Melanotic Xp11 Translocation Renal Cell Carcinoma—A Case Report

A BSTRACT Translocation-associated renal cell carcinomas are a rare subset of renal epithelial malignancies, most commonly occurring in the pediatric and young adult population. The Xp11.2 translocation-associated renal cell carcinoma is defined by recurrent gene rearrangements involving the Transcription Factor E3 ( TFE3 ) gene and demonstrates a female predominance. Radiological imaging, particularly contrast-enhanced computed tomography, plays a key role in detecting the renal mass, while surgical excision remains the treatment of choice. Histopathological examination typically reveals features overlapping with clear cell and papillary renal cell carcinoma. Ancillary studies will help in the confirmation of the diagnosis. The melanotic variant of TFE3-rearranged renal cell carcinoma is exceedingly rare, with only 20 cases documented in the literature. The present case represents the 21 st reported instance of this entity and will aid in expanding the limited clinicopathological understanding, raising diagnostic awareness and reinforcing the critical role of immunohistochemistry in accurate recognition and management of similar cases in clinical practice. We report a case of a 13-year-old girl who presented with fullness of the flank. A contrast-enhanced computed tomography (CECT) revealed a right renal mass. Histopathology showed features of melanotic TFE3 rearranged renal cell carcinoma, which was confirmed by Immunohistochemistry.