Fine needle aspiration cytology of soft tissue tumors with its histopathological correlation in a rural hospital of South India: A retrospective study

Background: Fine needle aspiration cytology (FNAC) is often considered as the initial mode of investigation in the evaluation of the soft tissue tumors (STTs). This study was undertaken to explore the utility and accuracy of FNAC in STT by correlating their histopathological diagnoses. Materials and Methods: A total of 220 FNAC of STT was retrieved and evaluated retrospectively between January 2012 and June 2015 and correlated with their subsequent histopathological diagnoses. Results: On FNAC, 175 (79.6%) were benign, 26 (11.8%) were malignant and 19 (8.6%) were inconclusive. On the correlation of subsequent histopathology, 173 cases were confirmed as benign (true negative) and 22 cases were confirmed as malignant (true positive). There were four false positive and two false negative results. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive values of FNAC for diagnosing malignant STT were 91.7%, 97.7%, 97%, 84.6%, and 98.9%, respectively. Conclusion: The present study concluded that FNAC can be used as a reliable diagnostic tool for preoperative triaging of benign and malignant STT with fair sensitivity, specificity, and accuracy, even though a specific diagnosis may not be possible in all cases. In addition, we have found a considerable proportion of difficulties in the diagnosis of certain STT; hence, care should be taken while interpreting these challenging FNAC cases.