Laparoscopic partial nephrectomy for tumors larger than 4 cm: a comparative study

To compare the perioperative and functional outcomes of patients with clinical T(1a) and T(1b) renal tumors after laparoscopic partial nephrectomy (LPN).

Data of 184 patients who underwent LPN were retrieved from a prospective, Institutional Review Board-approved database. The patients were stratified for analysis into groups: 149 (81%) patients with clinical stage T(1a) (group 1) and 35 (19%) patients with clinical stage T(1b) (group 2). Perioperative and postoperative outcomes were compared.

No significant differences between groups 1 and 2 in warm ischemia time, estimated blood loss, operative time, conversion rate, intraoperative complication rate, and hospital stay were observed. The incidence of postoperative complications in group 2, however, was twice that of group 1 (25.7% vs 12%) (P = 0.04). Clinical staging correlated with the pathologic staging in 96% of the patients in group 1 and in only 71% in group 2 (P < 0.001). Upstaging to pT(2) or pT(3) occurred in 29% of the patients in group 2. High-grade tumors were more prevalent in group 2 (36% vs 12%) (P = 0.001). The number of patients with positive margin was higher in group 2, but the difference was not statistically significant. The mean decline in estimated creatinine clearance (median follow-up 18 months) was significantly higher in group 2.

LPN in patients with tumors >4 cm, while safe and feasible in experienced hands, is associated with a higher postoperative complication rate, as well as a higher rate of pathologic upstaging. Such data should be discussed when counseling patients with larger tumors for LPN.