Laparoscopic partial nephrectomy is emerging as a viable minimally invasive nephron-sparing option for select patients with an exophytic renal tumor. With increasing experience, we are applying laparoscopic partial nephrectomy to tumors invading more deeply into the renal parenchyma, necessitating intentional caliceal entry to ensure an adequate margin of resection. In this prospective study, we assessed the safety and efficacy of such substantive renal parenchymal resections that incorporate laparoscopic suture repair of the collecting system.

Since August 1999, laparoscopic partial nephrectomy was performed in 64 patients with a renal tumor. Our technique routinely involved transient clamping of the renal artery and vein, caliceal suture repair (if necessary), and renal parenchymal suture repair. Intraoperative and postoperative data from the group requiring caliceal repair (group 1, n = 27) were compared with those not requiring caliceal repair (group 2, n = 37). The mean tumor size was 3.4 ± 1.6 cm in group 1 and 2.6 ± 0.9 cm in group 2 (P = 0.02). The mean depth of tumor invasion into the renal parenchyma was 1.5 ± 0.8 cm in group 1 and 0.9 ± 0.3 cm in group 2 (P = 0.15).

Laparoscopic partial nephrectomy was technically successful in all 64 cases without any open conversions. Both groups 1 and 2 were comparable in terms of total operative time (3.2 ± 0.9 hours versus 2.7 ± 1.0 hours, P = 0.06), tumor excision time (5.9 ± 1.8 minutes versus 6.0 ± 1.9 minutes, P = 0.97), and estimated blood loss (241 ± 306 mL versus 258 ± 342 mL, P = 0.27). Pelvicaliceal suture repair was associated with a longer warm ischemia time (30.2 ± 5.4 minutes versus 19.4 ± 4.9 minutes, P <0.0001), and a greater hospital stay (3.0 ± 1.7 days versus 1.8 ± 1.2 days, P = 0.003). No patients in group 1, and 1 patient in group 2, developed an asymptomatic perinephric urinoma that was drained percutaneously. On pathologic examination, inked surgical margins were negative for cancer in all but 1 case; the width of the parenchymal margin on histologic examination was 0.5 ± 0.4 cm in group 1, and 0.4 ± 0.3 cm in group 2 (P = 0.59). The mean preoperative and postoperative serum creatinine was 1.1 and 1.2 mg/dL in group 1 and 1.0 and 1.1 mg/dL in group 2, respectively (P = 0.4). During a mean follow-up of 9.5 ± 3.5 months in group 1 and 15.7 ± 4 months in group 2, no renal unit developed irreversible ischemic damage or local cancer recurrence.

Laparoscopic partial nephrectomy can be performed safely and efficaciously for select invasive renal tumors with intrarenal extension, even up to the collecting system. Intentional caliceal entry in such cases can be effectively repaired in a watertight manner by laparoscopic freehand suturing, albeit with longer mean operative and warm ischemia times, without adverse renal functional sequelae.