The role of intraoperative frozen section if suspicious for papillary thyroid cancer

Combined fine-needle aspiration and selective intraoperative frozen section to optimize prediction of malignant thyroid nodules: A retrospective cohort study of more than 3000 patients

BACKGROUND

Preoperative fine-needle aspiration (FNA) is widely used to differentiate malignant from benign thyroid nodules, while intraoperative frozen sections (FS) are suggested as a systematic supplement for intraoperative decision-making, but limitations still remain for both procedures.

METHODS

Medical records of 3807 patients with thyroid nodules who underwent both pathological diagnoses (FS and FNA) at our hospital were reviewed. The diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FNA and FS were also evaluated. We further designed an optimal integration scheme (FNA+selective FS) to predict thyroid nodule malignancy. Finally, the efficiency of the proposed integrated diagnostic model was validated using an independent external cohort.

RESULTS

For distinguishing malignant nodules, FNA had an accuracy of 90.3%, sensitivity of 90.7%, specificity of 85.2%, PPV of 98.8% and NPV of 40.4%. In contrast, the FS represented higher discriminative power (Accuracy, 94.5%; Sensitivity, 94.1%; Specificity, 100%; PPV, 100%; and NPV, 55.6%). we proposed the selective usage of FS (removed nodules with Bethesda category VI from routine FS, ~1/3 of total). The integrated new diagnostic model of FNA plus selective FS (FNA+sFS) achieved accuracy of 96.9%, sensitivity of 97.3%, specificity of 92%, PPV of 99.4%, and NPV of 71.6% (NRI=0.135, 95% CI 0.103-0.167, P <0.001) and was successfully applied to an external cohort (N=554).

CONCLUSION

Compared with the FNA diagnostic system, FS has an increased ability to distinguish benign and malignant thyroid nodules. The newly proposed integrated diagnostic model of FNA + selective FS can optimize the accuracy of diagnosis.

Utility of intraoperative frozen sections of thyroid tissue in the age of molecular testing

OBJECTIVES

Our study aims to examine the correlation between preoperative ultrasound-guided fine-needle aspiration and intraoperative frozen section and examine the clinical benefit of frozen section in the context of the latest national guidelines on the management of differentiated thyroid cancer.

STUDY DESIGN

A retrospective review of thyroid frozen section from 2012 to2017 at one institution.

SETTING

Tertiary care centre.

PARTICIPANTS/MAIN OUTCOME

Patient demographics, fine-needle aspiration results, molecular testing results, frozen section diagnosis (classified as benign, indeterminate, or malignant), final pathologic diagnosis, initial planned surgery, actual surgery performed, need for additional surgery and complications were recorded. Complications included hematoma formation, hypocalcaemia (requiring readmission, symptomatic, or >24-hour stay post op) and recurrent or superior laryngeal nerve damage.

RESULTS

728 total patients had an intraoperative frozen section performed. A Thy 4/Bethesda V USGFNA diagnosis (n = 55) significantly correlated with a clinically important intraoperative frozen section (n = 17, P < .01). Intraoperative management was changed by the frozen section 53 times (7.2%). Molecular testing was sent on 92 USGFNA specimens, 80 of which were deemed "suspicious." Of the 49 patients whose management was upstaged intraoperatively, 29 (59%) would not necessitate a completion thyroidectomy under the latest UK and ATA guidelines based on final pathology.

CONCLUSION

Intraoperative frozen sections rarely alter the pre-surgical plan and indeed may result in expanded surgery that could have been avoided based on latest UK and US guidelines. Molecular testing of indeterminate fine-needle aspiration results does not appear to predict meaningful intraoperative frozen section results.

Utility of Routine Frozen Section of Thyroid Nodules Classified as Follicular Neoplasm

OBJECTIVES

To evaluate the diagnostic performance of frozen section in thyroid nodules classified as follicular neoplasm.

METHODS

A diagnostic test meta-analysis was designed. Studies that assessed frozen section in patients with thyroid nodules and a fine-needle aspiration biopsy result of Bethesda IV were selected. The outcomes measured were the number of false- and true-positive and -negative results. We used the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) instrument for methodological quality assessment and a bivariate mixed-effects regression framework and a likelihood-based estimation of the exact binomial approach.

