Fine-needle aspiration optimizes surgical management in patients with thyroid cancer

Colorectal cancer metastases in thyroid: case report and literature review

BACKGROUND

The thyroid gland is an uncommon site for metastatic deposits from non-thyroid malignancies, occurring in only 1.4 - 3% of surgical specimens where malignancy is suspected. It is even rarer for the source of thyroid metastases to be of colorectal origin. In most cases reported, colorectal metastases in the thyroid occurs many years later after the primary colorectal cancer has been diagnosed and treated. In this unique case, a primary sigmoid carcinoma metastasised to the thyroid gland and presented synchronously as a thyroid nodule.

CASE PRESENTATION

We describe a case of a 64-year-old Caucasian woman who presented with clinical features of metastatic cancer of unknown origin. Her medical history included underlying hyperthyroidism. She had a large pelvic mass adjacent to the sigmoid colon, a left lower lobe lung mass and a suspicious nodule in the left thyroid lobe. A fine-needle aspiration biopsy of the thyroid nodule was performed, which remarkably showed malignant cells originating from primary colorectal cancer on immunohistochemical staining. The patient was managed with palliative chemotherapy given the poor prognosis due to disseminated colorectal malignancy.

CONCLUSIONS

Colorectal adenocarcinoma metastases can rarely present as a metastatic thyroid nodule. Fine-needle aspiration should be performed in suspicious thyroid nodules and may be the least invasive way of identifying a metastatic colorectal or other non-thyroidal malignancy in patients presenting with an unknown primary. The pathologist should be vigilant to this possibility and specific immunohistochemical markers should be used to ensure accurate diagnosis. In thyroid metastases, the prognosis is ultimately determined by the primary tumour but thyroidectomy still has a role in alleviating compressive symptoms and can potentially improve survival in selected cases.

Performing Calcitonin Immunocytochemistry on an Additional ThinPrep Slide in Fine-Needle Aspiration Diagnosis of Medullary Thyroid Carcinoma

OBJECTIVES

This study reviewed the institutional experience of performing calcitonin immunostain on an additional ThinPrep slide in fine-needle aspiration (FNA) diagnosis of medullary thyroid carcinoma (MTC).

METHODS

Thyroid FNA cases with MTC suspected or included in the differential diagnosis during cytologic evaluation and calcitonin immunostain performed were retrieved and reviewed.

RESULTS

Calcitonin immunostain was performed in 132 cases with 41 positive, 81 negative, and 10 indeterminate results. All calcitonin-positive cases had a cytologic diagnosis of MTC while all calcitonin-negative cases were cytologically classified as non-MTCs except for two cases suspicious for MTC. In 10 cases with an indeterminate calcitonin result, diagnoses of non-MTC and suspicious for MTC were rendered in 6 and 4 cases, respectively. Histopathologic follow-up was available in 85 (64%) cases. All cytologically diagnosed MTC cases were confirmed on histopathology. In 3 MTC cases with an indeterminate calcitonin result, 1 case was misclassified cytologically as follicular neoplasm. The calculated sensitivity, specificity, positive predictive value, and negative predictive value of calcitonin immunostain were all 100% for diagnosing MTC.

CONCLUSIONS

Our study demonstrates the feasibility of performing calcitonin immunostain on an additional ThinPrep slide. Calcitonin immunocytochemistry is a valuable adjunct test for FNA diagnosis and differential diagnosis of MTC.

2021 American Thyroid Association Guidelines for Management of Patients with Anaplastic Thyroid Cancer

Background: Anaplastic thyroid cancer (ATC) is a rare but highly lethal form of thyroid cancer. Since the guidelines for the management of ATC by the American Thyroid Association were first published in 2012, significant clinical and scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, and researchers on published evidence relating to the diagnosis and management of ATC. Methods: The specific clinical questions and topics addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of the Task Force members (authors of the guideline). Relevant literature was reviewed, including serial PubMed searches supplemented with additional articles. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations. Results: The guidelines include the diagnosis, initial evaluation, establishment of treatment goals, approaches to locoregional disease (surgery, radiotherapy, targeted/systemic therapy, supportive care during active therapy), approaches to advanced/metastatic disease, palliative care options, surveillance and long-term monitoring, and ethical issues, including end of life. The guidelines include 31 recommendations and 16 good practice statements. Conclusions: We have developed evidence-based recommendations to inform clinical decision-making in the management of ATC. While all care must be individualized, such recommendations provide, in our opinion, optimal care paradigms for patients with ATC.

Promoter Methylation of Four Tumor Suppressor Genes in Human Papillary Thyroid Carcinoma

BACKGROUND & OBJECTIVE

Papillary thyroid cancer (PTC) is considered to be the most common type of thyroid malignancies. Epigenetic alteration, in which the chromatin conformation and gene expression change without changing the sequence of DNA, can occur in some tumor suppressor genes and oncogenes. Methylation is the most common type of epigenetic alterations that can be an excellent indicator of PTC invasive behavior.

METHODS

In this research, we determined the promoter methylation status of four tumor suppressor genes (SLC5A8, RASSF1, MGMT, and DNMT1) and compared the results of 55 PTC cases with 40 goiter patients. For methylation, we used the methylation-sensitive high resolution melting (MS-HRM) assay technique. The resulting graphs of each run were compared with those of 0%, 50%, and 100% methylated controls.

