Transperitoneal versus retroperitoneal robotic partial nephrectomy: matched-pair comparisons by nephrometry scores

The purpose of this study was to compare perioperative outcomes of transperitoneal (TP) and retroperitoneal (RP) robot-assisted partial nephrectomy (RPN) by matched analysis using nephrometry systems. A total of 107 patients who underwent RPN by a single surgeon from December 2008 to June 2012 were analyzed; 57 patients underwent TP RPN and 50 patients underwent RP RPN. Baseline demographic characteristics, perioperative outcomes and changes in renal function were collected by retrospective review of medical records. Matched-pair comparisons were done using RENAL score and C-index. No significant difference was observed between TP and RP RPN in patient age, body mass index, gender, laterality, clinical stage, tumor size, RENAL score or ASA score. The TP RPN had more cystic renal masses (TP vs. RP = 33 vs. 12 %, p = 0.012) and RP RPN had shorter median operation times (150 vs. 120 min, p = 0.015) and shorter mean warm ischemic times (26.2 vs. 22.6 min, p = 0.040) than TP RPN. In the matched-pair analysis, RP RPN showed shorter operation times with similar warm ischemic times. Estimated blood loss and visual analog pain scales showed no significant differences between groups. A total of 12 (11.4 %) postoperative complications occurred, all Clavien class I or II with no significant difference in incidence. Retroperitoneal robot-assisted partial nephrectomy showed shorter operation time and generally equivalent perioperative results to TP RPN. RP RPN is a viable treatment option for treating posterior or lateral renal masses.