RESULTS

Forty-six studies from 1991 to 2018 were included. Most studies had moderate methodological quality. The overall sensitivity and specificity were 43% (95% confidence internal [CI], 0.34-0.53) and 100% (95% CI, 0.99-1.00), respectively. The hierarchic summary receiver operating characteristic curve showed an area under the curve of 0.91 (95% CI, 0.80-0.97).

CONCLUSIONS

Frozen section demonstrates moderate diagnostic performance in patients with follicular neoplasm, and its utility for making intraoperative decisions is limited. Its routine use should be discouraged.

Role of frozen section in the surgical management of indeterminate thyroid nodules

Indeterminate thyroid nodules (ITNs) correspond to the categories III (atypia of undetermined significance or follicular lesion of undetermined significance) and IV (follicular neoplasm or suspicious for a follicular neoplasm) of the Bethesda system for reporting thyroid cytopathology. Their malignancy risk is 5-15% and 15-30% respectively, imposing surgical treatment for definitive diagnosis. Thus, they represent a diagnostic and therapeutic challenge given the risk of over or under treatment. Several teams continue to perform systematic intraoperative frozen sections (FS) in order to guide the initial extent of surgery and to avoid a two-stage thyroidectomy. FS have a very high specificity and positive predictive value for the diagnosis of malignancy allowing a one-stage total thyroidectomy if the result is positive. However, this attitude is highly controversial; and this review of the literature demonstrates that FS is of little contribution in this setting, due to low sensitivity and high false-negative rates. In fact, for these lesions, a careful and comprehensive evaluation of the tumor capsule is mandatory in order to visualize a capsular or a vascular invasion permitting to make the diagnosis of malignancy. However, this assessment is only possible on permanent section. Moreover, FS can jeopardize the detection of signs of capsular invasion on final pathologic examination. The recent development of molecular testing results in a better preoperative diagnosis, thus reducing even more the need for intraoperative FS. Contrasting with their limited role in Bethesda III and IV categories, FS are useful in guiding the preoperative management of Bethesda V category nodules, given their high negative and positive predictive values. Intraoperative FS of ITNs are of little use and are not recommended systematically. Their use should be restricted to elderly, high anesthetic risk, or poorly compliant patients for whom an eventual subsequent complementary surgery may be problematic.

Is Frozen-Section Analysis During Thyroid Operation Useful in the Era of Molecular Testing?

BACKGROUND

With the increased use of molecular testing of thyroid fine-needle biopsies, the frequency and extent of thyroid resection for thyroid nodules has changed. Although the role of frozen-section analysis of the thyroid has been reduced markedly in recent years, many surgeons still routinely use it intraoperatively. We sought to determine the utility of frozen section during thyroidectomy in the era of molecular testing.

STUDY DESIGN

We reviewed 236 consecutive patients who had thyroidectomy with intraoperative frozen-section analysis at our institution between November 2015 and October 2017. We re-reviewed the preoperative diagnosis, frozen-section diagnosis, final pathology, and whether operative management changed from the initial plan based on frozen section.

RESULTS

Mean age of the patients was 55.6 ± 14.1 years, and 83% were female. Of the 236 patients, frozen section did not change the intraoperative management in 225 (95%). Of the 11 patients whose thyroid operation was modified, the operation was either too much or not enough in 6 patients. In only 5 (2.1%) patients, frozen-section analysis correctly changed the extent of thyroidectomy.

CONCLUSIONS

Thyroid frozen-section analysis adds cost and time to thyroid operations without notable benefit. In our cohort, only 2.1% of frozen sections accurately changed intraoperative management. We recommend against its routine use.

Calcitonin measurement in fine-needle aspirate washout fluid by electrochemiluminescence immunoassay for thyroid tumors

Purpose

For the differential diagnosis of medullary thyroid carcinoma (MTC) on thyroid nodules, ultrasound-guided fine-needle aspiration cytology is a useful and safe procedure, but its diagnostic accuracy is not high enough. As an ancillary method to accurately diagnose MTC, the calcitonin in fine-needle aspirate washout fluid (FNA-Ct) is used. However, no data are available about cut-off values of FNA-Ct using the currently available electrochemiluminescence immunoassay (ECLIA).

Methods

We investigated 180 thyroid nodules in 141 patients. After smearing, the syringe and needle used for the FNA were rinsed with normal saline (0.5 mL). The calcitonin in the washout was measured by ECLIA.

