In Focus: Partial Nephrectomy: Open or Robotic?

The ROBOCOP II Study is the first randomised trial comparing robotic to open partial nephrectomy (RAPN vs OPN).(1) It was a single center open label trial performed in Germany and the primary outcome was to assess the feasibility of recruitment for a RCT by assessing the accrual rate. The authors reported a 65% recruitment rate and were able to randomise 50 patients  and met their primary outcome. This is in stark contrast with other similar studies which were terminated prematurely due to poor accrual, the CONVERT trial and the OPERA trial. The reason for success of this trial was the public insurance system in Germany, where most of the patients do not get to know the price of their treatment, thus the common perception, “the costlier the better”, prevents opting for RAPN. However, the authors also noted that only 1 patient opted out of the trial as he/she explicitly wanted OPN, whereas the majority of the patients who opted out the trial did so to choose RAPN. Although the trial the was not powered for oncological outcomes, it is the only RCT on this topic and thus merits discussion. The authors reported a similar trifecta rate and oncological outcomes in the two arms, whereas the warm ischemia time was shorter in the OPN arm by 6.7min (8.7min vs 15.4min) as was the total operative time by 18min (112min vs 130min). As expected, the blood loss (149ml vs 361ml) and the need of opioid analgesia was lower in the RAPN arm. Of note were the complications, although the major complication rate was similar in the two arms (3 in RAPN & 2 in OPN), none of the patients in the rapN arm had a minor complication, whereas 44% of the patients in the OPN had minor complications. The common/relevant minor complications were blood transfusion, DVT, wound infection and chest related complications. Besides, the length of stay was also shorter in the RAPN arm, but this did not reach statistical significance. Thus the findings of this trial echoes what has been reported by various other non-randomised trials and emphasis the benefits of each approach and establishes the safety and efficacy of both the approaches.