Complications were less common with robot-assisted partial nephrectomy (RAPN) than with open partial nephrectomy (OPN) in a large study of patients with renal cancer.

RAPN was associated with a 61% decrease in intraoperative complications and a 71% decrease in overall complications in the IRON study.

Alessandro Larcher, MD, of San Raffaele Hospital and the Urological Research Institute in Milan, presented results from IRON during a live poster session at the virtual annual congress of the European Association of Urology.

The IRON study was performed in nine high-volume centers and involved 3,468 patients with renal cell cancer. Patients were recruited if they had a localized renal cell mass (cT1-2) with no nodal involvement or metastases. There were 2,405 patients who underwent RAPN and 1,063 who underwent OPN.

Intraoperative complications occurred in 5.7% of patients who underwent RAPN and in 9.3% of those who underwent OPN. Overall complications occurred in 33% and 18%, respectively (P < .001 for both).

“The complication profile was invariably in favor of robot-assisted surgery,” Dr. Larcher observed.

Patients who underwent RAPN had less estimated median blood loss (150 mL vs. 180 mL, P < .001) as well as lower rates of hemorrhagic complications (6.4% vs. 9%, P < .01) and urinary leakage (0.8% vs. 4.6%, P < .01).

The operative time was longer with RAPN than with OPN, at a median of 150 minutes and 120 minutes, respectively (P < .001). However, patients remained in the hospital for less time with RAPN than with OPN, at a median of 4 days and 6 days, respectively (P < .01).

RAPN was associated with fewer surgical complications than OPN according to the Clavien-Dindo system. Grade 2 or higher complications occurred in 12% and 20% of patients, respectively (P < .001). Grade 3 or higher complications occurred in 4% and 6.1%, respectively (P < .001).

“The benefit with respect to the complication risk reduction in the case of robot-assisted surgery was not affected by the tumor complexity, by the dimension of the mass, the comorbidities of the patients, or the baseline renal function,” Dr. Larcher said. “[T]he advantage after robot-assisted surgery is consistent regardless of all these features.”

Early renal function was better after OPN, but there was no significant difference between the two groups at 1 year of follow-up. The median ischemia time was 15 minutes with OPN and 16 minutes with RAPN (P < .001).

Postoperatively, the median estimated glomerular filtration rate was 78 mL/min/1.73m2 with OPN and 76 mL/min/1.73m2 with RAPN (P < .001). At 1 year, the median estimated glomerular filtration rate was 68 and 71 mL/min/1.73m2, respectively (P = .5).

Dr. Larcher noted that there was no difference between RAPN and OPN in terms of 5-year oncologic outcomes. Local recurrence occurred in 1.6% and 2.1% of patients, respectively (P = .06); systemic progression was seen in 1.8% and 4.5%, respectively (P = .5); and clinical progression was observed in 3.2% and 6.6%, respectively (P = .9).

“[IRON is] a really powerful study. It’s one of those studies that kind of has to be done,” said Ben Challacombe, MBBS, a consultant urological surgeon at Guy’s Hospital and St. Thomas’ Hospital in London who chaired the poster session during which these findings were presented.

Dr. Challacombe, who specializes in the treatment of kidney and prostatic disease using robotic surgery, noted that about 75% of procedures in the United Kingdom are now being performed with robotic assistance and queried what percentage of procedures should still be done by open surgery.

“I would turn it,” Dr. Larcher said. “What is the percentage of surgeons that should use one technique or the other?” In the IRON study, as well as other studies, surgical expertise, training, and center volumes were important.

“What the data are telling us is that those who are really confident in robotic surgeries can achieve even better outcomes, also in very complex cases,” Dr. Larcher said. “I think it’s not any longer dependent on the tumor factors. The answer to the question is only determined by human factors.”

The IRON study was supported by a grant from Intuitive. Dr. Larcher declared no conflicts of interest. Dr. Challacombe did not present any disclosures.

SOURCE: Larcher A et al. EAU20, Abstract 30. Eur Urol Open Sci 2020;19(Suppl 2):e142.