Results

The FNA-Ct in the non-MTC nodules of MTC patients, non-MTC nodules of non-MTC patients, and MTC nodules were 10.6-2100 pg/mL (median 24.6 pg/mL), < 0.5-21.0 pg/mL (median < 0.5 pg/mL), and 94.9-4,070,000 pg/mL (median 177,000 pg/mL), respectively. A receiver operating characteristic analysis of the MTC nodules and the non-MTC nodules of the non-MTC patients indicated that the cut-off value was 21.0 pg/mL, leading to 100% sensitivity and 100% specificity.

Conclusions

This is the first study to determine the cut-off value of FNA-Ct with an ECLIA, and we propose that the optimal cut-off value is 21.0 pg/mL.

Utility of Intraoperative Frozen Section in Large Thyroid Nodules

OBJECTIVE

To determine if the routine use of intraoperative frozen section (iFS) results in cost savings among patients with nodules >4 cm with nonmalignant cytology undergoing a thyroid lobectomy.

STUDY DESIGN

Case series with chart review; cost minimization analysis.

SETTING

Single academic center.

SUBJECTS AND METHODS

Records were reviewed on a consecutive sample of 48 patients with thyroid nodules >4 cm and nonmalignant cytology who were undergoing thyroid lobectomy in which iFS was performed between 2010 and 2015. A decision tree model of thyroid lobectomy with iFS was created. Comparative parameters were obtained from the literature. A cost minimization analysis was performed comparing lobectomy with and without iFS and the need for completion thyroidectomy with costs estimated according to 2014 data from Medicare, the Bureau of Labor Statistics, and the Nationwide Inpatient Sample.

RESULTS

The overall malignancy rate was 25%, and 33% of these malignancies were identified intraoperatively. When the malignancy rates obtained from our cohort were applied, performing routine iFS was the less costly scenario, resulting in a savings of $486 per case. When the rate of malignancy identified on iFS was adjusted, obtaining iFS remained the less costly scenario as long as the rate of malignancies identified on iFS exceeded 12%. If patients with follicular lesions on cytology were excluded, 50% of malignancies were identified intraoperatively, resulting in a savings of $768 per case.

CONCLUSIONS

For patients with nodules >4 cm who are undergoing a diagnostic lobectomy, the routine use of iFS may result in decreased health care utilization. Additional cost savings could be obtained if iFS is avoided among patients with follicular lesions.

Economic Impact of Frozen Section for Thyroid Nodules with "Suspicious for Malignancy" Cytology

Objective To perform a cost analysis of the routine use of intraoperative frozen section (iFS) among patients undergoing a thyroid lobectomy with "suspicious for malignancy" (SUSP) cytology in the context of the 2015 American Thyroid Association guidelines. Study Design Case series with chart review; cost minimization analysis. Setting Academic. Subjects and Methods Records were reviewed for patients with SUSP cytology who underwent thyroid surgery between 2010 and 2015 in which iFS was utilized. The diagnostic test performance of iFS and the frequency of indicated completion/total thyroidectomies based on the 2015 guidelines were calculated. A cost minimization analysis was performed comparing lobectomy, with and without iFS, and the need for completion thyroidectomy according to costs estimated from 2014 data from Medicare, the Bureau of Labor Statistics, and the Nationwide Inpatient Sample. Results Sixty-five patients met inclusion criteria. The malignancy rate was 61.5%, 45% of which was identified intraoperatively. The specificity and positive predictive value were 100%. The negative predictive value and sensitivity were 83% and 95%, respectively. Completion/total thyroidectomy was indicated for 9% of patients; 83% of these individuals had findings on iFS that would have changed management intraoperatively. Application of the new guidelines would have resulted in a significant reduction in the frequency of conversion to a total thyroidectomy when compared with the actual management (26.1% vs 7.7%, P = .005). Performing routine iFS was the less costly scenario, resulting in a savings of $474 per case. Conclusion For patients with SUSP cytology undergoing lobectomy, routine use of iFS would result in decreased health care utilization.

