Synchronous renal collecting duct carcinoma and transitional cell carcinoma: A case report

Renal carcinoma of the collecting ducts of Bellini account for less than 1% of all renal tumors. Here, we report a 57-year-old female with synchronous transitional cell carcinoma in the renal pelvis and collecting duct carcinoma in the renal parenchyma. In this challenging case, diagnosis was difficult and depended on pathological conclusions. Clinically, the renal cell carcinoma manifested as an inflammatory process. The tumor was confined to the renal medulla without distension of the renal capsule and was difficult to differentiate from renal cell carcinoma because of its unusual location. The patient received a radical nephrectomy and died of multiple metastases six months after the surgery. Preoperative tissue diagnosis, such as needle biopsy, should be performed first when radiological findings are suggestive of collecting duct carcinoma to enable proper treatment planning and prolong patient survival. We presented the imaging and histopathological findings of this rare case and the literature was reviewed.