RESULTS

Our data showed that the promoter methylation of SLC5A8, Ras association domain family member 1(RASSF1), and MGMT were significantly different between PTC tissue and goiter with P-value less than 0.05. The most significant differences were observed in RASSF1; 77.2% of hyper-methylated PTC patients versus 15.6% hyper-methylated goiter samples (P<0.001).

CONCLUSION

RASSF1 promoter methylation can be a PTC genetic marker. RASSF1 promoter methylation is under the impact of the methyltransferase genes (DNMT1 and MGMT), protein expression, and promoter methylation.

Fine-Needle Aspiration Versus Frozen Section in the Evaluation of Malignant Thyroid Nodules in Patients With the Diagnosis of Suspicious for Malignancy or Malignancy by Fine-Needle Aspiration

Context.—

The Bethesda System for Reporting Thyroid Cytopathology recommends against the use of intraoperative frozen section (FS) during lobectomy of a thyroid nodule with a fine-needle aspiration (FNA) diagnosis of malignant. Bethesda recommendations for FS in the FNA category of suspicious for malignancy (SFM) is less well-defined. In some institutions in China, FS examination is performed during lobectomy even for FNA-proven malignant cases.

Objective.—

—To compare the efficacy of FNA versus FS in the evaluation of malignant thyroid lesions.

Design.—

A 3-year retrospective analysis from a single institution was performed on cases with an FNA diagnosis of SFM or malignant with subsequent FS examination during thyroidectomy. The results of FNA and FS findings were compared to the final thyroidectomy pathology.

Results.—

—A total of 5832 thyroidectomy procedures were performed: 1265 cases had FNA and FS results available. Fine-needle aspiration gave a diagnosis of SFM to 306 cases and a diagnosis of malignant to 821 cases. Of the SFM cases, 10.5% (32 of 306) had benign/indeterminate, 4.6% (14 of 306) suspicious, and 84.9% (260 of 306) malignant FS results. Final pathology showed 56.3% (18 of 32), 64.3% (9 of 14), and 100% (260 of 260) malignancy rates, respectively. For the malignant FNA group, 10.0% (82 of 821) had benign/indeterminate, 4.4% (36 of 821) suspicious, and 85.6% (703 of 821) malignant FS results. The final pathology showed 96.4% (79 of 82), 97.2% (35 of 36), and 99.9% (702 of 703) malignancy rates, respectively.

Conclusions.—

Frozen section should not be performed for the malignant FNA category because FS evaluation may result in 10% falsely negative findings. Performing FS for SFM may be better justified; however, more than half of FS cases read as benign in this category had malignant final pathology. Therefore, caution should be taken for FS results even in the SFM group.

Morphometric Analysis of Thyroid Follicular Cells with Atypia of Undetermined Significance

BACKGROUND

Atypia of undetermined significance (AUS) is a category that encompasses a heterogeneous group of thyroid aspiration cytology. It has been reclassified into two subgroups based on the cytomorphologic features: AUS with cytologic atypia and AUS with architectural atypia. The nuclear characteristics of AUS with cytologic atypia need to be clarified by comparing to those observed in Hashimoto thyroiditis and benign follicular lesions.

METHODS

We selected 84 cases of AUS with histologic follow-up, 24 cases of Hashimoto thyroiditis, and 26 cases of benign follicular lesions. We also subcategorized the AUS group according to the follow-up biopsy results into a papillary carcinoma group and a nodular hyperplasia group. The differences in morphometric parameters, including the nuclear areas and perimeters, were compared between these groups.

RESULTS

The AUS group had significantly smaller nuclear areas than the Hashimoto thyroiditis group, but the nuclear perimeters were not statistically different. The AUS group also had significantly smaller nuclear areas than the benign follicular lesion group; however, the AUS group had significantly longer nuclear perimeters. The nuclear areas in the papillary carcinoma group were significantly smaller than those in the nodular hyperplasia group; however, the nuclear perimeters were not statistically different.

CONCLUSIONS

We found the AUS group to be a heterogeneous entity, including histologic follow-up diagnoses of papillary carcinoma and nodular hyperplasia. The AUS group showed significantly greater nuclear irregularities than the other two groups. Utilizing these features, nuclear morphometry could lead to improvements in the accuracy of the subjective diagnoses made with thyroid aspiration cytology.

Malignancy risk and false-negative rate of fine needle aspiration cytology in thyroid nodules ≥4.0 cm

BACKGROUND

We aimed to evaluate malignancy rate and to determine false negativity of fine needle aspiration biopsy (FNAB) in thyroid nodules ≥4.0 cm.

METHODS

The medical records of patients who underwent thyroidectomy between January 2007 and December 2014 were reviewed. Demographic and clinical data as well as preoperative ultrasonography findings were analyzed. The nodules in these patients were grouped as ≥4.0 cm and <4.0 cm according to ultrasonography measurements. Nodules <4.0 cm were further divided into 1.0-3.9 cm and <1.0 cm. Histopathologically malignant nodules with preoperative benign cytology were defined as having false-negative FNAB.