Fine-needle aspiration cytology for medullary thyroid carcinoma: a single institutional experience in Japan

Many cytological studies on medullary thyroid carcinoma (MTC) have been reported; however, such studies in large series of patients with MTC have not been performed. We investigated MTC at a single institution in Japan using fine-needle aspiration cytology (FNAC), and aimed to establish a preoperative diagnostic algorithm for MTC. FNAC was performed in 119 of 149 patients with MTC (79.9%) who ultimately underwent surgical resection. Moreover, 22 of 56 hereditary MTC (39.3%) were diagnosed preoperatively without FNAC by their high serum calcitonin levels or increased response to calcium stimulation (11 cases each), as well as RET mutation analysis. On FNAC, 76.5% of nodules were categorized as 'malignancy' or 'suspicious for malignancy'. The sensitivity and specificity of calcitonin measurement in aspiration needle wash-out fluid and in immunocytochemical staining for calcitonin were 96.3% and 92.3% respectively. We proposed an algorithm for preoperative diagnosis of MTC utilizing FNAC: When thyroid nodules are highly suspicious for MTC by their clinical and ultrasonographic features, serum calcitonin measurement with or without a calcium stimulation test is required. Furthermore, FNAC should be performed for patients who do not have those findings. When there is a possibility of MTC at the time of FNAC, calcitonin measurement using needle wash-out fluid is a reliable diagnostic tool. When MTC is suspected on cytological examination, immunocytochemical staining for calcitonin is useful for confirming MTC diagnosis.

Adult Thyroglossal Duct Carcinoma of Thyroid Epithelial Origin: A Retrospective Observational Study

Thyroglossal duct or cyst carcinoma (TGDCCa) is uncommon. Current treatments follow those of thyroid cancer but controversy exists over the extent of thyroid and lymph node surgery. Our aim was to study the presentation, treatment strategies and clinical outcomes in patients presenting with TGDCCa. Of 637 patients diagnosed with thyroid cancer over 15-years, 4 patients (0.6 %) with TGDCCa were identified. Two patients were diagnosed outside this time period. Details of demographics, presentation, diagnosis, management and outcomes of all 6 patients were reviewed. 5 females and 1 male with a median (range) age of 41 (21-70) years were treated for TGDCCa. Five patients were diagnosed after initial surgery for thyroglossal cyst-cyst excision (n = 2) and Sistrunk's procedure (n = 3). This was followed by a total thyroidectomy (TT) in 4 of these patients. One patient underwent Sistrunk's operation, total thyroidectomy and central neck dissection at the first operation. I131 therapy was used in patients who had TT. Three patients had additional tumour foci in the thyroid. However, lymph node recurrence occurred in 2 patients at 6 and 16 months. At a median follow up of 55 months, all 6 patients were disease free. All patients had papillary TGDCCa and did well with conventional treatment as for thyroid cancer. The extent of treatment required is debatable as half the patients had additional thyroid foci and no patient had clinically or radiologically involved lymph nodes at presentation. A systematic review of published cases will help summarise the existing knowledge base.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ASSOCIAZIONE MEDICI ENDOCRINOLOGI MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND MANAGEMENT OF THYROID NODULES--2016 UPDATE

Thyroid nodules are detected in up to 50 to 60% of healthy subjects. Most nodules do not cause clinically significant symptoms, and as a result, the main challenge in their management is to rule out malignancy, with ultrasonography (US) and fine-needle aspiration (FNA) biopsy serving as diagnostic cornerstones. The key issues discussed in these guidelines are as follows: (1) US-based categorization of the malignancy risk and indications for US-guided FNA (henceforth, FNA), (2) cytologic classification of FNA samples, (3) the roles of immunocytochemistry and molecular testing applied to thyroid FNA, (4) therapeutic options, and (5) follow-up strategy. Thyroid nodule management during pregnancy and in children are also addressed. On the basis of US features, thyroid nodules may be categorized into 3 groups: low-, intermediate-and high-malignancy risk. FNA should be considered for nodules ≤10 mm diameter only when suspicious US signs are present, while nodules ≤5 mm should be monitored rather than biopsied. A classification scheme of 5 categories (nondiagnostic, benign, indeterminate, suspicious for malignancy, or malignant) is recommended for the cytologic report. Indeterminate lesions are further subdivided into 2 subclasses to more accurately stratify the risk of malignancy. At present, no single cytochemical or genetic marker can definitely rule out malignancy in indeterminate nodules. Nevertheless, these tools should be considered together with clinical data, US signs, elastographic pattern, or results of other imaging techniques to improve the management of these lesions. Most thyroid nodules do not require any treatment, and levothyroxine (LT4) suppressive therapy is not recommended. Percutaneous ethanol injection (PEI) should be the first-line treatment option for relapsing, benign cystic lesions, while US-guided thermal ablation treatments may be considered for solid or mixed symptomatic benign thyroid nodules. Surgery remains the treatment of choice for malignant or suspicious nodules. The present document updates previous guidelines released in 2006 and 2010 by the American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE) and Associazione Medici Endocrinologi (AME).

