Robot-assisted laparoscopic nephron sparing surgery for tumors over 4 cm: operative results and preliminary oncologic outcomes from a multicentre French study

Abstract

Objective: To assess operative and pathological results obtained after robot-assisted partial nephrectomy (RAPN) in renal masses over 4 cm.

Patients and methods: Between 2007 and 2011, 220 robotic nephron-sparing surgeries (NSS) were performed at six French urology departments. Data were prospectively collected: age, BMI, pre and post-operative eGFR (MDRD), operative time (OT), warm ischemia time (WIT), estimated blood loss (EBL), length of hospital stay (LOS), Clavien complications, pathological results and oncologic outcome. Tumor complexity was assessed according to the RENAL nephrometry score.

Results: Overall, 54 tumors were included. Median follow up was 26 months. Median age at surgery was 62 years. Median RENAL nephrometry score was 7 (4-10). Median WIT was 23 min (10-59). Median OT and EBL were 180 min (110-425) and 100 cc (0-2500). Blood transfusion occurred in 7 cases (13%). Median tumor size was 45 mm (40-70). Three patients had positive surgical margins. Median LOS was 5 days (2-28). Nine patients presented post-operative complications of which 1/3 were considered as major (Clavien IIIb). Median pre-operative and post-operative eGFR was 88 (36-136) and 75 ml/min (33-122) (p = 0.01), respectively. Two patients developed subsequent metastasis. The 2-year progression free survival (PFS) rate was 90.5%.

Conclusion: Our results confirm that RAPN is a useful and acceptable approach for renal masses greater than 4 cm in size. When technically possible, NSS provides promising short-term cancer-specific survival rates with acceptable morbidity. Tumor size is not sufficiently discriminant enough and RENAL nephrometry score should increasingly used to describe tumor complexity.