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Bilateral synchronous renal cancer.

Six cases of concurrent bilateral renal cancer are reported. These cases represented 3.7% of 163 renal cancers in our institute during the period 1965-1983. Five of the six cases were examined by CT. One earlier case received only selective renal arteriography. Three patients who had extrarenal metastases at the initial presentation showed poor prognoses and died within a year. The other three showed better prognoses. One had bilateral multiple renal cell cancer which was not associated with von Hippel-Lindau disease. One survived 4.5 years after unilateral nephrectomy and chemotherapy. One received unilateral total embolization combined with partial embolization of the contralateral kidney and is still well 1.5 years after initial diagnosis, without evidence of remote metastases. The smaller tumors of bilateral renal cancer were early in stage and were detected by CT. CT is thought to be the best method for detecting small asymptomatic tumors amenable to conservative surgery. Angiography is thought to be essential for the planning of embolization and partial nephrectomy. Although it is an interesting question whether each tumor has a multicentric origin or whether one is a metastasis of another, no criteria seem to exist which are completely satisfactory for making this distinction.