Intraoperative Frozen Section in “Suspicious for Papillary Thyroid Carcinoma” after Adoption of the Bethesda System

Objective

To evaluate the accuracy and utility of intraoperative frozen section examination (iFSE) in patients with a preoperative fine-needle aspiration (FNA) cytology of “suspicious for malignancy” (SFM)–Bethesda V, after the adoption of the Bethesda System for Reporting Thyroid Cytopathology.

Study Design

Case series with chart review.

Setting

Tertiary medical center.

Subjects and Methods

All patients with SFM–Bethesda V who underwent thyroid surgery with iFSE between 2010 and 2015 were included. In cases where the iFSE was reported to be malignant, a total thyroidectomy was performed; otherwise, thyroid lobectomy (hemithyroidectomy) was performed.

Results

The current series included 47 patients diagnosed preoperatively with FNA cytology of SFM–Bethesda V. The malignancy rate was 74.5% (35 of 47). Twenty-four patients with nonmalignant iFSE results underwent lobectomy during their initial surgery: 12 were subsequently found with benign final histology and did not undergo completion thyroidectomy; the other 12 patients had malignant results on final histology, but only 4 of them underwent completion thyroidectomy. iFSE resulted in a sensitivity and specificity of 65.7% and 100%, respectively, with a positive predictive value of 100% (23 of 23) and a negative predictive value of 50% (12 of 24). Accuracy of the iFSE methodology was 74.5% (35 of 47).

Conclusions

With no significant preoperative clinical or sonographic predictors for thyroid malignancy and given the high specificity of iFSE, our results support the use of iFSE for patients with preoperative FNA cytology of SFM–Bethesda V who are undergoing thyroid surgery, to determine the extent of required surgery.

Management of Thyroid Nodular Disease: Current Cytopathology Classifications and Genetic Testing

Preoperative diagnosis and operative planning for patients with thyroid nodules has improved over the last decade. The Bethesda criteria for cytopathologic classification of thyroid nodule aspirate has enhanced communication between pathologists and clinicians. Multiple genetic tests, including molecular markers and the Afirma gene expression classifier, have been developed and validated. The tests, along with clinical and radiologic information, are most useful in the setting of indeterminate cytology. The development of an updated diagnostic and treatment algorithm incorporating all available tests will help standardize the management of patients with nodular thyroid disease and reduce variation and inefficiencies in care.

Analysis of an institutional protocol for thyroid lobectomy: Utility of routine intraoperative frozen section and expedited (overnight) pathology

BACKGROUND

Intraoperative frozen section (FS) often is performed in patients who undergo thyroid lobectomy to determine the need for completion thyroidectomy. At our institution, if FS pathology is benign, final pathology is expedited overnight. The aim of this study was to determine the utility of FS and to identify a cost-effective management algorithm for thyroid lobectomy.

METHODS

A retrospective review was performed of patients who underwent thyroid lobectomy between January 2009 and May 2013. Preoperative cytology ranged from "benign" to "suspicious for malignancy." Clinically significant cancers were defined as >1 cm in size, or multifocal microcarcinomas.

RESULTS

Of the 192 patients who underwent thyroid lobectomy with FS, FS was suspicious for malignancy in 5 (3%) patients; 1 (0.5%) underwent immediate completion thyroidectomy. On final pathology, 9 (5%) patients had clinically significant cancers and underwent completion thyroidectomy. FS had a sensitivity and positive predictive value of 22% and 40%, respectively, in identifying clinically significant thyroid cancer. Cost of thyroid lobectomy at varying rates of same-day discharge favored thyroid lobectomy without FS but with expedited pathology for all scenarios.

CONCLUSION

At our institution, there appears to be limited utility of FS at the time of thyroid lobectomy given the low predictive value for diagnosing a clinically significant thyroid cancer. In patients who are admitted overnight, expedited pathology is slightly less costly and may improve patient quality-of-life and decrease costs by avoiding delayed completion thyroidectomy. Overnight pathology for patients who undergo thyroid lobectomy may achieve modest cost-savings depending on institutional FS results and rates of malignancy.

