Diagnostic accuracy of fine-needle aspiration cytology of thyroid gland lesions by using The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC): A retrospective study from January 2019 to August 2021 in tertiary care institute

Background: Fine needle aspiration cytology (FNAC) plays important role in diagnosis of thyroid lesions properly. However conventional reporting method of thyroid cytology do not have standardize format. To overcome this hurdle because of lack of standardization and to facilitate communication between cytopathologist and clinician, "The Bethesda System for Reporting Thyroid Cytopathology" (TBSRTC) was proposed at Bethesda in 2007. Aims: Main Objective of this study was to classify and study thyroid FNACs according to TBSRTC, calculate malignancy risk and to determine the distribution of diagnostic categories and subcategories, to analyze and study cytological features of thyroid lesions. Materials and methods: All the FNAC of thyroid lesions came during January 2019 to August 2021 were classified in to six categories of TBSRTC. Distribution of cases in each category was calculated. Cytopathology analysis was carried out and classified according to TBSRTC categories. Results: During the study period, total of 147 thyroid FNACs were reported according to TBSRTC. Non diagnostic(ND), benign, atypical follicular lesion of undetermined significance(AFLUS), follicular neoplasm(FN), suspicious of malignancy(SM) and malignancy were reported in 6.8%, 80.9%, 0%, 6.8%, 2% and 3.5% cases respectively. Conclusion: Use of TBSRTC guideline for thyroid Cytopathology reporting helps to improve communication and give diagnostic criteria between cytopathologist and clinician leading to most effective management. Also interlaboratory comparative results provide data in a standardize pattern to compare between all different studies related to cytology of thyroid lesions