Comparative analysis of laparoscopic versus open partial nephrectomy for renal tumors in 200 patients.

PURPOSE: Laparoscopic partial nephrectomy is an emerging minimally invasive, nephron sparing approach for renal cell carcinoma. We compared perioperative outcomes after laparoscopic and open nephron sparing surgery (NSS) for patients with a solitary renal tumor of 7 cm or less at a single institution.

MATERIALS AND METHODS: Since September 1999, 100 consecutive patients have undergone laparoscopic partial nephrectomy for a sporadic single renal tumor of 7 cm or less at our institution. A contemporary cohort of 100 consecutive patients with similar inclusion criteria have undergone open NSS since April 1998. Since our laparoscopic technique was based on our established open surgical principles, the 2 approaches were similar, including transient renal vascular control, sharp tumor excision in a bloodless field, pelvicaliceal repair when necessary, suture ligation of transected intrarenal blood vessels and suture repair of the renal parenchymal defect over a bolster. Demographic, intraoperative, postoperative and short-term followup data were retrospectively compared between the 2 groups.

RESULTS: Median tumor size was 2.8 cm in the laparoscopic group and 3.3 cm in the open group (p = 0.005). There were significantly more tumors greater than 4 cm in the open group (p <0.001). There were more patients with a solitary kidney in the open surgical group (p = 0.002). More patients in the open group underwent NSS for a malignant tumor (p = 002). Comparing the laparoscopic versus open groups, median surgical time was 3 vs 3.9 hours (p <0.001), blood loss was 125 vs 250 ml (p <0.001) and mean warm ischemia time was 27.8 vs 17.5 minutes (p <0.001), respectively. In the laparoscopic and open groups median analgesic requirement was 20.2 vs 252.5 mg morphine sulfate equivalents (p <0.001), hospital stay was 2 vs 5 days (p <0.001) and average convalescence was 4 vs 6 weeks (p <0.001). Median preoperative serum creatinine (1.0 vs 1.0 mg/dl, p = 0.52) and postoperative serum creatinine (1.1 vs 1.2 mg/dl, p = 0.65) were similar in the 2 groups. No kidney was lost due to warm ischemic injury. Three patients in the laparoscopic group had a positive surgical margin compared to none in the open groups (3% vs 0%, p = 0.1). Laparoscopic NSS was associated with a higher rate of major intraoperative complications (5% vs 0%, p = 0.02). There were no significant differences in overall postoperative complications, although renal/urological complications were more common in the laparoscopic group (11% vs 2%, p = 0.01).

CONCLUSIONS: Open surgical partial nephrectomy remains the established standard for nephron sparing treatment of renal tumors. When applied to small renal tumors, the laparoscopic approach is associated with longer warm renal ischemia time, more major intraoperative complications and more postoperative urological complications. Our data also suggest that more deliberate efforts to achieve a wider surgical margin are necessary with the laparoscopic approach. Nevertheless, our data suggest that laparoscopic NSS is emerging as an effective, minimally invasive therapeutic approach with respect to renal functional outcome with the additional advantages of decreased postoperative narcotic use, earlier hospital discharge and a more rapid convalescence. Continued efforts are required to develop laparoscopic renal hypothermia techniques and facilitate intrarenal suturing, while minimizing warm ischemia time.