Renal cell carcinoma metastatic to the gallbladder or prostate: two case reports.

Although metastatic renal cell carcinoma (RCC) is not uncommon, dissemination to the gallbladder or prostate is very rare. We present 1 case of RCC with synchronous metastasis to the gallbladder and 1 case of RCC with metachronous metastasis to the prostate. These cases illustrate the propensity of RCC for unpredictable presentation and unusual sites of metastases. The first case also illustrates the benefit of adjuvant nephrectomy with excision of a solitary metastasis. Patterns of RCC metastases and flow cytometric analysis of RCC are discussed.