Diagnostic utility of ultrasonography and fine needle aspiration cytology in the pre-operative assessment of suspicious thyroid nodules

Abstract

Introduction and Background: The incidence of thyroid cancer in Sri Lanka has risen over the last two decades. According to current national cancer statistics, it has become the second commonest cancer in females. Ultrasonography and fine needle aspiration cytology (FNAC) are pre-operative investigations that are useful to assess the nature of thyroid nodules. Though, majority of thyroid nodules are benign, it is vital to identify the suspicious nodules pre-operatively, to decide the most appropriate treatment option.Aim of the study was to determine the diagnostic utility of ultrasonography and FNAC in the pre-operative assessment of suspicious thyroid nodules in the local setting.Methodology: A descriptive cross-sectional study conducted at the Colombo South Teaching hospital and Department of Pathology, University of Sri Jayewardenepura enrolling 135 patients with ultrasonically suspicious thyroid nodules. Ultrasound guided FNAC samples were collected from each patient for cytological assessment. TIRADS (Thyroid Imaging Reporting And Data System) classification was used for radiological assessment and the Bethesda system for cytological interpretation. Data was analyzed using the SPSS 23 software.Results: The age of enrolled patients ranged from 15-76 years with a mean age of 49.8. Majority of the patients were females (81%) while 19% were males. Eleven FNAC specimens were excluded from the study due to insufficient cellularity. Classification of the cases according to ultrasound findings showed that the majority of the patients 51.61% (n=64) belonged to TI-RADS 3 (mildly suspicious). Thirty nine (31.45%) patients had moderately suspicious nodules (TIRADS 4) and 21 cases (16.93%) were highly suspicious.Conclusion: TI-RADS 5 category had the highest sensitivity and 100% concordance between the cytology and ultrasonography results.