The Impact of the Relevant Factors as High-Complexity Tumors in Robot-Assisted Partial Nephrectomy

This study aims to determine the impact of the number of relevant factors for high-complexity tumors on perioperative outcomes of robot-assisted partial nephrectomy (RAPN).

The 308 patients who underwent RAPN for renal hilar, completely endophytic, or clinical T1b tumors were defined as the complex tumor group (CTG), and the other 752 were defined as the non-complex tumor group (NCTG). The CTG patients were further classified on the basis of their number of relevant factors for high-complexity tumors into the one-factor and multiple-factor subgroups. Perioperative outcomes were compared for each group.

The median times using the robotic system were 187 and 167 min (p = 0.0006), median warm ischemic times (WITs) were 24 and 20 min (p < 0.0001), Grade 3 or higher complication rates were 6.2% and 2.5% (p = 0.0038), median preserved renal function rates at 1 month postoperatively were 78.9% and 85.2% (p < 0.0001), and trifecta achievement rates were 55.2% and 76.9% (p < 0.0001), respectively. RFS was significantly worse in CTG than in NCTG (5-year RFS was 92.6% and 97.4%, respectively). In the one- and multiple-factor subgroups, the median times using the robotic system were 184 and 222 min (p = 0.0003), median WITs were 23 and 28 min (p = 0.0002), median preserved renal function rates at 1 month postoperatively were 80.1% and 73.1% (p = 0.0036), and trifecta achievement rates were 59.9% and 37.9% (p = 0.0014), respectively.

RAPN for high-complexity tumors may show different perioperative outcomes depending on the number of relevant factors. Recurrence appears to be more frequent in high-complexity tumors.