Printer Friendly

Utility of intraoperative frozen sections during thyroid surgery.

1. Introduction

The incidence of thyroid cancer increased 2.4-fold from 3.6 to 8.7 per 100,000 Americans [1] over a thirty-year period ending in 2002. The annual incidence of palpable thyroid nodules in North America is 0.1% [2] and most of those under 1 cm cannot be detected by physical exam alone [3]. The introduction of high resolution ultrasound technology has increased our ability to diagnose thyroid nodules [4]. A patient of male gender, aged <20 years or >70 years, with a family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia (MEN), rapid nodular growth, a firm or fixed nodule, a history of head and neck irradiation, a nodule that is >4 cm or is partially cystic, or a compressive sensation should raise increased suspicion for thyroid carcinoma [5].

In 2009, the Bethesda Criteria for Reporting Thyroid Cytopathology were published to create a common language by which multidisciplinary teams could accurately discuss the diagnosis and implications of a fine needle aspiration (FNA) biopsy [6]. The six categories found within the Bethesda Criteria each implies a different malignancy risk (Table 1) and treatment approaches ranging from watchful waiting to total thyroidectomy with postoperative radioactive iodine.

FNA biopsies with a diagnosis of follicular neoplasm, suspicious for follicular neoplasm, or suspicious for malignancy carry a 15-75% chance of malignancy [6]. Unfortunately, it is difficult to distinguish between follicular adenoma and follicular carcinoma based solely on an FNA biopsy because histologic evidence of capsular and/or vascular invasion is required to determine malignancy for a follicular lesion [7]. Approximately 30% of these FNA biopsies showing follicular lesions prove to be malignant on histologic examination [8]. A diagnostic thyroid lobectomy provides the tissue necessary for a pathologic diagnosis.

In thyroid surgery, intraoperative FS is used to assist in further surgical treatment at this point in care, with good concordance rates between FNA results and FS in the setting of papillary thyroid carcinoma [9]. However, FS is usually insufficient to determine true capsular or vascular invasion and deferral to a final pathologic diagnosis is often necessary in the setting of a follicular lesion [10]. The use of intraoperative FS has long been debated secondary to concerns about increased cost and operative time without a true consensus [11].

The overall objective of this study was to describe the usefulness of intraoperative FS in the diagnosis and treatment of thyroid nodules where FNA biopsies have evidence of follicular neoplasm. This was achieved by (1) determining the sensitivity and specificity of FS with both FNA and final pathology, (2) assessing the added benefit of FS to information obtained from the FNA, and (3) calculating the positive predictive value (PPV) and negative predictive value (NPV) of FS as a tool for intraoperative decision making.

2. Materials and Methods

This retrospective chart review was approved by the Duke University School of Medicine Institutional Review Board. The review was performed on patients who have been evaluated and treated for a thyroid nodule within the Duke University Health System after the initiation of the Bethesda System for Reporting Thyroid Cytopathology in 2009. Our inclusion criteria required that a fine needle aspiration biopsy and an operative procedure with intraoperative frozen section and final pathology be performed at our tertiary care center. Our exclusion criteria included an FNA biopsy diagnostic of malignancy (e.g., papillary carcinoma), nondiagnostic/unsatisfactory FNA samples, FNA reports not in congruence with the Bethesda Criteria, and a history of irradiation to the head and neck.

FNA and intraoperative FS results were compared with final pathology. An FNA specimen was considered "suggests negative" if it was reported as "benign", "negative," or of "undetermined significance." An FNA specimen was "suggests positive" if it showed "follicular neoplasm", "suspicious for follicular neoplasm," or "suspicious for malignancy". Reports showing "Hurthle cell" within the description were considered to be part of the "follicular neoplasm" category. An FS specimen was considered "suggests negative" if the pathologist reported "benign", "adenoma", "negative for malignancy", "nodular hyperplasia", or "goiter". An FS specimen was considered "suggests positive" for reports of "follicular lesion", "follicular neoplasm", "suspicious for carcinoma/malignancy", "atypical features", or "defer". Final pathology was deemed positive if malignancy was found, regardless of size (i.e., incidentally found microcarcinoma). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated.

3. Results and Discussion

A total of 93 patients met inclusion criteria with 72 females (77.4%) and 21 males (22.6%). Median age was 51.9 years with a range between 9 and 76. One patient had two suspicious lesions which were analyzed, resulting in 94 thyroid nodules available for statistical analysis.

Table 2 shows the stratification of FNA results that were available for analysis. No patients had FNA reporting malignancy or nondiagnostic/unsatisfactory per study design. There were 32 samples that were read as atypia or follicular lesion of undetermined significance and 26 samples read as follicular neoplasm or suspicious for follicular neoplasm. The rest were read as either benign or suspicious for malignancy (34 and 2 samples, resp.). Despite the 0-3% risk of malignancy for benign diagnostic category, there were additional indications for surgery including suspicious ultrasound findings, compressive symptoms, persistent growth, or even patient preference. There were four patients noted to have nondiagnostic/insufficient FNA biopsies, one with a negative FS and positive final pathology (papillary carcinoma), two with FS suggesting positive although final pathology was negative, and one with both negative FS and final pathology. There were 2 patients who were diagnostic malignancy where their FS and final pathology were both positive (papillary carcinoma and metastatic melanoma).

