosulfan blue dye on five patients who had primary tumors of the oral cavity, and they identified a sentinel node in all five. (33) However, neck dissection was carried out only in the one patient who had a positive sentinel node. It is unclear from this study whether the sentinel node was identified by the dye, by the radiocolloid, or by a combination of both.

Shoaib et al performed SLNBX on 39 NO patients and one NX patient with squamous cell carcinoma of the oral cavity or oropharynx. (34) (This series included the nine NO patients and one NX patient who had been described in their previous report. (25)) They combined preoperative lymphoscintigraphy with intraoperative gamma-probe guidance and Patent Blue V dye. The radiocolloid they used was Tc-99m-labeled colloidal human serum albumin. The sentinel node was identified in 36 of 40 patients (90%), and it correctly predicted the nodal status of the neck in 35 of the 36 (97%). The one patient who had a false-negative lymph node (the sentinel node was identified and found to be free of tumor, but tumor was present in the neck dissection specimen) was found to have an extensive T4 tumor of the floor of the mouth. Shoaib et al attributed this false negative to the extent of the lesion and to their inability to fully encompass the tumor during radiotracer and dye injection. In this series, the radiocolloid and the blu e dye techniques complemented one another. Of the total of 41 sentinel nodes that were found, 15 (37%) were identified by the radiotracer alone, five (12%) were identified by the dye alone, and 21 (51%) were simultaneously identified by the radiotracer and dye. Thus, in this study, the combination was more accurate than either technique alone.

Finally, Mozzillo et al carried out SLNBX on 41 NO patients who had squamous cell carcinoma of the oral cavity. (35) They too used preoperative lymphoscintigraphy, intraoperative gamma-probe guidance, and Patent Blue V dye. The sentinel node was identified in 39 of the 41 patients (95%). It is interesting that seven of the 39 patients (18%) had sentinel lymph nodes located at neck levels 4 or 5.

In conclusion, SLNBX carried out on clinically NO patients who have HNSCC represents a potential advance over selective dissection as an accurate method of neck staging. The SLNBX technique will reduce cost, time, and morbidity by decreasing the number of dissections that are performed on NO necks. Another potential benefit of SLNBX is that it can identify the small number of patients who harbor metastatic disease outside the levels that are removed by selective dissection. Although the numbers of patients in our series and in others are small and the clinical experience with this technique is limited, the efficacy of SLNBX for staging HNSCC appears to be comparable to that for staging other cancers.

Even so, before SLNBX becomes an accepted staging procedure, several issues must be addressed. These issues include a determination of which head and neck subsites and tumor stages are most appropriate for this technique. Moreover, the optimal method of performing this procedure remains to be defined. Finally, judging from the results of all the case series reviewed here, the use of a blue dye technique alone for SLNBX in HNSCC patients, while technically feasible, is of limited clinical utility, although it might emerge as an important adjunct to the radiotracer technique. If these issues can be resolved, it appears to us that the use of SLNBX for staging HNSCC is promising and warrants further study in future clinical trials.
Table 1.

Patient demographics


 Age (yr)/ Primary Tumor
Pt. sex location stage (37)
 1 70/F Oral tongue T2
 2 66/M Oral tongue T2
 3 77/F Oral tongue T2
 4 41/F Oral tongue T2
 5 58/M Oral tongue T1
 6 71/F Floor of the mouth T2
 7 69/M Alveolar ridge T2
Table 2.

Sentinel lymph node (SLN) biopsy results

 Sentinel node No. of Neck level Pathologic No. positive/
Pt. identified SLNs of SLN status of SLN total no. nodes

1 Yes 1 1 - 0/18
2 Yes 1 3 + 4/25
3 Yes 2 2 - 0/12
4 Yes 1 2 - 3/14

5 No N/A N/A N/A 0/23
6 No N/A N/A N/A 0/18
7 No N/A N/A N/A 0/35

 Level of
Pt. positive nodes

1 N/A
2 Level 3 (n = 4)
3 N/A
4 Level 1 (n= 1);
 level 2 (n = 2)
5 N/A
6 N/A
7 N/A
Table 3.

Comparison of sentinel lymph node (SLN) biopsy (BX) techniques in N0
patients with squamous cell carcinoma of the head and neck who underwent
neck dissection

 No. Location of SLNBX
Author pts. primary tumor (*) technique

Pitman et al, 1998 (24) 9 OC, OP, HP, LY Dye
Shoaib et al, 1999 (25) 6 OC, OP Dye
Wiseman et al, 2002 (+) 7 OC Dye
Koch et al, 1998 (26) 5 OC, OP Radiotracer
Werner et al, 1999 (27) 5 OP, HP, LY Radiotracer
Alex et al, 2000 (28) 8 OC, OP, LY Radiotracer
Chiesa et al, 2000 (29) 8 OC Radiotracer
Zitsch et al, 2000 (30) 8 OC, OP Radiotracer
Colnot et al, 2001 (31) 6 OC, OP Radiotracer
Taylor et al, 2001 (32) 9 OC, OP Radiotracer
Bilchik et al, 1998 (23) 1 OC Both
Shoaib et al, 2001 (34) 40 (ss) OC, OP Both
Mozzillo et al, 2001 (35) 41 OC Both

