Endoscopic robot-assisted simple enucleation (ERASE) for clinical T1 renal masses: description of the technique and early postoperative results.

Abstract BACKGROUND: Simple enucleation (SE) has proven to be oncologically safe. We describe the surgical steps and report the results of the Endoscopic Robotic-Assisted Simple Enucleation (ERASE) technique. METHODS: Data were gathered prospectively from 130 consecutive patients undergone ERASE for intracapsular kidney cancer, between 2010 and 2013. ERASE was performed using the 4S Da Vinci surgical system, (Intuitive Surgical, Sunnyvale, CA, USA) in a three-arm configuration. Patients' characteristics and surgical outcomes of ERASE in cT1 were analyzed and the results in cT1a tumors were compared to those of pure laparoscopic SE performed in the same institution in the same time period. RESULTS: The mean (range) preoperative tumor size was 3.2 cm (0.8-10.0 cm), and clinical stage was T1a for 101 patients, T1b for 28, and T2a for 1. Median PADUA score was 8 (IQR 7-9). In 33.9 % of patients, ERASE was done without pedicle clamping. Mean (±SD) warm ischemia time (WIT) was 18 ± 6 min. According to Clavien system, 1 grade 1 (0.8 %), 5 grade 2 (3.1 %), 4 grade 3 (3.8 %), and 1 grade 4 (0.8 %) surgical complications occurred. Positive surgical margin (PSM) rate was 2.8 %. ERASE in cT1a tumors was associated with a significantly lower need for pedicle clamping, shorter WIT, and lower estimated blood loss (EBL) along with similar operative time and intra and postoperative complication rates but with a significantly lower incidence of urinary fistulas requiring stent insertion compared to laparoscopic SE. Also mean time to drainage removal and length of hospital stay (LOS) were significantly lower in for ERASE. The two groups had comparable PSM rate. CONCLUSIONS: ERASE has proven to be a feasible technique for the minimal invasive treatment of clinical stage T1 renal masses. The robotic approach can achieve surgical results superior to those of pure laparoscopy by reducing the need for clamping, WIT, EBL, and LOS