Bilateral synchronous sporadic renal masses: intermediate functional and oncological outcomes at a single institution

To review the intermediate term oncologic and functional outcomes after the surgical management of bilateral renal masses (BRM).

After obtaining Institutional Review Board approval, the Tulane renal surgery database (n = 890 patients) was queried for patients presenting with synchronous bilateral enhancing renal masses (n = 30 renal units). We performed a retrospective chart review evaluating oncologic and functional outcomes, specifically with respect to local recurrence and metastatic disease. We also reviewed changes in glomerular filtration rates.

Of the 30 renal units were operated on for BRM concerning for renal cell carcinoma, 25 kidneys harbored malignancy (83.3 %). The average tumor size was 3.35 cm. Treatment of each kidney was staged; average time period to treatment of contralateral side was 3.5 months. Estimated GFR (eGFR) for these same pre-operative patients was 59 ml/min/1.73 m(2) (range 25-89). The average creatinine after treatment of one kidney was available for all patients and was 1.5 (range 0.7-2.8), with an average eGFR of 51.8 (range 29-87). The average creatinine after the second operation for these same 15 patients was 1.79 (range 0.9-3.7) with an average GFR of 41.9 (range 17-78). No patient had to undergo temporary dialysis. An average change in GFR after the second, contralateral procedure on the kidney was 17.07 mg/dl. Average oncologic follow-up was 608 days. Excluding two patients who presented with metastatic disease, the average recurrence-free survival was 92.8 %.

Our data continue to underscore the need for nephron sparing surgery (NSS), especially in the setting of BRM. The average decline in GFR of 28.9 % after treatment of both kidneys and renal cell carcinoma recurrence-free rate of 92.3 % further support the efficacy of NSS in these patients.