RESULTS

There were 1,008 nodules that measured ≥4.0 cm, 4,013 nodules that measured 1.0-3.9 cm, and 540 that measured nodules <1.0 cm. Based on histopathologic findings, 8.5%, 10.2%, and 25.6% of nodules ≥4.0 cm, 1.0-3.9 cm, and <1.0 cm were malignant, respectively (P < .001). There was no significant difference between 1.0-3.9-cm and ≥4.0-cm nodules with respect to malignancy (P = .108). False-negativity rates were 4.7% in nodules ≥4.0 cm, 2.2% in nodules measuring 1.0-3.9 cm, and 4.8% in <1.0-cm nodules. Nodules measuring <1.0 cm and ≥4.0 cm had similar false-negativity rates (P = .93), while 1.0-3.9-cm nodules had statistically lower false-negativity rates than those found in the other two groups (P = .03 and P < .001, respectively).

CONCLUSION

Of the nodules that were operatively excised, nodules ≥4.0 cm had a similar risk of malignancy as nodules 1.0-3.9 cm. The rate of false-negative FNAB in nodules ≥4.0 cm was twice as high as in nodules 1.0-3.9 cm; however, we do not think it is high enough to recommend a routine operation when cytology results are benign.

The diagnostic accuracy of ultrasound-guided fine-needle aspiration biopsy for thyroid nodules three centimeters or larger in size

BACKGROUND AND PURPOSE

Whether under ultrasonography (US) guidance or not, fine-needle aspiration biopsy (FNAB) has some limitations, particularly in larger nodules. In this study, we aimed to evaluate the diagnostic value of US-guided fine-needle aspiration biopsy (US-FNAB) in thyroid nodules equal to or larger than 3 cm.

MATERIALS AND METHODS

Data of 267 patients operated for nodular goiter in the period of January 2006 and March 2012 were reviewed retrospectively. The study group (40 males, 104 females; mean age 42.3 ± 12.3, between 17 and 71) consisted of patients with nodules with a diameter of 3 cm or larger. Patients with nodules less than 3 cm in diameter were considered as the control group (27 males, 96 females; mean age 44.4 ± 11.9, between 18 and 71).

RESULTS

For nodules smaller than 3 cm, US-FNAB had an accuracy rate of 60% and a false negativity rate of 21.9%. In nodules equal to or larger than 3 cm, the accuracy rate of US-FNAB was 80%, with a false negativity rate of 6.7%. Malignancy was observed in 16% of the study group and 42.3% of the control group.

CONCLUSION

This study showed that increased nodule diameter is not associated with limitations in the diagnostic value of US-FNAB. We also found that the malignancy rate was smaller for larger nodules. This finding reflects the importance of accurate and rational diagnostic work-up and clinical management for detecting malignancy and surgical decision-making.

Anaplastic thyroid cancer: ultrasonographic findings and the role of ultrasonography-guided fine needle aspiration biopsy

PURPOSE

To investigate the ultrasonographic (US) features of anaplastic thyroid cancer (ATC) and the diagnostic performance of US-guided fine needle aspiration biopsy (FNAB) therein.

MATERIALS AND METHODS

Eighteen cases of ATC diagnosed between January 2001 and May 2011 were included. FNAB was performed in all cases. Initial FNAB results were divided into three groups: 1) the cytological ATC group, cytological diagnosis of ATC; 2) the underestimated group, cytological diagnoses of malignancy other than ATC; and 3) the false negative group, cytological diagnoses of atypical, benign and non-diagnostic lesions. We retrospectively reviewed US findings and compared treatment modalities between each group.

RESULTS

Among the 18 patients, there were nine in the initially cytological ATC group, four in the underestimated group and five in the false negative group. The most common US features of ATC were a solid (64.7%) and irregular shaped (88.2%) mass with lymph node involvement (76.4%). However, except for lymph node involvement (p=0.003), US findings for each group were not statistically different. The initial cytological diagnostic accuracy of ATC was 50% (9/18). Surgery was performed less in the ATC group (11%) and the false negative group (20%) than the underestimated group (75%).

CONCLUSION

The US features of ATC were not especially different from other types of aggressive thyroid cancer. A correct diagnosis of ATC by initial US-FNAB was made in 50% of the patients, which is significant in that therapeutic surgery can be undertaken in lower numbers if correctly diagnosed.

Survival and failure outcomes in primary thyroid lymphomas: a single centre experience of combined modality approach

Primary thyroid lymphoma (PTL) is a rare malignancy and represents 2%–5% of all thyroid malignancies and 1%–2.5% of all malignant lymphomas. We present our institute's experience in combined modality management of 16 successive patients of PTL treated from 2005 to 2010. The median age of the patients was 56.0 years. Five patients were males, and 11 patients were females. An enlarging thyroid mass was the most common presenting symptom. 14 patients had diffuse large B-cell lymphoma, and 2 patients had follicular lymphoma. The most common stage of presentation was stage II comprising 6 (37.5%) patients. All patients received CCT, and only 12 patients received involved field RT with a median dose of 36.0 Gy. 10 patients (62.5%) had CR, and 6 patients (27.5%) had PR. Eight patients had disease progression in subsequent followup and this included the initial 6 patients with PR. The 5-year DFS was 40.0%, and median DFS was 47 months. The 5-year OS was 41.0%, and median OS was 51 months. Most common presentation in our series was locally advanced tumors. Most of these patients require combined modality management. Risk-adapted and multimodality approach is the need of the hour to achieve good control rates while minimizing treatment related toxicity.