Cytomorphologic features in thyroid nodules read as "suspicious for malignancy" on cytology may predict thyroid cancers with the BRAF mutation

Some morphologic parameters have been studied to help predict the BRAF(V600E) mutation using cytopathologic specimens, which can indicate which nodules should undergo further testing. The aim of this study was to investigate the value of cytomorphologic parameters to predict the BRAF(V600E) mutation in nodules read as "suspicious for malignancy" on cytology. This study included 142 resected nodules which were diagnosed as "suspicious for malignancy" on cytology in 142 patients. At our institution, BRAF(V600E) mutation analysis was performed at the request of the referring clinicians based on the clinical features of the patients, or the judgment of the radiologists performing US-FNA because suspicious US features were observed on the targeted nodule during this study period. Cytology smears were re-reviewed to assess the presence and amount of polygonal eosinophilic (plump) cells and microfollicles, and the presence of intranuclear pseudoinclusions, irregular nuclear membranes, nuclear grooves, sickles cells, psammoma bodies, and cystic changes. We evaluated the diagnostic performances of the cytomorphologic features to predict the BRAF(V600E) mutation. Polygonal eosinophilic (plump) cells, microfollicles, intranuclear pseudoinclusions, sickle cells, and cystic changes were significantly associated with the BRAF(V600E) mutation. The mutation was not present in all 6 thyroid nodules with microfollicles larger than 20% on cytology. Additionally, polygonal eosinophilic (plump) cells larger than 20%, cystic changes, and sickle cells on cytology had a high specificity of 95%, 96.7%, and 81.7%, respectively. Excluding 6 nodules with microfollicles larger than 20% on cytology, there were 82 (60.3%) nodules with the BRAF(V600E) mutation among the 136 nodules. Among the 136 nodules, there were 95 nodules with polygonal eosinophilic (plump) cells larger than 20%, cystic changes, or sickle cells on cytology. Of the 95 nodules, 69 (72.6%) had the mutation. Cytomorphologic features can help select nodules for the BRAF(V600E) mutation test among nodules read as "suspicious for malignancy" on cytology.

Thyroglossal duct remnant carcinoma: beyond the Sistrunk procedure

Thyroglossal duct remnants (TGDRs) account for more than 70% of anterior neck masses in children and 7% in adults; however, cancer is identified in only 1-2% of the cases. The diagnosis of a TGDR is based on clinical manifestation of a painless, anterior neck swelling, which elevates with swallowing. Cytological evaluation with fine needle aspiration and biopsy (FNAB) may facilitate the pre-operative diagnosis of malignancy, as the majority of TGDR cancers are of papillary histotype. The recommended treatment for symptomatic TGDR without evidence of malignancy is a Sistrunk procedure, which entails en bloc resection of the remnant and the mid-portion of the hyoid bone. The optimal management of patients with diagnosed malignancy is controversial, and in the past, additional total thyroidectomy was recommended for all of these patients. The purpose of this study is to review the literature on TGDR carcinomas, present the evidence on the available diagnostic tools, identify the surgical and post-operative medical management strategies, discuss current controversies, and conclude with a management algorithm.

Clinical implications of preoperative thyrotropin serum concentrations in patients who underwent thyroidectomy for nonfunctioning nodule(s)

Purpose

Thyroid stimulating hormone (TSH) measurement is the most sensitive screening test for thyroid dysfunction. TSH is a well-known thyroid growth factor but its pathogenic role in thyroid oncogenesis remains to be clarified. The purpose of the present study was to evaluate the relationship between clinicopathologic characteristics of nonfunctioning thyroid nodules and preoperative TSH serum concentrations.

Methods

Serum TSH concentrations can be affected by many factors. After exclusion of these confounding factors, a total of 126 patients who underwent thyroidectomy from Januray 2009 to December 2010 were included in this study. Average age was 45.4 ± 10.6 years and male:female ratio was 1:2.9. There were 11 patients with benign nodules, 34 patients with papillary thyroid microcarcinoma (PTMC) of less than 5 mm in maximal diameter, 66 patients with PTMCs of more than 5 mm but not more than 10 mm in maximal diameter, and 15 patients with papillary thyroid carcinoma (PTC) of more than 10 mm in maximal diameter.

