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Robot-assisted laparoscopic partial nephrectomy: Early single Canadian institution experience.

BACKGROUND
Although robot-assisted partial nephrectomy (RALPN) has been increasingly adopted, open procedures continue to be the reference nephron-sparing technique. We describe our initial surgical outcomes of RALPN in our single institution robotic program.


METHODS
Between January 2011 and February 2013, 65 consecutive patients underwent a RALPN by 2 surgeons. Preoperative characteristics, including the R.E.N.A.L. nephrometry score, perioperative parameters, and postoperative course, including renal function, were assessed from a retrospective database. The mean follow-up was 12 months.


RESULTS
The mean age was 60.2 years and the mean tumour size was 3.9 cm. According to the R.E.N.A.L. nephrometry score, the tumours were classified moderately and highly complex tumours in 51% and 18.5% of cases, respectively. Median warm ischemia time (WIT) was 21 minutes. Factors associated with WIT were R.E.N.A.L. nephrometry score, tumour size, complication rates and surgeon experience. No conversion or grade 4 to 5 complications were reported. The mean hospital stay was 3 days. The overall complication rate was 24.6% (re-admission rate 7.7%), and decreased to 12% after 20 cases. After these initial 20 cases, a trifecta rate (no margins, preserved renal function, no complications) of 64.3% was achieved in moderately and highly complex tumours. The mean change in estimated glomerular filtration rate was 6.7 mL/min without severe postoperative renal failure.


INTERPRETATION
RALPN is a safe and feasible procedure with low specific morbidity, even in moderately or highly complex renal masses. The WIT depends on tumour characteristics, mainly determined by the R.E.N.A.L. nephrometry score and is improved by surgeon experience. Longer follow-up is needed to assess the oncologic mid-term safety of the procedure.