Comparison of outcomes between laparoscopic and robot-assisted partial nephrectomy for complex renal tumors: RENAL score ≥7 or maximum tumor size >4 cm

We reviewed current studies and performed a meta-analysis to compare outcomes between laparoscopic partial nephrectomy (LPN) and robot-assisted partial nephrectomy (RAPN) treating complex renal tumors (RENAL score ≥7 or maximum clinical tumor size >4 cm).

Using the databases of PubMed, Embase, and the Cochrane Library, a comprehensive literature search was performed in April, 2020. Pooled odds ratios (ORs) or weighted mean differences (WMDs) with 95% confidence intervals (CIs) were calculated using fixed-effect or random-effect model. Publication bias was evaluated by funnel plots.

Ten observational studies including 5193 patients (LPN: 1574; RAPN: 3619) were included. There was no significant difference between the two groups regarding conversion to open (P=0.07) surgery, all complications (P=0.12), grade 1-2 complications (P=0.10), grade 3-5 complications (P=0.93), operative time (P=0.94), estimated blood loss (P=0.17). Patients undergoing LPN had a significant higher rate of conversion to radical (OR=4.33; 95% CI: 2.01-9.33; P<0.001), a longer ischemia time (IT, P<0.001; WMD=3.02 min; 95% CI: 1.67 to 4.36), a longer length of stay (LOS, P<0.001; WMD=0.67 days; 95% CI: 0.35 to 0.99), a lower rate of positive surgical margin (P=0.03; OR=0.71; 95% CI: 0.53 to 0.96), a greater eGFR decline (P<0.001; WMD=2.41 mL/min/1.73 m²; 95% CI: 1.22 to 3.60), a higher rate of CKD upstaging (P<0.001; OR=2.44; 95% CI: 1.54 to 3.87). No obvious publication bias was observed.

For complex renal tumors, RAPN is more favorable than LPN in terms of lower rate of conversion to radical surgery, shorter IT, shorter LOS, less eGFR decline, and lower rate of CKD upstaging. Methodological limitations of observational studies should be taken into account in interpreting these results.