Table 3 shows each patient and the correlation between the FNA Bethesda Criteria, FS, and final pathology. The sensitivity and specificity of FS were 76.9% and 67.9%, respectively. This is compared to the sensitivity and specificity for FNA, which were 53.8% and 74.1%, respectively. The PPV and NPV for FS were 27.8% and 94.8%, respectively. In comparison, FNA demonstrated a PPV of 25% and NPV of 90.9%. There were no changes in operative course as a consequence of a FS result.

Our study did not demonstrate added information when intraoperative FS was used in patients with an FNA of benign, follicular neoplasm, suspicious for follicular neoplasm, or suspicious for malignancy reading. With this information, patients can be scheduled for a thyroid lobectomy with the knowledge that a diagnosis of malignancy will not be obtained until final pathologic analysis is completed. If malignancy is determined, a completion thyroidectomy can then be scheduled. The time and expense of intraoperative FS and scheduling operating room time for a total thyroidectomy, when it is not initially indicated, can therefore be spared.

The initiation of the Bethesda Criteria for Reporting Thyroid Cytopathology has greatly improved our ability to have accurate and meaningful conversations with our patients about their thyroid disease. In our case series, the sensitivity of FS was 76.9% compared to 53.8% for FNA, which is lower than previously published data [9, 12, 13]. However, these publications were performed prior to the Bethesda Criteria and this may account for these differences. Even when evaluating only patients with a diagnosis of malignancy, Makay et al. observed FS to only have a 72% sensitivity [14]. The PPV of both the FS and FNA biopsy were 27.8% and 25%, respectively. The challenges of FNA interpretation are well known and documented. Chang and colleagues [13] showed that when there was discrepancy between the FNA and FS, the FS was shown to be more accurate (78.9% versus 21.1%).

Our results indicate that the addition of an FS does not allow for a more accurate and predictive result. There were no instances within our series where the FS altered the clinical course (i.e., conversion to a total thyroidectomy). There were no false positive results of malignancy for our FSs while there were two false negatives, one with a papillary microcarcinoma and the other a follicular carcinoma.

Future directions for the diagnosis and treatment of thyroid nodules should include addressing highly variable language used among pathologists in regard to thyroid intraoperative FS reporting; diagnosis may benefit from a more uniform language akin to that instituted for FNA biopsies. A standardized language may assist pathologists in their assessment as well as helping surgeons make decisions while in the operative theatre.

4. Conclusion

Our data does not support the clinical usefulness of FS for FNA biopsies with the diagnosis of follicular neoplasm, suspicious for follicular neoplasm, or suspicious for malignancy at our institution. As such, decision for completion thyroidectomy should be determined by the final pathology. This data is useful for both counseling patients with thyroid lesions and subsequent surgical planning.

http://dx.doi.org/10.1155/2013/496138

Conflict of Interests

The authors declare that they have no conflict of interests.

References

[1] L. Davies and H. G. Welch, "Increasing incidence of thyroid cancer in the United States, 1973-2002," Journal of the American Medical Association, vol. 295, no. 18, pp. 2164-2167, 2006.

[2] G. Popoveniuc and J. Jonklass, "Thyroid nodules," Medical Clinics of North America, vol. 96, no. 2, pp. 329-349, 2012.

[3] G. H. Tan and H. Gharib, "Thyroid incidentalomas: management approaches to nonpalpable nodules discovered incidentally on thyroid imaging," Annals of Internal Medicine, vol. 126, no. 3, pp. 226-231,1997

[4] P. W. Wiest, M. F. Hartshorne, P. D. Inskip et al., "Thyroid palpation versus high-resolution thyroid ultrasonography in the detection of nodules," Journal of Ultrasound in Medicine, vol. 17, no. 8, pp. 487-496,1998.

[5] L. Hegedus, "Clinical Practice. The thyroid nodule," The New England Journal of Medicine, vol. 351, no. 17, pp. 1764-1771,2004.

[6] E. S. Cibas and S. Z. Ali, "The bethesda system for reporting thyroid cytopathology," Thyroid, vol. 19, no. 11, pp. 1159-1165, 2009.

[7] T. Davidov, S. Z. Trooskin, B. A. Shanker et al., "Routine second-opinion cytopathology review of thyroid fine needle aspiration biopsies reduces diagnostic thyroidectomy," Surgery, vol. 148, no. 6, pp. 1294-1299, 2010.

[8] Z. W. Baloch, S. Fleisher, V. A. LiVolsi, and P. K. Gupta, "Diagnosis of ''follicular neoplasm": a gray zone in thyroid fine+needle aspiration cytology," Diagnostic Cytopathology, vol. 26, no. 1, pp. 41-44, 2002.

