Objective: To evaluate the safety, efficacy, and potential advantages of off-clamp partial nephrectomy (OFF-PN) compared with on-clamp partial nephrectomy (ON-PN).
Methods: Relevant studies comparing the safety and efficacy of OFF-PN to ON-PN were identified through a literature search using MEDLINE, EMBASE, and the Cochrane Library. The outcome measures included baseline characteristics, primary outcomes, and secondary outcomes.
Results: Ten retrospective studies (728 cases and 1267 controls) were included. No significant differences between the two groups were detected in any of the baseline variables (age: p=0.19; sex: p=0.49; BMI: p=0.29; tumor size: p=0.44, pre-eGFR: p=0.78) except for tumor location (p<0.001). The OFF-PN group had a higher blood transfusion rate (odds ratio [OR] 1.54, 95% confidence interval [CI] 10.7-2.21, p=0.02), a lower postoperative complication rate (OR 0.61, 95% CI 0.44-0.83, p=0.002), and a lower positive margin rate (OR 0.49, 95% CI 0.26-0.90, p=0.02) than ON-PN. OFF-PN offered a better preservation of renal function than ON-PN (p=0.005). No significant differences were detected between the two groups in other outcomes of interest. In sensitivity analysis, there was no change in the significance of any of the outcomes except for postoperative complication rate (OR 0.91, 95% CI 0.53-1.5, p=0.73) and positive margin rate (OR 0.55, 95% CI 0.25-1.23, p=0.15).
Conclusions: This meta-analysis suggests that with appropriate patient selection, OFF-PN offer comparable perioperative safety, equivalent oncologic outcomes, and superior long-term renal function preservation when compared with ON-PN for renal cell carcinoma. Given the inherent limitations of the included studies, future well-designed randomized controlled trials are required to confirm our findings.