[Transitional cell carcinoma of the renal pelvis with cystic formation: a case report].

A 75-year-old man consulted our hospital complaining of gross hematuria. Retrograde pyelography revealed a filling defect and deformity of the upper calix of the left kidney. Abdominal echography and computed tomography revealed a left renal cystic tumor with irregular wall thickness measuring 7 by 5 cm. As left renal pelvic tumor or left renal cell carcinoma was suspected, left total nephroureterectomy was performed. Macroscopically, the cystic tumor contained a papillary tumor connected to the renal pelvis and histopathological diagnosis was grade 1 transitional cell carcinoma. Cystic formation caused by obstruction of the upper calix was suspected. After adjuvant chemotherapy, he has been well without recurrence or metastasis for 19 months after the operation. This is the 15th case of renal pelvic tumors with cystic formation including tumors in the pyelocaliceal diverticulum reported in Japan.