Radioactive iodine scanning is not beneficial but its use persists for euthyroid patients

BACKGROUND

Radioactive iodine (RAI) scanning is a method of determining the functional status of thyroid nodules. Historically, practitioners thought "cold" or inactive nodules were more likely malignant. However, surgeons no longer find these scans helpful for preoperative management of euthyroid patients. The purpose of this study was to evaluate the utility of RAI scans.

METHODS

We retrospectively reviewed cases of euthyroid patients (thyroid-stimulating hormone > 1.0 mIU/L) who underwent RAI scans before thyroid surgery at our institution between 1994 and 2011. We correlated the RAI scan results with final pathology. We considered RAI scans concordant with pathology when we found a malignancy on the same lobe as a cold nodule. We also tabulated the specialty and affiliation of the ordering physicians.

RESULTS

A total of 109 euthyroid patients underwent RAI scanning as part of their preoperative workup. Of these, 88 patients (81%) had a cold nodule. A malignancy concordant with the RAI scan findings occurred in only 15 of these patients (17%). Non-surgical specialties ordered 90 scans (95%). Only 11 of these scans (10%) were performed in the past 5 y, and physicians outside the academic institution ordered all 11 (100%) of these. A linear regression of RAI scanning per year yielded a slightly negative slope (m-0.32 per year).

CONCLUSIONS

Radioactive iodine scanning is not useful for the surgical management of thyroid disease in euthyroid patients because it poorly predicts malignancy. The overall use of RAI scans is trending downward, but they are still ordered by non-surgical referring physicians.

In patients with thyroid cancer of follicular cell origin, a family history of nonmedullary thyroid cancer in one first-degree relative is associated with more aggressive disease

BACKGROUND

About 5% of nonmedullary thyroid cancers (NMTCs) are familial. Most patients with a family history of thyroid cancer do not meet the definition of familial NMTC (FNMTC; two or more affected family members). The aim of this study was to determine whether patients with a family history of NMTC, but who do not meet the definition of FNMTC, have more aggressive disease.

METHODS

A database of 1502 thyroidectomies was reviewed and 358 patients with NMTC who did not have a family history of benign thyroid disease and who underwent thyroidectomy from January 1994 to December 2008 were identified. These included 324 (90%) patients with papillary thyroid carcinoma (PTC), 24 (7%) with follicular thyroid cancer, and 10 (3%) with anaplastic or Hürthle cell carcinoma. Among them, those with and without a family history of NMTC in first-degree relatives were compared. Then patients with only one affected family member were compared with FNMTC patients.

RESULTS

Thirty-seven (10%) patients had a family history of thyroid cancer, all to of which had PTC. Patients with a family history of NMTC had a similar tumor size than those without (2±0 vs. 2.1±0 cm, p=0.72) but they were significantly younger (43±3 vs. 49±1 years, p=0.04), and more likely to have multicentricity (48% vs. 22%, p=0.01), malignant lymph nodes (22% vs. 11%, p=0.02), and local invasion to surrounding tissues (5.4% vs. 0.6%, p=0.007). They also had a higher recurrence rate (24% vs. 12%, p=0.03) than patients without a family history. Interestingly, patients with only one affected family member were similar to FNMTC patients with respect to age (44±4 vs. 40±3 years, p=0.4), tumor size (2±0 vs. 1.9±0 cm, p=0.65), rate of multicentricity (44% vs. 52%, p=0.57), malignant lymph nodes (22% vs. 21%, p=0.93), local invasiveness (5.5% vs. 11%, p=0.59), and disease recurrence (28% vs. 21%, p=0.56).

CONCLUSION

Patients with NMTC having a family history of thyroid cancer have more aggressive disease, regardless of whether they meet the current definition of FNMTC regarding number of affected family members. Therefore, any positive family history should be considered a risk factor for more aggressive thyroid carcinoma.

Second opinion in thyroid fine-needle aspiration biopsy by the Bethesda system

The present study was designed to determine the impact of secondary review of thyroid fine-needle aspiration (FNA) biopsy on surgical management. A retrospective review of patients referred to our institution with a thyroid FNA biopsy was conducted. Cytologic diagnoses from the report at our center and the referring institution were re-categorized by the Bethesda System for Reporting Thyroid Cytopathology. The rate of diagnostic disagreement was evaluated between Primary Diagnosis (PD) and Second Opinion Diagnosis (SOD), and the clinicopathologic correlations and the number of cases that prompted changes in treatment as a result of diagnostic disagreement were analyzed. 1499 patients meeting our study criteria were enrolled in this study. Diagnostic disagreement comprised 394 cases (26.3%). In the case of diagnostic disagreement, SOD was supported on clinicopathologic follow-up in 271 cases (68.8%), of which a change in management was made in 54 (13.7%) cases, and PD was supported in 93 (23.6%) cases, of which a change in management was made in 13 (3.3%) cases. By the second opinion, 65 (4.5%) patients received proper management, and 14 (1.0%) patients received superfluous management. Wide use of secondary cytopathologic review of thyroid FNA specimens from referring institutions was recommended.