Results

TNM stages of PTCs correlated with higher preoperative TSH serum concentrations. There were trends of higher preoperative TSH serum concentrations in patients who had extrathyroidal extension (P = 0.059) and advanced N stages (P = 0.120) but did not reach statistical significance. Patients' age, sex, and tumor volume did not seem to affect preoperative TSH serum concentrations significantly.

Conclusion

In patients who have PTCs without clinical, immunological, or ultrasonographic evidence of thyroiditis, higher preoperative TSH serum concentrations within the normal range might suggest advanced TNM stages.

Thyroid nodule fine-needle aspiration

Thyroid nodules are a common clinical problem and are noted much more commonly on imaging examinations than are apparent by palpation. Fine-needle aspiration biopsy (FNA), which yields a cytology specimen for analysis, is the standard test to determine whether surgical removal of a detected nodule is recommended. This article will review the current guidelines for recommending FNA of thyroid nodules, the technique and risk of the procedure, and the implications for patient care based on FNA results. FNA has an essential role in the evaluation of patients with thyroid nodules to reduce the rate of unnecessary thyroid surgery for patients with benign nodules and triage patients with thyroid cancer to appropriate surgery. Before the routine use of FNA, approximately 14% of resected thyroid nodules were malignant, whereas with the current widespread use of thyroid nodule FNA, >50% of resected thyroid nodules are malignant. Historically, thyroid nodules were identified by physical examination of the neck, with a prevalence of approximately 5%-10% of adults in the United States, and these patients underwent palpation-guided FNA in the physician's office. In recent years, the increased use of sonography to examine the thyroid as well as cross-sectional imaging of the neck by computed tomography and magnetic resonance imaging has resulted in the detection of many nonpalpable nodules. In older adults, thyroid nodules may be detected in >67% of people screened by sonography. Fortunately, the vast majority of nodules are benign, but when they are discovered, an assessment regarding the need to exclude malignancy using FNA must be performed.

A morpho-molecular diagnosis of papillary thyroid carcinoma: BRAF V600E detection as an important tool in preoperative evaluation of fine-needle aspirates

BACKGROUND

Although most thyroid nodule fine-needle aspiration (FNA) diagnoses are definitive or nearly definitive, about 30% of them are not read as definitively benign or malignant, the so-called indeterminate or suspicious FNA diagnosis. The prevalence of malignancy in FNA samples with these diagnoses varies from 10% to 52%. The first aim of this study was to determine if BRAF V600E analysis of thyroid FNA cytological smears could be performed with a relatively simple protocol. We also sought to determine if assessing the presence of BRAF gene mutations in preoperative FNA cytology slides would provide diagnostic information for FNA samples with a reading of indeterminate or suspicious thyroid lesions.

METHODS

DNA was extracted directly from FNA-stained smears of 111 patients with thyroid lesions having different cytological diagnoses. There was 1 cystic nodule, 20 microfollicular proliferations without atypia, 32 that were suspicious for papillary carcinoma, 56 papillary thyroid carcinomas (PTC), and 2 poorly differentiated carcinomas. The BRAF V600E mutational status was determined by sequencing analysis in all patients. The histopathological diagnosis was obtained in all cases.

RESULTS

We observed that 56/90 (62.3%) patients received a definitive diagnosis of PTC when only cytology was used. After molecular analysis, the BRAF V600E mutation was detected in 18/32 (56.2%) cases with a cytology of suspicious for papillary carcinoma and 41/56 (73.2%) with PTC. According to the morpho-molecular analysis (i.e., traditional cytology combined with BRAF V600E analysis) 74/90 (82.2%) patients could be assigned a definitive diagnosis of PTC. Therefore, the addition of molecular analysis yielded an increase of 20% in the sensitivity compared to cytology alone.

CONCLUSIONS

The method of molecular analysis of thyroid FNA smears described here can be easily performed after the FNA, thereby avoiding inconvenience and additional time during the FNA and permitting later analysis of samples having indeterminate cytology features. The increased sensitivity of this preoperative morpho-molecular analysis should provide information that is useful in deciding the extent of thyroid surgery for thyroid nodules that are indeterminate or suspicious on cytology.

