Laparoscopic partial nephrectomy with precise segmental renal artery clamping for clinical T1b tumors.

Objective: To assess the technique and short-term outcomes of laparoscopic partial nephrectomy (LPN) with precise segmental renal artery clamping for clinical T1b (cT1b) tumors and to analyze the possible factors affecting the glomerular filtration rate (GFR) reduction. Materials and Methods: This retrospective study investigated the outcomes of 72 patients with cT1b tumors who received LPN from June 2008 to May 2014. Based on three-dimensional dynamic renal vascular models built before surgery, target arteries were precisely clamped and tumors were removed under regional parenchymal ischemia. Perioperative and follow-up outcomes were analyzed. Results: All the LPN procedures were effectively performed using the novel technique, without converting to main renal artery clamping or open surgery. The mean operative time was 86min, with a mean warm ischemic time of 25min. The median estimated blood loss was 200mL (range: 80-800). The postoperative mean GFR was 64% of the preoperative baseline, and the total complication rate was 19.4%. In multivariable analyses, the two independent factors affecting postoperative GFR were the RENAL nephrometry score (RNS) and number of intraoperative clamped segmental arteries. The median follow-up was 24 months (range: 6-72). The overall, recurrence-free, and cancer-specific survival rates were 100%, 95.8%, and 100%, respectively. Conclusions: For patients with cT1b tumor, LPN with precise segmental renal artery clamping is safe and feasible for removing tumors and preserving the blood supply and normal renal parenchyma. Short-term oncologic and functional outcomes were satisfactory. Postoperative GFR was related to the preoperative RNS and number of intraoperative clamped segmental arteries.