Fine needle aspiration of the thyroid: a contemporary experience of 3981 cases

BACKGROUND

Fine needle aspiration (FNA) is an essential tool for the management of thyroid nodules. Recently, several national organizations have recommended FNA of all thyroid nodules >1 cm. With the increase use of imaging in the practice of medicine over the last decade, the number of incidentally discovered thyroid nodules is rising. Therefore, we analyzed our experience to determine if these changes in practice led to alterations in the population of patients undergoing FNA at our institution.

MATERIALS AND METHODS

Data were collected from 981 consecutive patients who underwent thyroid FNA at our institution between 2002 and 2009. Patients were divided in two groups: the early time period 2002-2005 (group 1) and later time period 2006-2009 (group 2). Data from the two groups were analyzed with t-test and χ(2) tests (SPSS, Inc., Chicago, IL).

RESULTS

Comparing the groups, the number of FNAs performed in the later time period increased significantly by 250%. Patients in the later time period (group 2) were more likely to be female and were significantly older. With regard to FNA diagnoses, the number of benign FNAs increased, while the percentage of FNAs diagnosed as malignant and as follicular neoplasm decreased. There also appears to be an increase in the incidence of thyroiditis.

CONCLUSIONS

The use of thyroid FNA has markedly increased during this contemporary series. This rise in thyroid FNA appears to be due to biopsy of benign thyroid nodules. With time, more females and older patients have undergone FNA, possibly reflecting the increased use of imaging studies in this patient population.

Fine-needle aspiration of follicular patterned lesions of the thyroid: Diagnosis, management, and follow-up according to National Cancer Institute (NCI) recommendations

The National Cancer Institute (NCI) State of the Science Conference on thyroid fine-needle aspiration (FNA) proposed that follicular patterned lesions can be divided into two diagnostic categories; follicular lesion of undetermined significance/Atypia of undetermined significance (FLUS/AUS) and suspicious for follicular neoplasm/follicular neoplasm (SFON/FON). The former group can benefit from repeat FNA (RFNA) to achieve a more definitive diagnosis and the latter should undergo surgical excision for histologic characterization (adenoma vs. carcinoma). In this study, we report the combined experience from our institutions with thyroid FNA cases that can be placed into NCI-designated thyroid FNA diagnostic categories for follicular patterned lesions.The case cohort comprised of 857 cases in 645 females and 212 males; 509 cases could be classified as FLUS/AUS and 348 as SFON/FON. Histologic follow-up was available in 273/509 (54%) cases diagnosed as FLUS/AUS and 251/348 (72%) cases diagnosed as SFON/FON.RFNA was performed in 203/509 (40%) patients classified as FLUS/AUS. RFNA diagnoses were: benign (125 cases), FLUS (46 cases), SFON/FON (20 cases), suspicious for papillary carcinoma (7 cases), papillary carcinoma (3 cases) and non-diagnostic (2 cases). The malignancy rate on surgical excision in the FLUS/AUS group was 27 and 15% with and without RFNA, respectively; and 25% in cases diagnosed as SFON/FON.RFNA is effective in managing thyroid nodules diagnosed as FLUS/AUS since the malignancy rates are different in cases with or without RFNA (27% vs. 15%). The malignancy rate (25%) in cases diagnosed as SFON/FON is similar to reported by other authors.

A systematic review of cases reporting needle tract seeding following thyroid fine needle biopsy

BACKGROUND

Because of its accuracy and cost-effectiveness, thyroid fine needle biopsy (FNB) is the procedure of choice in the preoperative management of thyroid nodules. Needle tract seeding (NTS) has been a concern since the earliest days of FNB, contributing to the delayed acceptance of FNB as a safe procedure. In this review we tried to systematically record all reports of NTS after diagnostic thyroid FNB and provide useful hints to minimize the risk of NTS.

METHODS

Computerized advanced search for primary evidence was performed in the PubMed (Public/Publisher Medline) electronic database. The search was not limited by publication time or English language.

RESULTS

Ten relevant articles were found: eight case reports, one case in a surgical series, and one retrospective observational study.

CONCLUSIONS

Despite initial concerns about the risk of NTS, FNB is now considered to be a safe procedure. Although proper FNB technique can reduce its risk, NTS is an unavoidable complication of FNB, which clinicians should be aware of. However, the incidence of NTS is low and it doesn't seem to affect the prognosis because the seedings can be surgically removed without recurrence. The management of the thyroid nodules is to-date based on FNB, and the benefits from FNB (elimination of needless imaging and surgery) far outweigh the potential risk for NTS.

Thyroid fine-needle aspiration with atypia of undetermined significance: a necessary or optional category?

BACKGROUND

Atypia of undetermined significance is a controversial category in thyroid fine-needle aspiration (FNA), not only for its questioned clinical utility, but also for its very existence as an expression of uncertainty. The current study was performed to investigate the potential impact of eliminating this category on the sensitivity and specificity for detecting thyroid neoplasms by FNA.

METHODS

Forty cases originally diagnosed as atypia of undetermined significance with histologic follow-up were selected for the present study. These cases were reinterpreted blindly by 2 experienced reviewers, who eliminated atypia of undetermined significance as a diagnostic possibility and reclassified these cases as either benign, follicular neoplasm, suspicious for malignancy, or malignant. Twenty-six cases of atypia of undetermined significance were randomly selected and reevaluated 6 months later to study intraobserver variation.

