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.

Keywords

• cytology
• false-negative rate
• false-positive rate
• papillary thyroid carcinoma