Abstract
BACKGROUND: The value of the retroperitoneal (R-RAPN) compared with the conventional transperitoneal (T-RAPN) approach in robot-assisted partial nephrectomy has not been finally clarified. The current work's objective was to prospectively investigate R-RAPN versus T-RAPN. METHODS: The study was designed as a prospective, controlled, non-randomized study with a non-inferiority design. The primary endpoint was Trifecta achievement. The sample size calculation required 141 T-RAPN and 94 R-RAPN. RESULTS: When the recruitment target of 141 was reached in the T-RAPN arm, only 34 R-RAPN had been performed, so the study was terminated early. Trifecta as the main outcome parameter was achieved in 82% of the R-RAPN and 76% of the T-RAPN groups, so no sign for inferiority could be detected (p = 0.6). CONCLUSIONS: In this prospective study, there was no evidence of inferiority of R-RAPN compared to T-RAPN for the Trifecta endpoint. R-RAPN may be an individually advantageous alternative to T-RAPN for selected patients. TRIAL REGISTRATION: The study was registered in the German Clinical Trials Register (DRKS00028619).