The feasibility and safety of modified robot-assisted enucleation for highly complex renal tumors: research on a surgical technique

Background: To report the technical feasibility and oncological safety of modified robot-assisted enucleation for highly complex renal tumors using the combined retroperitoneoscopic and transperitoncoscopic accesses. Methods: The present research is a retrospective analysis of 166 cases of highly complex renal tumors that underwent a partial nephrectomy at a tertiary academic institution between September 2014 and August 2017. Consecutive consented patients were grouped into two cohorts. Seventy-two cases underwent conventional robot-assisted partial nephrectomy (C-RAPN), and 94 cases were treated with modified robot-assisted tumor enucleation (MRATE). The perioperative and oncological outcomes of both groups were reported. Furthermore, pathological examinations of 225 cases of highly complex renal tumors treated with radical nephrectomy were analyzed. Results: Although preoperative clinical data were similar between the two groups, the perioperative outcomes were distinctly different. Total renal function at postoperative day 1 was better (P<0.001), and the surgical margin width was narrower (P<0.001) in the MRATE group. In addition, the M RATE group presented less blood loss (143.29 and 90.76 mL; P<0.001) and lower 30-d complication rates (4.2% and 16.7%, respectively; P=0.033). Mean ischemia time and operative time was 3 and 14 minutes shorter in the MRATE group, respectively. Finally, histopathological analysis of 225 cases of renal tumors with high surgical complexity provided objective evidence for the feasibility of MRATE. Conclusions: MRATE technique may offer an efficient and safe method to treat anatomically complex renal masses in referral centers. The long-term outcome of MRATE technique merits further investigation.