RESULTS

After eliminating the atypia of undetermined significance category, the sensitivity for detecting papillary thyroid carcinoma (PTC) was reduced from 100% to 27% (P = .04). In those atypia of undetermined significance cases that were reclassified as benign, 37% had PTC. In those reclassified as follicular neoplasm or suspicious for malignancy, 38% were histologically proven to be benign lesions. Unanimous interobserver and intraobserver agreement was observed in only 60% of cases.

CONCLUSIONS

Eliminating the diagnosis of atypia of undetermined significance substantially decreases the sensitivity of thyroid FNAs and increases both false-positive and false-negative rates. In addition, it increases interobserver and intraobserver variability. Therefore, the atypia of undetermined significance category should not be eliminated; but we advocate minimizing its use.

Clinical efficacy of fine-needle aspiration biopsy of thyroid nodules in males

BACKGROUND

It has recently been suggested that the use of fine-needle aspiration (FNA) biopsy of thyroid nodules in male patients is associated with an unacceptably high false-negative rate in the detection of thyroid malignancy. We hypothesize that FNA biopsy is an accurate preoperative tool for detecting thyroid cancer in men, and that false negative rates are significantly lower than recently reported.

MATERIALS AND METHODS

A retrospective database analysis was performed on all male patients who underwent thyroid surgery from May 1994 through January 2007 at a single institution. The results of preoperative FNA biopsies were compared with final surgical pathologic results. FNA biopsy results were reported as benign, malignant, inconclusive (i.e., follicular neoplasm), or nondiagnostic; final surgical pathology was reported as benign or malignant.

RESULTS

Of 1205 patients who underwent thyroidectomy, 273 (23%) were male. Preoperative FNA biopsy results were obtained in 60% of these male patients and were read as benign in 45/165 (27%) patients, malignant in 47/165 (28%) patients, inconclusive in 66/165 (40%) patients, and nondiagnostic in 7/165 (4%) patients. In male patients with cytology reported as benign, 3/45 (6.7%) FNAs were determined to be malignant on final pathology.

CONCLUSIONS

Our study determined that FNA biopsy of thyroid nodules in male patients has an acceptably low false-negative rate of 6.7% and is, therefore, an accurate and useful diagnostic tool. We recommend preoperative FNA biopsy for all male patients presenting with thyroid nodules as a standard of practice.

Accuracy of fine-needle aspiration biopsy for predicting neoplasm or carcinoma in thyroid nodules 4 cm or larger

HYPOTHESIS

All thyroid nodules 4 cm or larger should be surgically removed regardless of fine-needle aspiration biopsy (FNAB) results because of an unacceptably high rate of false-negative preoperative biopsy results in these large nodules.

DESIGN

Retrospective cohort study.

SETTING

Single-institution, tertiary academic referral center.

PATIENTS

A retrospective analysis was performed on all patients who underwent surgery for a thyroid nodule 4 cm or larger from May 1, 1994, through January 31, 2007.

MAIN OUTCOME MEASURES

Preoperative FNAB results were correlated with final surgical pathologic results. The FNAB results were reported as nondiagnostic, benign, inconclusive (follicular neoplasm), or malignant, whereas the final surgical pathologic data were reported as benign or malignant.

RESULTS

Of 155 patients who underwent a thyroidectomy for a nodule 4 cm or larger, 21 patients (13.5%) had a clinically significant thyroid carcinoma within the nodule on final pathologic analysis. Preoperative cytologic testing of the mass was performed on 97 patients, and the results read as benign for 52, inconclusive for 23, nondiagnostic for 11, and malignant for 11. In lesions 4 cm or larger, 26 of 52 FNAB results reported as benign (50.0%) turned out to be either neoplastic (22) or malignant (4) on final pathologic analysis. Among patients with nondiagnostic FNAB results, the risk of malignant neoplasms was 27.3%.

CONCLUSIONS

In patients with thyroid nodules 4 cm or larger, the FNAB results are highly inaccurate, misclassifying half of all patients with reportedly benign lesions. Furthermore, those patients with a nondiagnostic FNAB result display a high risk of differentiated thyroid carcinoma. Therefore, we recommend that diagnostic lobectomy be strongly considered in patients with thyroid nodules 4 cm or larger regardless of FNAB cytologic test results.

A diagnostic predictor model for indeterminate or suspicious thyroid FNA samples

BACKGROUND

The management of patients with thyroid fine-needle aspiration (FNA) specimens that are neither benign nor malignant still remains problematic. Efforts to improve their management have focused on identifying risk factors that predict malignancy. This study seeks to identify clinical and tumor characteristics that predict thyroid malignancy among patients with indeterminate or suspicious FNA and to develop a diagnostic predictor model.

METHODS

The records of 639 patients with an indeterminate or suspicious thyroid FNA between January 1995 and April 2005 were reviewed. Patient and tumor characteristics were evaluated for their potential to predict malignancy in the final surgical histopathology. A diagnostic predictor model was designed based on statistically significant predictors. Patients seen between April 2005 and April 2007 were used to validate the model.

