Thyroid Cytopathology Reporting by the Bethesda System: A Two-Year Prospective Study in an Academic Institution

Abstract

Background. The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) has attempted to standardize reporting and cytological criteria in aspiration smears. Aims. The objective of this study was to analyze the thyroid cytology smears by TBSRTC, to determine the distribution of diagnostic categories and subcategories, to analyze cytological features, and to correlate the cytopathology with histopathology, wherever surgery was done. Materials and Methods. This was a prospective study of 225 fine needle aspirations (FNA) of thyroid nodules. All fine needle aspiration cytology (FNAC) diagnoses were classified according to the features given in the monograph of TBSRTC into nondiagnostic/unsatisfactory (ND/UNS), benign, atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS), follicular neoplasm/suspicious of a follicular neoplasm (FN/SFN), suspicious for malignancy (SFM), and malignant. Cytohistological correlation was done, when surgical material was available. Results. The distribution of various categories from 225 evaluated thyroid nodules was as follows: 7.2% ND/UNS, 80.0% benign, 4.9% AUS/FLUS, 2.2% FN, 3.5% SFM, and 2.2% malignant. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated. Conclusions. TBSRTC is an excellent reporting system for thyroid FNA. It also provides clear management guidelines to clinicians to go for follow-up FNA or surgery and also the extent of surgery.

Kliniczne znaczenie rozpoznania zmiany pęcherzykowej bliżej nieokreślonej (grupa III wg Systemu Bethesda) w biopsji aspiracyjnej cienkoigłowej (BAC)

“…In 180 cases repeat FNA was performed, from which the diagnosis of DC I or DC II was established 109 times (60.5%); 41 (22.7%) patients again obtained DC III (36 were put under observation after that, five had another [third] FNA). The remaining 30 patients had DC IV, DC V, or diagnoses in six groups allowed improvement in the communication and specifying of the right clinical management [1][2][3][4][5][6].…”

“…The possibility of consultation between the competent pathologists regarding aspirates examination is essential. Most of the shown analyses concern the work of cytopathologists or pathologists that deal with cytological diagnostics of the thyroid on a daily basis [1,4,10,11]. The authors of one of the large studies base the initial diagnostics on the work of screeners.…”

Vanishing tumors of thyroid: histological variations after fine needle aspiration

“…The remaining ten nodules showed partial replacement of tumors by regressive changes (case 6,[8][9][10][11][12][13][14][15]17). These lesions had FNA diagnosis of indeterminate in five (FLUS in three, FN in one and suspicious for malignancy in one) and benign in five nodules.…”

“…However, 15-20% of the nodules are deemed indeterminate on cytological results (7). The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) uses three categories that fall in the "grey zone" between benign and malignant cytology: follicular lesion of undetermined significance/ atypia of undetermined significance (FLUS/AUS), suspicion for follicular neoplasm (FN)/Hürthle cell neoplasm, and suspicious for malignancy, the sensitivity of which is variable according to different investigators (7)(8)(9)(10)(11). The definite diagnosis of these nodules is provided by histological examination following surgical excision of the tumor.…”

Analiza znaczenia klinicznego niejednoznacznych wyników biopsji tarczycy ze szczególnym uwzględnieniem kategorii ZPBN na podstawie 5 lat stosowania nowej klasyfikacji rozpoznań cytologicznych

“…Those smears showed characteristics between SM and ND categories and in consequence were classified in the analysis as SM-low diagnostic. Because of the aforementioned factors the FLUS diagnosis constitutes, according to various authors, between 1% up to nearly 20% of all results [9,19,[24][25][26][27][28][29][30][31][32][33][34].…”