ESOU 2022: Indication and Results of Robotic Partial Nephrectomy for T1/T2 Tumours

(UroToday.com) In a podium presentation in the ESU-ESOU-ERUS session at the 19^th Meeting of the EAU Section of Oncological Urology, Dr. Andrea Minervini presented on the role of robotic partial nephrectomy for T1 and T1 renal tumors.

To begin, he highlighted a historical review of the evolution of management of localized renal masses in terms of treatment indications, candidates, and goals. Dating back only 20 years, radical nephrectomy was widely considered the gold standard for treatment of renal cell carcinoma (RCC), with partial nephrectomy restricted to imperative indications. In 2006, partial nephrectomy was recognized as a valid treatment option for patients with small renal masses (cT1a RCC). As of 2017, partial nephrectomy was recommended to be offered to patients with T1 tumors on the basis of a low-grade recommenddations.

Currently, as of 2021, guidelines recommend partial nephrectomy should be offered to all patients with T1 tumors with a strong recommendation. Additionally, the 2021 EAU guidelines strongly recommend that urologists should not perform a minimally invasive radical nephrectomy for patients with T1 tumors in whom partial nephrectomy is feasible by any surgical approach, including open.

The rationale for partial nephrectomy has grown, first on the basis of basis of comparable oncologic efficacy. In a number of series with long-term follow-up, partial nephrectomy demonstrates comparable local and distant recurrence, and cancer specific survival to radical nephrectomy. However, beyond oncologic equivalence, the rationale for partial nephrectomy rests, as Dr. Minervini pointed out, on lower associated rates renal dysfunction as well as attributable cardiovascular events and associated mortality. Referring to a “virtuous funnel” of partial nephrectomy with comparable oncologic efficacy, better renal functional outcomes, and lower rates of cardiovascular disease, he emphasized that partial nephrectomy may actually improve overall survival. Systematic reviews of observational data have demonstrated this though the randomized EORTC trial did not.

Compared to open surgery, he emphasized that recent data has shown that robotic assisted partial nephrectomy was associated with a significantly less blood loss, lower rates of serious (Clavien Dindo grade 2 or greater) complications, shorter warm ischemia time, decreased risk of post-operative acute kidney injury (by half), a lower risk of early renal functional impairment, and a higher probability of a trifecta outcome. Even among patients with highly complex tumors, as evaluated in the RECORD2 and SIB project, patients with complex tumors defined as PADUA scores of 10 or higher, a robotic surgical approach was found to be protective of surgical complications as well as predictive of a trifecta rate (70% vs 43%, compared to open surgery). In the SIB analysis, even after multivariable adjustment, robotic surgery was associated with an increased rate of the trifecta outcome.

This increasing awareness of the benefits of nephron sparing and robotic surgical approaches have now led to the expansion of this approach beyond patients with cT1 tumors to include those with cT2 disease. This is advocated in the most recent 2021 EAU guidelines which encourage partial nephrectomy in the case of T2 tumors where technically feasible. Citing data from the multi-center ROSULA collaborative, Dr. Minervini emphasized that robotic partial nephrectomy can be safely performed for cT2 renal masses with acceptable morbidity and without compromising oncologic control. Compared to laparoscopic radical nephrectomy, robotic partial nephrectomy did not have an increased recurrence rate but was associated with improved renal functional outcomes.

Dr. Minervini highlighted that a large tumor size is not necessarily associated with a more difficult excision or renorrhaphy, particularly when there are favourable tumor characteristics including an exophytic tumor location, minimal proximity to the sinus, and a large volume of health parenchyma.

Taking this concept further, he suggested that for patients with cT1-2 tumors who are pathologically upstaged to pT3a disease, the type of intervention (radical vs partial nephrectomy) is not associated with recurrence rates or overall survival. However, patients who underwent partial nephrectomy had less change in renal function and were less likely to have de novo renal dysfunction. Emphasizing this further, he highlighted that tumor dimension should not be considered a surrogate of tumor aggressiveness. Instead, in the elective indication, partial nephrectomy should be considered the treatment of preference where it does not compromise cancer control. He highlighted that radical nephrectomy should be preferred in patients with evidence of infiltrative tumor growth, multiple intrarenal bulging consistent with intrarenal venous thrombosis, or urinary collecting system involvement.

Moving forward, ongoing work will add to the body of evidence supporting partial nephrectomy and, in his view, “hopefully” lead to a changing of EAU recommendations to favour robotic nephron-sparing surgery. In closing, he highlighted the prospective global iRECORd register which, to date, includes 50 centers.