RESULTS

Patient age, nodule size, and FNA cytopathology were identified as risk factors. Patients at extremes of age were at increased risk. Patients 50 years of age had the lowest risk of malignancy. For patients less than age 50, the risk increased 3% for each year decrease in age (p = 0.001). After 50, the risk increased 3.4% for each year increase in age (p = 0.016). Nodules 2.5 cm had the lowest likelihood of malignancy. For smaller nodules, the risk increased 53% per cm decrease in size (p < 0.001). For larger nodules, the risk increased 39% per cm increase (p < 0.001). Patients with FNA cytology suspicious for papillary thyroid carcinoma had the greatest risk of malignancy (p < 0.001).

CONCLUSIONS

A predictor model was created using the variables age, nodule size, and FNA cytology to predict thyroid malignancy.

Frozen section and fine needle aspiration biopsy in thyroid surgery - needles and sections

PURPOSE

To review our own experience with fine needle aspiration biopsy (FNAB) and frozen section (FS) in thyroid surgery and to assess the value of FNAB and FS in predicting malignancy in patient with thyroid disease.

METHODS

The records of 300 patients who underwent thyroid surgery between April 2001 and June 2006 were analyzed.

RESULTS

Of the 153 patients who had preoperative FNABs performed, 8 (5.22%) were reported as indeterminate, 100 (65.35%) were read as benign, and 3 (1.96%) were read as malignant. Fourty two of the FNABs were inadequate for evaluation (27.45%). When occult papillary carcinomas were excluded, sensitivity, and accuracy rates for FNAB reached 100%. One hundred and ninety one patients had FSs performed. 184 (96.33%) of these were reported as benign, 4 (2.09%)were reported as malignant, 3 (1.57%) were deferred to permanent paraffin (PP) sections. When occult papillary carcinomas were excluded, sensitivity, and accuracy rates for FS were 42.85%, 43%, and 97.28% respectively.

CONCLUSIONS

Our data supports the use of FNAB in the confirmation of malignancy and the need for operation. The routine use of FS is not warranted. Selective use of FS when FNAB is nondiagnostic or indeterminate may provide additional information. Both FNAB and FS fail to reveal occult carcinomas of thyroid.

Older age and larger tumor size predict malignancy in hürthle cell neoplasms of the thyroid

BACKGROUND

Hürthle cell neoplasms (HCNs) are rare tumors of the thyroid gland. The definitive treatment for Hürthle cell carcinoma (HCC) is total thyroidectomy, while thyroid lobectomy is adequate for Hürthle cell adenoma (HCA). However, differentiating HCC from HCA either before or during surgery is a challenge. The purpose of this study was to identify factors that predict malignancy in patients with HCN.

METHODS

Between May 1994 and January 2007, 1,199 patients underwent thyroid surgery at an academic medical center. Medical records of 55 consecutive patients who underwent thyroid resections for the preoperative diagnosis of HCN were reviewed.

RESULTS

Of the 55 patients with HCN, 46 (84%) had adenomas and 9 (16%) had carcinomas. Patients with HCC were significantly older than those with HCA (66 +/- 6 years versus 53 +/- 2 years, P = 0.01). Patients with carcinoma also had significantly larger thyroid nodules (4.5 +/- 0.7 cm versus 2.5 +/- 0.2 cm, P < 0.001). All HCNs less than 2 cm in diameter were benign. The malignancy rate increased with nodule size: 18% of nodules measuring 2-4 cm, and 44% of those larger than 4 cm were HCC. One patient with HCC had recurrence of the disease, but there were no disease-related deaths.

CONCLUSION

Advanced patient age and larger nodule size are two important factors that predict malignancy in patients with HCN. In patients with these and other known risk factors for HCC, total thyroidectomy should be considered.

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

BACKGROUND

Optimal surgical intervention is straightforward when a fine-needle aspiration (FNA) is diagnostic for papillary thyroid cancer (PTC). However, if there are characteristics of an aspirate suspicious for PTC but not meeting criteria for diagnosis of PTC, the management is less clear.

METHODS

Of the 1,051 patients who underwent thyroid surgery at the University of Wisconsin between May 24, 1994, and October 21, 2004, 102 had preoperative FNA cytology that was diagnostic or suspicious for PTC. Within the subgroups of diagnostic for PTC and suspicious for PTC, we evaluated the accuracy of FNA, the utility of frozen section (FS), and the predictive value of demographic and pathologic variables.

RESULTS

When diagnostic for PTC, FNA was 97% accurate and FS did not alter management. However, if an FNA was interpreted as suspicious for PTC, there was a 57% (17/30) likelihood of PTC on permanent histology. In this subgroup, FS led to the optimal operative procedure in 96% (25/26) of cases. With the exception of size greater than 4 cm, demographic and pathologic variables did not predict malignancy or increase the likelihood of an FNA being diagnostic for PTC.

CONCLUSION

Intraoperative FS is a useful diagnostic tool when an FNA is suspicious for PTC.

Clinical experience of the multimodality management of anaplastic thyroid cancer and literature review

Anaplastic Thyroid Carcinoma (ATC) is a rare thyroid tumor with a very aggressive clinical course. The following is a report of five patients with inoperable locally advanced disease treated at our institution using multimodality management consisting of chemotherapy and hyperfractionated accelerated radiotherapy. A flow diagram with management recommendations for inoperable ATC is suggested.