The role of BRAFV600E mutation and ultrasonography for the surgical management of a thyroid nodule suspicious for papillary thyroid carcinoma on cytology

BACKGROUND

This study was designed to investigate the role of BRAFV600E mutation status in cytology specimens and ultrasonography (US) when planning surgery for thyroid nodules with cytologic results suspicious for papillary thyroid carcinoma (PTC).

METHODS

From July 2008 to November 2008, 91 consecutive patients with cytologic results of suspicious for PTC underwent thyroidectomy. Before surgery, all patients received US-guided fine needle aspiration biopsy (US-FNAB) solely for the purpose of BRAFV600E mutation analysis of thyroid nodules suspicious for PTC on cytology. BRAFV600E mutations were tested by direct sequencing. We investigated the role of BRAFV600E mutation and US in planning the thyroid surgery.

RESULTS

Of 91 nodules suspicious for PTC, 42 (46.2%) were positive for the BRAFV600E mutation and confirmed to be PTC by histopathology. The positive predictive values of BRAFV600E mutation was 100%. Of the 49 nodules without the BRAFV600E mutation, 42 (85.7%) proved to be PTC. Thirty-nine of 42 (92.9%) PTCs were suspicious for malignant features on US. Two of seven (28.6%) benign lesions showed probably benign features. The sensitivity, positive predictive value, and accuracy of US in thyroid nodules without BRAFV600E mutations was 92.9% (39/42), 88.6% (39/44), and 83.7% (41/49), respectively.

CONCLUSIONS

The BRAFV600E mutation is a useful molecular marker for preoperative diagnosis of PTC and an indicator for therapeutic thyroid surgery in the nodule with cytologic results suspicious for PTC. In thyroid nodules without the BRAFV600E mutation, suspicious malignant features on US may help in planning the extent of thyroid surgery.

Contemporary management of papillary carcinoma of the thyroid gland

The incidence of thyroid cancer is increasing by 4% per year. Thyroid cancer has become the eighth most common malignancy diagnosed in women. Papillary cancer accounts for 80% of all thyroid cancer. The management of papillary thyroid cancer is challenging, primarily because there have been no prospective randomized trials to help guide therapeutic decision making. The purpose of this article is to discuss the contemporary management of papillary thyroid cancer, including the diagnosis and pre-operative evaluation, surgical management, postoperative thyroid hormone and radioiodine therapy, long-term follow-up, prognosis and management of recurrent and metastatic disease. The role of molecular markers to enhance the cytological diagnosis of papillary cancer and new molecular-based therapies will also be reviewed.

Higher serum thyroid stimulating hormone level in thyroid nodule patients is associated with greater risks of differentiated thyroid cancer and advanced tumor stage

CONTEXT

TSH is a known thyroid growth factor, but the pathogenic role of TSH in thyroid oncogenesis is unclear.

OBJECTIVE

The aim was to examine the relationship between preoperative TSH and differentiated thyroid cancer (DTC).

DESIGN

The design was a retrospective cohort.

SETTING, PARTICIPANTS

Between May 1994 and January 2007, 1198 patients underwent thyroid surgery at a single hospital. Data from the 843 patients with preoperative serum TSH concentration were recorded.

MAIN OUTCOME MEASURES

Serum TSH concentration was measured with a sensitive assay. Diagnoses of DTC vs. benign thyroid disease were based on surgical pathology reports.

RESULTS

Twenty-nine percent of patients (241 of 843) had DTC on final pathology. On both univariate and multivariable analyses, risk of malignancy correlated with higher TSH level (P=0.007). The likelihood of malignancy was 16% (nine of 55) when TSH was less than 0.06 mIU/liter vs. 52% (15 of 29) when 5.00 mIU/liter or greater (P=0.001). When TSH was between 0.40 and 1.39 mIU/liter, the likelihood of malignancy was 25% (85 of 347) vs. 35% (109 of 308) when TSH was between 1.40 and 4.99 mIU/liter (P=0.002). The mean TSH was 4.9+/-1.5 mIU/liter in patients with stage III/IV disease vs. 2.1+/-0.2 mIU/liter in patients with stage I/II disease (P=0.002).

CONCLUSIONS

The likelihood of thyroid cancer increases with higher serum TSH concentration. Even within normal TSH ranges, a TSH level above the population mean is associated with significantly greater likelihood of thyroid cancer than a TSH below the mean. Shown for the first time, higher TSH level is associated with advanced stage DTC.