Multiple ipsilateral renal tumors discovered at planned nephron sparing surgery: Importance of tumor histology and risk of metachronous recurrence

Purpose: Unrecognized sporadic multifocality at planned nephron sparing surgery (NSS) presents a surgical dilemma. We report a single institution experience with patients presenting with multiple ipsilateral renal tumors, of which at least 1 was renal cell carcinoma (RCC). We determined the outcome for patients treated with NSS or radical nephrectomy (RN). Materials and Methods: A total of 118 patients underwent surgery between 1970 and 2000 for sporadic multiple ipsilateral renal tumors, of which at least 1 was RCC. The patients were treated with RN (102) and NSS (16). Clinical features recorded included age at surgery, sex, history of smoking, a preexisting solitary kidney and symptomatic disease at presentation. Pathological features included histological subtype, nuclear grade, tumor stage (2003 TNM) and tumor size. Cancer specific survival was estimated using the Kaplan-Meier method. Results: A greater proportion of patients treated with NSS had a solitary kidney compared with patients treated with RN (6 or 38% versus 0, p <0.001). Of the 102 patients treated with RN for multiple tumors 12 died of RCC at a median time to death of 3.3 years (range 3 months to 9.5 years). Estimated cancer specific survival at 5 years was 90.1%. There was metachronous contralateral recurrence in 5 patients a median of 8.1 years following RN (range 3 months to 14 years). Two of the 16 patients treated with NSS died of RCC 6 and 11 years following NSS, respectively, for a cancer specific survival rate of 100% at 5 years. Two patients had local renal recurrence 1.7 and 2.8 years following NSS, respectively, and a metachronous contralateral renal tumor was found in 1 patient 7 months following NSS. Of the 102 patients treated with RN 63 (62%) and 9 of the 16 (56%) treated with NSS had at least 1 clear cell RCC. In 23 of the 102 patients (23%) treated with RN only 1 tumor was RCC, while the remainder were benign, suggesting that,these patients were potential candidates for NSS. Conclusions: Patients undergoing RN or NSS for multiple ipsilateral renal tumors, of which at least 1 is RCC, have favorable cancer specific survival. The metachronous contralateral recurrence rate for patients with sporadic multifocal lesions is approximately 5%. Planned NSS may not be abandoned if satellite lesions are benign.