[9] B. Cetin, S. Aslan, C. Hatiboglu et al., "Frozen section in thyroid surgery: is it a necessity?" Canadian Journal of Surgery, vol. 47, no. 1, pp. 29-33, 2004.

[10] V. A. LiVolsi and Z. W. Baloch, "Use and abuse of frozen section in the diagnosis of follicular thyroid lesions," Endocrine Pathology, vol. 16, no. 4, pp. 285-294, 2005.

[11] M. C. Miller, C. J. Rubin, M. Cunnane et al., "Intraoperative pathologic examination: cost effectiveness and clinical value in patients with cytologic diagnosis of cellular follicular thyroid lesion," Thyroid, vol. 17, no. 6, pp. 557-565, 2007

[12] D. L. Mandell, E. M. Genden, J. I. Mechanick, D. A. Bergman, H. F. Biller, and M. L. Urken, "Diagnostic accuracy of fine-needle aspiration and frozen section in nodular thyroid disease," Otolaryngology-Head and Neck Surgery, vol. 124, no. 5, pp. 531536, 2001.

[13] H. Y. Chang, J. D. Lin, J. F. Chen et al., "Correlation of fine needle aspiration cytology and frozen section biopsies in the diagnosis of thyroid nodules," Journal of Clinical Pathology, vol. 50, no. 12, pp. 1005-1009,1997

[14] O. Makay, G. Icoz, B. Gurcu et al., "The ongoing debate in thyroid surgery: should frozen section analysis be omitted?" Endocrine Journal, vol. 54, no. 3, pp. 385-390, 2007

Russel Kahmke, (1) Walter T. Lee, (1,2) Liana Puscas, (1,2) Richard L. Scher, (1) Michael J. Shealy, (3) Warner M. Burch, (4) Ramon M. Esclamado (1)

(1) Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, Duke University Medical Center, Duke University, Durham, NC27710, USA

(2) Section of Otolaryngology-Head and Neck Surgery, Department of Surgery, Durham VA Medical Center, Durham, NC 27705, USA

(3) Division of Pathology Clinical Services, Department of Pathology, Duke University Medical Center, Duke University, Durham,

NC 27710, USA

(4) Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke University Medical Center, Duke University, Durham, NC 27710, USA

Correspondence should be addressed to Walter T. Lee; walter.lee@duke.edu

Received 28 October 2012; Revised 3 January 2013; Accepted 3 January 2013

Academic Editor: Richard L. Doty

TABLE 1: Fine needle aspiration biopsy diagnostic
categories, adapted from Cibas and Ali (The Bethesda System
for Thyroid Cytopathology) [6].

Diagnostic category                 Risk of malignancy (%)

Nondiagnostic or unsatisfactory     1-4
Benign                              0-3
Atypia or follicular lesion of
  undetermined significance         5-15
Follicular neoplasm or suspicious
  for follicular neoplasm           15-30
Suspicious for malignancy           60-75
Malignant                           97-99

TABLE 2: Stratification of fine needle aspiration biopsies
according to Bethesda system.

                                                   Number of
Diagnostic category                                samples

Non-diagnostic or unsatisfactory                   0
Benign                                             34
Atypia or follicular lesion of undetermined
  significance                                     32
Follicular neoplasm or suspicious for follicular
  neoplasm                                         26
Suspicious for malignancy                          2
Malignant                                          0

TABLE 3: Fine needle aspiration (FNA) Bethesda Criteria and
frozen section (FS) compared with final pathology.

FNA        Frozen     Final
           section    pathology

           Negative   Negative    19
Benign                Positive    1    FVPC
           Positive   Negative    12
                      Positive    2    FVPC x2
           Negative   Negative    19   Follicular ca
AUS/FLUS              Positive    1
           Positive   Negative    10
                      Positive    3    Follicular ca,
                                         FVPC, micropapillary ca
           Negative   Negative    14   Micropapillary ca
FN/SFN                Positive    1
           Positive   Negative    6
                      Positive    5    Papillary ca,
                                         micropapillary ca x2,
                                         FVPC, Hurthle cell ca
           Negative   Negative
SM                    Positive    1 0
           Positive   Negative    1 0
                      Positive

AUS/FLUS: atypia/follicular lesion of undetermined
significance; FN/SFN: follicular neoplasm or suspicious for
follicular neoplasm; SM: suspicious for malignancy; FNA:
fine needle aspiration biopsy; FVPC: follicular variant of
papillary carcinoma; ca: carcinoma.
COPYRIGHT 2013 Hindawi Limited
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2013 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:Clinical Study
Author:Kahmke, Russel; Lee, Walter T.; Puscas, Liana; Scher, Richard L.; Shealy, Michael J.; Burch, Warner
Publication:International Journal of Otolaryngology
Article Type:Report
Date:Jan 1, 2013
Words:2258
Previous Article:Clinical and pathological characteristics of organized hematoma.
Next Article:HPV prevalence and prognostic value in a prospective cohort of 255 patients with locally advanced HNSCC: a single-centre experience.
Topics:

Terms of use | Privacy policy | Copyright © 2020 Farlex, Inc. | Feedback | For webmasters