Utility of tru-cut biopsy in diagnosis of palpable pediatric soft tissue neoplasms.

Context: Soft tissue neoplasms are infrequent in children with sarcomas accounting for approximately 7% of all pediatric malignancies. Morphologic diagnosis is challenging due to overlapping features. Subtyping and categorization of these lesions are difficult on fine-needle aspiration cytology (FNAC) alone owing to tumor heterogeneity and limited material in some cases. Tru-cut biopsies obtain adequate tumor tissue for ancillary studies besides conventional histology.

Aim: The study aims to explore the role of tru-cut biopsy to arrive at a definitive diagnosis. The study also highlights the correlation between FNAC and histopathology on tru-cut biopsy besides explaining the significance of a panel of immunohistochemistry (IHC) markers for histological categorization and subtyping.

Materials And Methods: A total of 61 children from infancy to 18 years were included in the study. Closed biopsy procedures like FNAC and tru-cut biopsy were performed, and the tru-cut biopsy specimen was subjected to a panel of immunohistochemical markers.

Results: Fisher's exact test for sensitivity and specificity towards detection of malignancy was 83% and 86%, respectively for FNAC. For tru-cut biopsy, sensitivity was 94% and specificity was 91%. The two-sided P value (<0.0001) was extremely significant. Cohen's Kappa coefficient value for tru-cut biopsy was 0.772 suggesting a substantial strength of agreement. Tru-cut with IHC had a Kappa value of 0.866 suggesting greater agreement with histopathology.

Conclusion: Tru-cut biopsy is a simple, safe, and reliable adjunct to the FNAC. Instead, immunohistochemistry enhances the diagnostic accuracy.