We report a case of desmoplastic small round cell tumor (DSRCT) arising in the kidney of a 14 year old female. She presented with gross hematuria. Medical imaging found a left renal mass without regional or metastatic extension. The tumor showed morphological, immunohistochemical and molecular features of desmoplastic small round cell tumor. Immunostaining revealed polyphenotypic differentiation. Molecular analysis detected the fusion transcript resulting from the t(11;22)(p13;q12) reciprocal translocation which characterized this neoplasm. DSRCT is a rare, aggressive neoplasm that mainly affects young male, and usually presents with widespread abdominal serosal involvement. This unusual localization should lead to consider this tumor in the differential diagnosis of small blue round cell tumors of the kidney.

Keywords: Desmoplastic small round cell tumor, EWS-WT1 fusion transcript, immunophenotype, kidney