Collecting duct carcinoma with acquired cystic disease of the kidney in a long-term hemodialysis patient.

We report a very rare case of collecting or Bellini duct carcinoma (CDC) found in a 60-year-old male who had received hemodialysis therapy for 21 years. Screening with ultrasonography revealed a solid tumor originating from the cyst wall in the right kidney with acquired cystic disease of the kidney. Subsequent computed tomography (CT) and angiography could not detect another renal tumor. Right radical nephrectomy was performed. The tumor detected preoperatively was composed of papillary renal cell tumor (RCC) and multiple clear cell carcinoma, pathologically. In addition to the tumors, CDC was revealed in the central medulla with the involvement of regional lymph nodes. Three months later, left nephrectomy was performed because left RCC was suspected during CT. The histological diagnosis was multiple clear cell carcinomas. Peritonitis carcinomatosa appeared and the patient died 13 months later.