[Synchronous ipsilateral renal cell carcinoma and transitional cell carcinoma: report of 2 cases].

Two cases of synchronous ipsilateral renal cell carcinoma and renal pelvic transitional cell carcinoma are presented, one in a 70-year-old man and another in a 54-year-old man. These two cases were diagnosed preoperatively as synchronous ipsilateral renal tumor and pelvic tumor from urine cytology, retrograde pyelography, computed tomography and magnetic resonance imaging, and in both two cases, nephroureterectomy was performed. Pathological diagnosis was renal cell carcinoma and renal pelvic transitional cell carcinoma, which existed incidentally in the same kidney. To our knowledge, these cases are the 34th and 35th reported cases of synchronous ipsilateral renal cell carcinoma and renal pelvic transitional cell carcinoma in Japan.