V10-01: Robot-assisted partial nephrectomy: techniques and outcomes from the Transatlantic RObotic NEphron-sparing Surgery (TRONES) Study Group
Robot-assisted partial nephrectomy (RAPN) is considered a feasible minimally invasive alternative to open partial nephrectomy (OPN) for the surgical treatment of renal tumors. The objective of the study is to provide further evidence supporting the effectiveness of RAPN in tertiary care centers and to describe the evolution of RAPN based technical improvements.
The Transatlantic Robotic Nephron-sparing Surgery (TRoNeS) study group prospectively collected data from 635 patients subjected to RAPN between 2010 and 2016 at three high volume tertiary care centers. All patients underwent either preoperative CT-scan or MRI to anatomically define the renal masses.
Of 635 patients, 399 (62.8%) were males. Mean patient age was 60.7 yrs and mean preoperative tumor size was 33 mm, with 324 (51.0%) of tumors being right sided. According to the PADUA score, 202 (31.8%) patients had a low complexity tumor, while 235 (37.0%) and 198 (31.2%) were of intermediate and high complexity, respectively. In the majority of patients, a transperitoneal approach was used (n=447; 70.4%). Mean operative time was 156.3 minutes and mean estimated blood loss was 171 mL. Main artery clamping was performed in 506 (79.7%) patients, as compared to 107 (16.9%) undergoing selective clamping and 22 (3.4%) individuals were a "zero-ischemia" RAPN was performed. Mean WIT was 16.3 minutes; 141 (22.2%) patients experienced a WIT >20 minutes. Malignant tumors were observed in 473 (74.5%) individuals and surgical margins were positive in 24 (3.8%) patients. Overall, 25 (3.9%) patients experienced a significant (Clavien-Dindo >2) complication. No statistically significant differences between preoperative and postoperative creatinine values were observed (p=0.823). Optimal surgical outcomes defined according to the MIC score were achieved in 459 (72.3%) individuals. At a mean follow-up of 26 months, 2 local and 2 distant recurrences of the disease were observed. Finally, in multivariable LRMs patients with highly complex tumors according to the PADUA score experienced a 3.2-fold higher risk of not achieving optimal surgical outcomes relative to patients with low-complexity tumors (p=0.001)
The current study provides further evidences supporting the role of RAPN as a viable and effective minimally-invasive alternative to OPN in the treatment of clinically-localized renal tumors. Despite surgical experience and technological improvements, tumor complexity still represents an independent predictor of optimal surgical outcomes.