Fine-needle aspiration of thyroid nodules: a study of 4703 patients with histologic and clinical correlations

BACKGROUND

The Papanicolaou Society of Cytopathology recently proposed 6 diagnostic categories for the classification of thyroid fine-needle aspiration (FNA) cytology. Using these categories, the experience with FNA from 2 institutions was studied with emphasis on cytologic-histologic correlation, source of errors, and clinical management.

METHODS

Patient cytology data were retrieved by a retrospective search of thyroid FNA in the institutional databases. Cytologic diagnoses were classified as unsatisfactory, benign, atypical cellular lesion (ACL), follicular neoplasm (FN), suspicious for malignancy, and positive for malignancy. Samples with a histologic discrepancy were re-evaluated, and clinical follow-up information was recorded.

RESULTS

Of 4703 FNA samples, 10.4% were classified as unsatisfactory, 64.6% were classified as benign, 3.2% were classified as ACL, 11.6% were classified as FN, 2.6% were classified as suspicious, and 7.6% were classified as malignant. Five hundred twelve patients had at least 1 repeat FNA, mainly for results in the unsatisfactory and ACL categories. One thousand fifty-two patients had surgical follow-up, including 14.9% of patients with unsatisfactory FNA results, 9.8% of patients with benign results, 40.6% of patients with ACL results, 63.1% of patients with FN results, 86.1% of patients with suspicious results, and 79.3% of patients with malignant results. The rates for histologically confirmed malignancy in these categories were 10.9%, 7.3%, 13.5%, 32.2%, 64.7%, and 98.6%, respectively. The cytologic-histologic diagnostic discrepancy rate was 15.3%. Sources of errors included diagnoses on inadequate specimens, sample errors, and overlapping cytologic features between hyperplastic nodules and follicular adenoma. The sensitivity and specificity of thyroid FNA for the diagnosis of malignancy were 94% and 98.5%, respectively.

CONCLUSIONS

The current results indicated that FNA provides an accurate diagnosis of thyroid malignancy. The 6 diagnostic categories were beneficial for triaging patients for either clinical follow-up or surgical management.

Does Routine Consultation of Thyroid Fine-Needle Aspiration Cytology Change Surgical Management?

BACKGROUND

Routine secondary cytologic review of thyroid gland fine-needle aspiration (FNA) specimens in patients referred from other institutions has been the recommended practice at some medical centers. We sought to determine the concordance rates between FNA interpretations at referring institutions and our center to determine if they alter surgical management.

STUDY DESIGN

All thyroid gland FNAs referred to our center for cytopathologic opinion from June 2000 to August 2004 were reviewed. Patients in whom FNA biopsies were performed for thyroid cancer recurrences or core biopsies and patients in whom only a cytopathologic opinion was requested without a clinical consultation were excluded from the study. FNA results were divided into benign, indeterminate, suspicious, malignant, and nondiagnostic categories. FNA interpretations at our medical center and the referring institutions were compared with final histology results in patients who underwent operations.

RESULTS

One hundred forty-seven patients had secondary review of their thyroid gland FNA specimens. The overall concordance was 82%, with the highest concordance rate in the malignant category (95%) and the lowest in the suspicious category (62%, p<0.001). The sensitivity (94% versus 92%), specificity (76% versus 56%), and positive (93% versus 87%) and negative (79% versus 69%) predictive values were all higher on secondary review. Twenty-seven patients were found to have discordant FNA interpretations. As a result of the discordant FNA result, four patients had their surgical management decisions changed. Another four patients had appropriate oncologic thyroid resection as a result of the secondary review.

CONCLUSIONS

Our results suggest that routine secondary cytopathologic review of FNA specimens from referring institutions changes surgical management in some patients with thyroid neoplasms. We recommend this practice be widely used at other centers, especially for suspicious results.

Does Frozen Section Alter Surgical Management of Multinodular Thyroid Disease?

BACKGROUND

Frozen section (FS) evaluation during thyroid surgery is often used to guide intraoperative management. We sought to determine the utility of FS in patients undergoing thyroidectomy for multinodular thyroid disease.

METHODS

From May 1994 through November 2004, 236 patients with multinodular goiter underwent thyroidectomy at our institution. Patient data were retrospectively analyzed to see if a frozen section was performed during the procedure and whether it changed the patient's outcome.

RESULTS

Of the 236 patients, 135 (57%) had intra-operative FS. There were no differences between patients who had FS analysis and those who did not with regard to age, gender, and the incidence of malignancy. Of the patients who had FS, 4/135 (3%) were subsequently diagnosed with thyroid cancer on permanent histology. Three of these FS were misread as benign. Therefore, the sensitivity of FS for the diagnosis of thyroid cancer was only 25%. Importantly, in none of the 135 patients did FS alter the intraoperative management.

CONCLUSION

While FS was commonly used in patients undergoing thyroidectomy at our institution, in no patient over the last decade did FS correctly alter the intraoperative management. Given the time required to perform FS and the cost associated with it, we believe that routine FS should not be performed in these patients.

Anaplastic Thyroid Carcinoma, Thyroid Lymphoma, and Metastasis to Thyroid

Anaplastic thyroid carcinoma, thyroid lymphoma, and secondary metastasis to the thyroid gland are uncommon thyroid malignancies. They represent significant challenges for the surgeon owing to difficulties in diagnosis, aggressive biology, and the infrequency of their presentation. An awareness and appreciation of multimodality treatment strategies is essential for their management.