Risk factors for recurrence following robot-assisted laparoscopic partial nephrectomy (RAPN): a single-center retrospective study

BACKGROUND: The recurrence rate after robot-assisted laparoscopic partial nephrectomy (RAPN) for renal cell carcinoma varies, and few established risk factors have been identified. We investigated recurrence rate and its risk factors following RAPN. METHODS: Among 221 patients who underwent RAPN at our institution from 2016 to 2024, we analyzed 205 patients diagnosed with renal cell carcinoma (excluding benign diseases). We retrospectively examined recurrence rates and risk factors. RESULTS: Postoperative recurrence was observed in 11 cases: 3 local recurrences and 8 non-local recurrences. The postoperative recurrence rate was 5.3%. The overall median follow-up duration for the full cohort was 63.5 months and the median time to postoperative recurrence was 15 months. Regarding perioperative findings, sex, lateral perirenal fat thickness, dorsal perirenal fat thickness, tumor size, operative time, warm ischemia time, pathological tumor (pT) stage ≥ 3a, and Fuhrman grade ≥ 3 were associated with postoperative recurrence status. A Cox regression analysis for recurrence-free survival was performed on factors associated with postoperative recurrence in the univariate analysis, and hazard ratios (HRs) were calculated. In particular, it was indicated that pT stage ≥ 3a (HR: 8.2, 95% confidence interval (CI): 2.0-33.8; p < 0.01) and Fuhrman grade ≥ 3 (HR: 9.2, 95% CI: 2.5-33.8; p < 0.01) might be associated with recurrence. However, postoperative recurrence occurred in only one of the seven cases with positive surgical margins, suggesting that no significant association was detected between positive surgical margins and recurrence in this cohort. Thirty-seven (18%) patients had either pT stage ≥ 3a or Fuhrman grade ≥ 3 (high-risk group). Compared with the 169 patients in the low-risk group (i.e., neither pT stage ≥ 3a nor Fuhrman grade ≥ 3), RFS was significantly shorter in patients meeting either criterion (HR: 15.6; 95% CI: 4.1-59.9; p < 0.01). CONCLUSION: Positive surgical margin was not significantly associated with recurrence after RAPN for renal cell carcinoma, whereas pT stage ≥ 3a and Fuhrman grade ≥ 3 may be associated with recurrence. These findings should be interpreted with caution due to the limited number of events and require validation in larger studies.