Evaluation of Soft Tissue Tumors by Fine Needle Aspiration Cytology and Its Correlation with Histopathology: A Retrospective Study in a Tertiary Care Center

Soft tissue is a non-epithelial extraskeletal tissue of the body. Soft tissue tumors (STTs) are the most commonly diagnosed neoplasms. Fine needle aspiration cytology (FNAC) is minimally invasive, quick, and a definitive diagnostic modality. Biopsy for histopathology is the gold standard method for diagnosis but is invasive. The aims of this study were to determine the utility of FNAC in the diagnosis of STTs and correlate it with histopathology and to evaluate factors that cause discrepancies between FNAC and histopathology.

This retrospective, record-based study was done on STTs received for FNAC and histopathology examinations at the Department of Pathology, MIMS, Mandya from January 2018 to June 2021.

A total of 74 cases of FNAC with histopathological correlation were available. Seventy one cases (95.9%) were benign and three (4%) were malignant according to FNAC. Discordance was seen in one case of low grade myxofibrosarcoma, which was diagnosed as benign spindle cell tumor on FNAC. The sensitivity, specificity, positive predictive value, and accuracy of FNAC in diagnosing malignancy were 75%, 100%, 100%, and 98.6%, respectively.

Our findings indicate that FNAC is beneficial preoperatively as it differentiates between benign and malignant lesions in most cases. In the case of low grade myxofibrosarcoma, bland tumor cells led to a benign diagnosis on FNAC, but histopathology allowed sampling of a larger area of the tumor and the right diagnosis was made. Biopsy is the gold standard, but FNAC has high specificity in diagnosing malignant tumors and prevents unnecessary extensive, radical surgery for benign lesions.