Feasibility of Robotic Laparoendoscopic Single-Site Partial Nephrectomy for Renal Tumors >4 cm

Abstract

BACKGROUND: Laparoendoscopic single-site (LESS) urologic procedures have gained significant interest worldwide in an attempt to further reduce morbidity and minimize scarring associated with conventional laparoscopic surgery. The robotic technology has overcome some of the limitations of manual single-incision surgery relating to lack of triangulation, instrument collision, and surgical exposure. There are no data on robotic LESS partial nephrectomy (PN) for renal tumors >4 cm. OBJECTIVES: To evaluate the feasibility of robotic LESS PN for renal tumors >4 cm. DESIGN, SETTING, AND PARTICIPANTS: Data from 67 consecutive patients who underwent robotic LESS PN were collected between May 2009 to January 2011. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Patients were stratified into two groups: 20 patients with renal tumors >4 cm (group 1) and 47 patients with renal tumors ≤ 4 cm (group 2). Perioperative data were recorded and comparisons between the two groups were analyzed using the Mann-Whitney U test for continuous variables and Fisher exact test for categorical variables. RESULTS AND LIMITATIONS: No statistically significant differences were found between the two groups in demographic information, operative complications, pathologic characteristics, mean decline in estimated glomerular filtration rate, estimated blood loss, operative times, conversion rate, or positive surgical margins. However, group 1 had a higher mean nephrometry score (p<0.01), longer warm ischemia time (p = 0.007), and longer length of stay (p = 0.046). Its retrospective design and being conducted at a single center were the main limitations of this study. CONCLUSIONS: This study demonstrated the feasibility and safety of robotic LESS PN for tumors >4 cm. Patients with tumors >4 cm had a statistically significant, higher mean nephrometry score, longer warm ischemia time, and longer length of stay, but there was no increased risk of adverse outcomes. A long-term study is needed to confirm the durable renal preservation and oncologic outcomes for patients with larger tumor burden.