Objective To investigate the safety and efficiency of robot-assisted partial nephrectomy (RAPN) for totally intrarenal tumors (TITs).Methods Thirty-eight patients who underwent RAPN for treating TITs by one experienced surgeon were included between August 2012 and December 2017.There were 25 males and 13 females,aged 26-72 years(mean 51.6 years).Tumors of 24 cases were in right kidney,and 14 cases in left kidney.The diameter of tumor was(3.12 ± 0.92) cm,the R.E.N.A.L.score was(9.76 ± 1.00),and the Scr was (74.82 ± 20.32) μmol/L.Patients' peri-operative and oncological outcomes were analyzed.Results All the tumors were successfully resected without conversion to open surgery or radical nephrectomy.Mean operative time and ischemia time were (188.47 ± 46.75) min and (24.32 ± 7.69) min.Mean blood loss was (115.79 ± 43.66) rrd.One-week postoperative Scr was (85.97 ± 28.33) μmol/L.Postoperative hemorrhage was successfully treated by DSA or drug therapy in 3 patients.The pathological examination showed 28 clear cell renal cell carcinomas,3 chromophobe renal cell carcinomas,3 TFE-3 infusion related renal cell carcinomas,2 metanephric adenomas,1 acidophile adenoma and 2 angioleiomyolipomas.One positive surgical margin occurred in RAPN group for cystic components.No evidence of tumor progression observed during follow-up.Conclusions RAPN is safe and effective in treating TITs when performed by an experienced surgeon at a high-volume institution.Further prospective and large-scale study was warranted to evaluate the long-term outcomes.

Objective To compare the operative-postoperative outcomes of laparoscopic and robotassisted partial nephrectomy (LPN and RAPN) for patients with T1 b renal masses.Methods A total of 169 T1 b renal mass patients receiving LPN (n =69) or RAPN (n =100) in our center between October 2009 and October 2017 were retrospectively collected.There were 46 males and 23 females in LPN group,with a mean age of (55.0 ± 11.9) years.The mean tumor size was (5.09 ± 0.76) cm,and mean R.E.N.A.L score was 6.36 ± 1.53.49 procedures (71％) were performed via a retroperitoneal approach in LPN group.There were 59 males and 41 females in RAPN group with a mean age of (52.9 ± 11.7) years.The mean tumor size was(4.95 ±0.66) cm,and mean R.E.N.A.L score was 8.17 ± 1.50.31 procedures (31％)were performed via a retroperitoneal approach in RAPN group.There was statistical significance between two groups in R.E.N.A.L score and surgery approach (P ＜ 0.001).The group covariates were balanced through propensity score matching (PSM) using 1∶ 1 nearest neighbor matching method.After PSM,operating time,estimated blood loss,warm ischemia time,incidence of complications,hospital stay and postoperative follow-up status were compared between LPN(n =36)and RAPN(n =36)group.Results After PSM,patient distributions were closely balanced.In the LPN vs the RAPN group,there were significant different in warm ischemia time [(23.9 ± 7.3) min vs.(20.4 ± 6.7) min,P ＜ 0.05],estimated blood loss [(136.9 ± 80.2) ml vs.(136.9 ± 80.2) ml,P ＜ 0.05],incidence of complications (8.7％ vs.1.0％,P ＜0.05),and hospital stay [(11.5 ±3.8)d vs.(9.8 ± 1.80)d].There was no significant differences resulted regarding operating time [(164.5 ± 64.4) min vs.(169.0 ± 42.5) min,P ＞ 0.05],variation of estimated glomerular filtration rate from baseline [(9.97 ± 8.98)％ vs.(9.27 ± 9.19)％,P ＞ 0.05],positive surgical margin rate (1.4％ vs.0,P ＞ 0.05) and rate of recurrence or metastasis (1.4％ vs.1.4％,P ＞ 0.05) between groups.Conclusion Considering operative,functional and oncologic outcomes,both RAPN and LPN performed by an experienced surgeon were acceptable for patients with T1b renal masses.If available,robotic approach may reduce operative trauma and complications.