Abstract

Background: Fine-needle aspiration cytology (FNAC) is the initial screening test for thyroid nodules. The Bethesda system classifies thyroid FNAC into six categories. Each category is linked to a malignancy risk and has a recommended clinical management. The aim of this study was to analyze the thyroid cytology smears by Bethesda system and to correlate the diagnosis of cytopathology with ultrasound features.
Materials and Methods: This study was conducted at a tertiary care teaching hospital in Patna  for 6 months from May 2019-October 2019. Institute ethics committee approval was taken. The study included 100  patients  attending the pathology department for cytology of thyroid lump after direct or ultrasound guided FNAC.
Results: 8 patients (8%) were in category I. Out of 8 , 2 cases contained cyst fluid only, 2  had excessive blood obscuring the smear and 4 cases had scant cellularity. 64 patients (64%) were in category II. Among the 64 cases, 42 were labelled as goitre, 18 as lymphocytic thyroiditis, and 4 cases as granulomatous thyroiditis. 10 patients (10%) were in category III. Out of this,  2 cases had Atypia of undetermined significance and 8 cases had follicular lesion of undetermined significance. 8 cases(8%) were in category IV . Out of this, 6 cases were labelled as Follicular neoplasm and 2 as suspicious for follicular neoplasm. 2 cases (2%) were in category V and were labelled as suspicious for  papillary carcinoma.  8 cases (8%) were in category VI (malignant), out of this 4  were labelled as papillary carcinoma and 4 as anaplastic carcinoma of thyroid.
Conclusions: Fine-needle aspiration cytology (FNAC) of thyroid is a good initial screening test for thyroid nodules The Bethesda System for Reporting Thyroid Cytopathology proved to be an excellent reporting system.