Malignancy rates for Bethesda III subcategories in thyroid fine needle aspiration biopsy (FNAB)

Abstract

OBJECTIVES:Most thyroid diseases are nodular and have been investigated using ultrasound-guided fine needle aspiration biopsy (FNAB), the reports of which are standardized by the Bethesda System. Bethesda category III represents a heterogeneous group in terms of lesion characteristics and the malignancy rates reported in the literature. The objective of the present study was to evaluate the differences in the malignancy rates among Bethesda III subcategories.METHODS:Data from 1,479 patients who had thyroid surgery were reviewed. In total, 1,093 patients (89.6% female, mean age 52.7 (13-89) years) were included, and 386 patients were excluded. FNAB results (based on Bethesda Class) and histopathological results (benign or malignant) for coincident areas were collected. Bethesda III patients were subcategorized according to cytopathological characteristics (FLUS: follicular lesion of undetermined significance, Bethesda IIIA; AUS: atypia of undetermined significance, Bethesda IIIB). Data were correlated to obtain the malignancy rates for each Bethesda category and the newly defined subcategory.RESULTS:FNAB results for these patients were as follows: Bethesda I: 3.1%; Bethesda II: 18.6%; Bethesda III: 35.0%; Bethesda IV: 22.1%; Bethesda V: 4.1%; and Bethesda VI: 17.1%. The malignancy rates for Bethesda Class IIIB were significantly higher than those for Bethesda Class IIIA (p<0.001) and Bethesda Class IV (p<0.001). Bethesda Class IIIA showed significantly lower malignancy rates than Bethesda Class III overall (p<0.001)CONCLUSIONS:Improvements of the Bethesda System should consider this subcategorization to better reflect different malignancy rates, which may have a significant impact on the decision-making process.

Risk Stratification of Thyroid Nodules with Bethesda III Category: The Experience of a Territorial Healthcare Hospital

“…According to the American Thyroid Association (ATA), the guidelines recommended for managing the treatment of thyroid cancer patients, based on the correlation of clinical and sonographic data, include (a) observation, (b) repeated fine-needle aspiration once in every three months, (c) diagnostic surgery, or (d) genetic testing) [2]. The gold standard for TN investigation is fine-needle aspiration cytology (FNAC), and the literature reports show FNA sensitivity varying from 65 to 99%, while the specificity varies from 72 to 100% [3]. These values are strongly dependent on examiner experience and other technical details [3].…”

The genetic heterogeneity of indeterminate thyroid nodules assessed preoperatively with next generation sequencing reflects the diversity of the final histopathological diagnoses

“…The previously described rates showed a considerable variation. For AUS / FLUS, the rates of 12%, 25 To analyze a putative function of mutations as driver mutations, we used 4 separate programs: SIFT (Sorting Tolerant From Intolerant) algorithm, 13 PolyPhen -2, 14 MutationTaster2, 15 as well as FATHMM (Functional Analysis through Hidden Markov Models v2.3), which result in an index, calculated with a high -throughput webserver, able to predict the functional consequences of coding variants (ie, nonsynonymous single nucleotide variants) and noncoding variants to distinguish between cancer -promoting or driver mutations and other germline polymorphisms.…”

High risk of malignancy in cases with atypia of undetermined significance on fine needle aspiration of thyroid nodules even after exclusion of NIFTP

“…Most thyroid diseases occur in a nodular form and can reach a prevalence of up to 68% in adult women. 1 In the management of thyroid nodules, distinguishing between potentially malignant nodules that require further treatment and those that are benign and do not require operative intervention creates a clinical and diagnostic dilemma. 2 Although thyroid nodules are often benign, the malignancy rate is 5% to 17% and is increasing steadily worldwide.…”

“…It involves some subjectivity, reflecting the difficulty in cytopathologically diagnosing follicular lesions, and this subjectivity is strongly associated with the interpretation of the pathologist. 1 Although TBSRTC has standardized the terminology for reporting thyroid cytopathology to improve communication regarding RoM, and ultimately patient management, there does not exist, as many believe, a set of objective criteria that eliminates subjectivity. 12 A comprehensive study showed that the reproducibility of AUS/FLUS is only 50%, even among expert thyroid cytopathologists.…”