Xp11 Translocation Renal Cell Carcinoma: Unusual Variant Masquerading as Upper Tract Urothelial Cell Carcinoma

Xp11 translocation renal cell carcinoma (TRCC) is a rare subtype of renal cell carcinoma characterized by chromosomal translocations involving the TFE3 gene located at the Xp11.2 locus. Initial cases were more common in children, but cases in older adults have begun to accrue and suggest a relatively more aggressive course. We report a case of Xp11 TRCC in a 63-year-old female patient with initial presentation mimicking upper urinary tract urothelial cell carcinoma, with biopsy proving TRCC. She underwent a radical nephrectomy and paracaval lymph node dissection and is followed up with the intent to initiate vascular endothelial growth factor-targeted therapy in case of recurrence.