Fewer Complications With Robotic Nephrectomy in Complex Kidney Tumors

Robotic-assisted partial nephrectomy (RAPN) led to a lower rate of complications compared with open partial nephrectomy (OPN) in patients with intermediate- or high-complexity kidney tumors, the randomized OpeRa trial found.

Among over 200 patients, 36.6% of those who underwent RAPN had a postoperative complication of any kind within 30 days — the trial’s primary endpoint — compared with 46.1% of those who underwent OPN, reported Marc-Oliver Grimm, MD, of University Hospital in Jena, Germany, during a presentation at the European Association of Urology (EAU) annual congress.

While that difference was “close to the 10% we expected,” Grimm said, he acknowledged the trial was not statistically powered to show a significant difference in its primary endpoint, since it was stopped prematurely due to slow enrollment.

“The main difference in favor of the robotic arm was due to low-grade complications,” he noted. “High-grade complications were, in general, infrequent.”

Grade I and II complications were experienced by 38.2% and 25.0% of patients in the OPN and RAPN arms, respectively, while patients in the RAPN arm experienced more grade III and IV complications — 11.7% versus 7.9%.

EAU discussant Alberto Breda, MD, of Fundació Puigvert in Barcelona, noted that while patients in the OPN and RAPN arms had comparable RENAL nephrectomy scores (mean scores of 8.39 and 8.36, respectively) at baseline, a higher percentage of patients in the RAPN arm had scores of 10 or higher (16.2% vs 13.3%).

“That may justify this increase in this kind of complication, which were mainly AV-fistula and urine leakage,” he said.

Breda also pointed out that not every surgeon in the study was highly experienced, nor were all the centers in the study high-volume centers. “And we know from the literature that there is a direct correlation between volume and complication rate. The more you do, the fewer complications you have.”

Grimm and colleagues also noted that significantly fewer patients in the RAPN group experienced postoperative complications deemed related to the procedure (23.2% vs 37.1% of the OPN group), and these patients were discharged from the hospital a median of 1 day earlier. Higher patient-reported quality-of-recovery scores were also seen with RAPN, with significant improvement seen at postoperative day 3.

However, there was a significantly longer operative time with robotic surgery (167 vs 122 minutes), as well as higher readmission (8.5% vs 4.4%) and reoperation (7.7% vs 4.4%) rates.

There were no differences in intraoperative adverse events, transfusions, or estimated blood loss between the two groups.

Grimm pointed out that the trial represents a real-world example of the challenges associated with conducting a randomized controlled trial in this setting. In order to demonstrate the trial’s primary endpoint, the investigators aimed to enroll 606 patients. Grimm said that he and his colleagues fell far short of that mark for several reasons:

• Many centers were unwilling to randomize patients, resulting in just 12 centers participating instead of the 20 planned
• There were not enough participating surgeons with the required experience
• Lack of equipoise
• The COVID-19 pandemic

Another challenge the investigators faced was the degree to which participants preferred the robotic surgery approach. Of the 123 patients in the RAPN cohort, just two withdrew from the trial after randomization, while 23 of the 117 patients assigned to OPN withdrew their consent.

“That’s the reality nowadays, and we need to face this,” Breda said.

For this study, Grimm and colleagues included 240 patients from 12 centers. Baseline characteristics were generally similar between the groups. Mean age was 63.1 in the OPN group and 61.7 in the RAPN group. Of note, 37.8% of patients in the OPN group had a BMI of 30 or higher compared with 28.2% of the RAPN group. The OPN group also included more patients taking anticoagulants (36.0% vs 24.8%).