Appraisal of Cytohistomorphology of Papillary Carcinoma Thyroid and its Variants with Evaluation of Discrepant Cases

Abstract

Background: Papillary carcinoma thyroid is the most commonly occurring thyroid neoplasm which can be diagnosed by its characteristic cytological features by fine‑needle aspiration procedure. Due too few limitations in fine‑needle aspiration cytology (FNAC) technique, there are false‑positive and false‑negative diagnoses in papillary carcinoma thyroid lesions. Aim: In our study, we would like to evaluate the accuracy of thyroid FNAC and to determine the reasons for cytopathological discrepancies. Materials and Methods: Two hundred and twenty‑three cases were collected from archives of our Department of Pathology. Slides were retrieved for which cytohistopathology correlation differed and reviewed. Statistical analysis for False positive/ negative rates, positive predictive value, sensitivity and specificity were done. Results: For 170 cases, cytohistopathology correlation, 27 cases were discordant which accounted for 15.2% of false‑negative rates. 87% sensitivity, 96.6% positive predictive value and 10.6% false positive were calculated. Conclusion: FNAC is a reliable screening procedure in spite of having few pitfalls. Awareness of these pitfalls, while reporting by cytopathologist can minimize false‑positive and false‑negative reporting on thyroid lesions.