Bellini duct carcinoma accompanied by hemorrhagic renal cyst: A case report and review of the literature

A 51-year-old female, who had undergone close follow-up for a right hemorrhagic renal cyst one year earlier, was admitted to our hospital in order to undergo examination of a newly developing tumor adjacent to the cyst, which had been found on ultrasonography and computed tomography. Aortography showed the downward displacement of the lower renal artery, but did not reveal any tumor vessels. Dark red fluid was aspirated from the cyst and the LDH level in the fluid was found to be very high (3042 U/ml). Urine cytological study resulted in class IV. Since small renal cell carcinoma was highly suspected according to these results, we performed right radical nephrectomy. According to the pathological findings, this tumor was not a renal cell carcinoma originating from the proximal tubules, but was a Bellini duct carcinoma originating from the collecting duct. Moreover, renal hilar lymph-node metastasis was present. She was treated with α-interferon and Tegafur postoperatively, but 4 months after surgery there was evidence of metastasis in the liver. She received chemotherapy of the M-VAC regimen, but after 1 cycle of this therapy, multiple liver metastases and retroperitoneal lymph node metastases were noted. We herein describe a case report and review the literature.