Cytohistopathological and Immunohistochemical correlation of soft tissue tumors: A retrospective study at a tertiary care rural hospital in central India

BACKGROUND: Soft tissue tumors (STT) are rare, heterogeneous neoplasm, derived from the mesoderm. The wide range of STT and absence of recognizable architectural patterns on cytology makes the diagnosis of STT through fine needle aspiration cytology (FNAC) difficult. METHODS: This laboratory-based, non–interventional, observational, retrospective study was conducted on 526 diagnosed cases of STT between 2015 and 2019, for cytohistological correlation. In all the cases, complete clinical details, radiological and clinical data, and cytopathological and histopathological diagnosis were recorded from the Hospital Information System and pathology records. The cytological smears were examined and were categorized as benign, suspicious for malignancy, and malignant. Corresponding histopathology slides were examined for diagnostic concordance considering histopathology as the “gold standard.” Cytohistopathological correlation was assessed in all cases and the diagnostic accuracy of FNAC was expressed as a percentage. Statistical analysis was carried out using SPSS software. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV)‎ were calculated using the respective formulae. P values < 0.05 were considered to be significant. RESULTS: Overall accurate categorizations of benign STT and malignant STT were 61.96% and 17.05%, respectively. The overall diagnostic accuracy of FNAC was 93.5%. Its sensitivity, specificity, PPV, and NPV were 83.68%, 97.39%, 91.47%, and 94.20%, respectively. Correlations with a p value < 0.001 were considered significant. CONCLUSION: FNAC is an important preliminary diagnostic tool in STT and is helpful in the diagnosis of local recurrence and metastatic tumors in the soft tissue. FNAC has a high degree of correlation with core biopsy, thereby avoiding significant clinical complication associated with it.