 SLN identified Identified SLN predicted
Author (% pts) neck pathology (% pts)

Pitman et al, 1998 (24) 0 0
Shoaib et al, 1999 (25) 67 50
Wiseman et al, 2002 (+) 57 75
Koch et al, 1998 (26) 40 100
Werner et al, 1999 (27) 100 100
Alex et al, 2000 (28) 100 100
Chiesa et al, 2000 (29) 100 100
Zitsch et al, 2000 (30) 100 100
Colnot et al, 2001 (31) 100 100
Taylor et al, 2001 (32) 100 100
Bilchik et al, 1998 (23) 100 Unknown
Shoaib et al, 2001 (34) 90 97
Mozzillo et al, 2001 (35) 95 100

(*)OC = oral cavity

OP = oropharynx

HP = hypopharynx

LY = larynx

(+)Present study.

(ss)Includes one patient who was staged NX because of lymphadenopathy
from long-standing non-Hodgkin's lymphoma.


References

(1.) Cimmino VM, Brown AC, Szocik JF, et al. Allergic reactions to isosulfan blue during sentinel node biopsy--a common event. Surgery 2001;130:439-42.

(2.) Grandi C, Alloisio M, Moglia D, et al. Prognostic significance of lymphatic spread in head and neck carcinomas: Therapeutic implications. Head Neck Surg 1985;8:67-73.

(3.) Kalnins 1K, Leonard AG, Sako K, et al. Correlation between prognosis and degree of lymph node involvement in carcinoma of the oral cavity. Am J Surg 1977:134:450-4.

(4.) Schuller DE, McGuirt WF, McCabe BF, Young D. The prognostic significance of metastatic cervical lymph nodes. Laryngoscope 1980;90:557-70.

(5.) Snow GB, Annyas AA, van Slooten EA, et al. Prognostic factors of neck node metastasis. Clin Otolaryngol 1982;7:185-92.

(6.) Lindberg R. Distribution of cervical lymph node metastases from squamous cell carcinoma of the upper respiratory and digestive tracts. Cancer 1972;29:1446-9.

(7.) Li XM, Wei WI, Guo XF, et al. Cervical lymph node metastatic patterns of squamous carcinomas in the upper aerodigestive tract. J Laryngol Otol 1996;110:937-41.

(8.) Jones AS, Phillips DE, Helliwell TR, Roland NJ. Occult node metastases in head and neck squamous carcinoma. Eur Arch Otorhinolaryngol 1993;250:446-9.

(9.) Shah JP, Andersen PE. Evolving role of modifications in neck dissection for oral squamous carcinoma. Br J Oral Maxillofac Surg 1995;33:3-8.

(10.) Shah JP. Patterns of cervical lymph node metastasis from squamous carcinomas of the upper aerodigestive tract. Am J Surg 1990;160:405-9.

(11.) Weiss MH, Harrison LB, lsaacs RS. Use of decision analysis in planning a management strategy for the stage NO neck. Arch Otolaryngol Head Neck Surg 1994;120:699-702.

(12.) Don DM, Anzai Y, Lufkin RB, et al. Evaluation of cervical lymph node metastases in squamous cell carcinoma of the head and neck, Laryngoscope 1995;105:669-74.

(13.) Nieweg OE, Tanis PJ, Kroon BB. The definition of a sentinel node. Ann Surg Oncol 2001;8:538-41.

(14.) Morton DL, Wen DR, Wong JH, et al. Technical details of intraoperative lymphatic mapping for early stage melanoma. Arch Surg 1992;127:392-9.

(15.) Mamelle G. Selective neck dissection and sentinel node biopsy in head and neck squamous cell carcinomas. Recent Results Cancer Res 2000;157:193-200.

(16.) Alex JC, Krag DN. The gamma-probe-guided resection of radiolabeled primary lymph nodes. Surg Oncol Clin North Am 1996;5:33-41.

(17.) Larson DL, Lewis SR, Rapperport AS, et al. Lymphatics of the mouth and neck. Am J Surg 1965;110:625-30.

(18.) Sri-Pathmanathan R, Railton R. Lymphoscintigraphy in the detection of cervical metastases from oral carcinoma: A pilot study. Ann R Coll Surg Engl 1989;71:281-4.

(19.) Terui S, Terauchi T, Ebihara S, et al. Lymphoscintigraphy of head-and-neck cancer. Angiology 1992;43:925-32.

(20.) Charron M, Mochizuki T, Levine G, Tauxe WN. Lymphoscintigraphy in the detection of cervical metastases from oral carcinoma: A pilot study [comment]. Ann R Coll Surg Engl 199l;73:332.

(21.) Matoba N, Kikuchi T. Thyroidolymphography. A new technic for visualization of the thyroid and cervical lymph nodes. Radiology 1969;92:339-42.

(22.) Wallace S, Laird J, Schaffer B, et al. Lymphangiograms: Their diagnostic and therapeutic potential. Radiology 1961;76:179-99.

(23.) Klutmann S, Bohuslavizki KH, Hoft S, et al. [Lymphoscintigraphy with double tracer technique in carcinomas of the head-neck region]. Laryngorhinootologie 1997;76:740-4.

(24.) Pitman KT, Johnson JT, Edington H, et al. Lymphatic mapping with isosulfan blue dye in squamous cell carcinoma of the head and neck. Arch Otolaryngol Head Neck Surg 1998;124:790-3.

(25.) Shoaib T, Soutar DS, Prosser JE, et al. A suggested method for sentinel node biopsy in squamous cell carcinoma of the head and neck. Head Neck 1999;21:728-33.

(26.) Koch WM, Choti MA, Civelek AC, et al. Gamma probe-directed biopsy of the sentinel node in oral squamous cell carcinoma. Arch Otolaryngol Head Neck Surg 1998;124:455-9.

(27.) Werner JA, Dunne AA, Brandt D, et al. [Studies on significance of sentinel lymphadenectomy in pharyngeal and laryngeal carcinoma]. Laryngorhinootologie 1999;78:663-70.

(28.) Alex JC, Sasaki CT, Krag DN, et al. Sentinel lymph node radio-localization in head and neck squamous cell carcinoma. Laryngoscope 2000;110:198-203.

(29.) Chiesa F, Mauri S, Grana C, et al. Is there a role for sentinel node biopsy in early NO tongue tumors? Surgery 2000;128:16-21.

(30.) Zitsch RP III, Todd DW, Renner GJ, Singh A. Intraoperative radiolymphoscintigraphy for detection of occult nodal metastasis in patients with head and neck squamous cell carcinoma. Otolaryngol Head Neck Surg 2000;122:662-6.

(31.) Colnot DR, Nieuwenhuis EJ, van den Brekel MW, et al. Head and neck squamous cell carcinoma: US-guided fine-needle aspiration of sentinel lymph nodes for improved staging--initial experience. Radiology 2001;218:289-93.

(32.) Taylor RJ, Wahl RL, Sharma PK, et al. Sentinel node localization in oral cavity and oropharynx squamous cell cancer. Arch Otolaryngol Head Neck Surg 2001;127:970-4.

(33.) Bilchik AJ, Giuliano A, Essner R, et al. Universal application of intraoperative lymphatic mapping and sentinel lymphadenectomy in solid neoplasms. Cancer J Sci Am 1998;4:351-8.

(34.) Shoaib T, Soutar DS, MacDonald DG, et al. The accuracy of head and neck carcinoma sentinel lymph node biopsy in the clinically NO neck. Cancer 2001;91:2077-83.

(35.) Mozzillo N, Chiesa F, Botti G, et al. Sentinel node biopsy in head and neck cancer. Ann Surg Oncol 2001;8(9 Suppl):103S-105S.

(36.) Meijer S, van den Brekel MW, Nieuwenhuis EJ. A suggested method for sentinel node biopsy in SCC of the head and neck [letter]. Head Neck 2000;22:733-5.

(37.) American Joint Committee on Cancer. Cancer Staging Handbook. 5th ed. Philadelphia: Lippincott-Raven, 1998:51-5.

From the Roswell Park Cancer Institute, Buffalo, N.Y.

Reprint requests: Nestor R. Rigual, MD, Department of Head and Neck Surgery, Roswell Park Cancer Institute, Elm and Carlton Sts., Buffalo, NY 14263. Phone:(716)845-3158; fax:(716) 845-8646; e-mail: nestor.rigual@roswellpark.org
COPYRIGHT 2002 Medquest Communications, LLC
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2002, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Comment:Sentinel lymph node biopsy in SCC of the head and neck: A major advance in staging the NO neck.
Author:Rigual, Nestor R.
Publication:Ear, Nose and Throat Journal
Article Type:Brief Article
Geographic Code:1USA
Date:Mar 1, 2002
Words:4054
Previous Article:The radiologic work-up in thyroid surgery: Fine-needle biopsy versus scintigraphy and ultrasound.
Next Article:Enzyme-potentiated desensitization in otolaryngic allergy.
Topics:


Related Articles
Kimura's disease: A case report.
Management of the unknown primary in patients with metastatic cancer of the head and neck.
Superficial leiomyosarcoma of the head and neck: Case report and review of the literature.
Options for preserving the larynx in patients with advanced laryngeal and hypopharyngeal cancer. (Original Article).
SUR2 Prevalence of teaching sentinel lymph node biopsy for breast cancer in general surgery residency programs. (Surgery).
Positive response of advanced oropharyngeal cancer with trismus to chemoradiation. (Letters to the Editor).
Expression of EphB4 in head and neck squamous cell carcinoma.
Successful treatment of head and neck cancer involving the prevertebral fascia.
The use of combined PET/CT for localizing recurrent head and neck cancer: the Pittsburgh experience.
Lymph node biopsy specimens and diagnosis of cat-scratch disease.

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters