Partial nephrectomy versus radical nephrectomy for large (≥ 7 cm) renal tumors: A systematic review and meta-analysis

We conducted a meta-analysis to evaluate the efficiency and safety of partial nephrectomy (PN) compared with radical nephrectomy (RN) for large (≥7 cm) renal tumors. A comprehensive literature search with no restrictions on language or region was conducted from August up to October in 2018 in the electronic databases of PubMed, EMBASE, the Cochrane Library, and Scopus. Studies meeting the inclusion criteria were subjected to a systematic review and cumulative meta-analysis to assess the oncological, functional, and perioperative outcomes of PN compared with RN for large renal tumors. Sensitivity analyses were performed by repeating the original meta-analyses with exclusion of the lowest-weighted or lowest-scored study. Thirteen retrospective studies including 2906 patients (PN: 1172; RN: 1734) were included in our analyses. The pooled hazard ratio (HR) of overall survival (OS) indicated significant differences between the PN and RN groups (HR: 0.76; p = 0.001), although no significant difference was observed between the two groups in terms of cancer-specific survival (CSS; HR: 0.91; p = 0.51). The pooled eGFR decrease was significantly lower in the PN group than that in the RN group (mean difference (MD): 11.59; p < 0.001). PN was associated with longer operative time and more estimated blood loss (MD: 65.33 min, p < 0.001 and MD: 97.83 ml, p < 0.001, respectively). Pooled odds ratios (ORs) revealed that, compared with RN, PN is associated with a significantly higher risk of low-grade and high-grade (OR: 1.59, p = 0.01 and OR: 7.35, p < 0.001, respectively) surgical complications. No statistical significances were changed in sensitivity analyses on all outcome variables, except for that on the low-grade complication when excluding the lowest-scored study. All results were pooled using the fixed-effects model due to the nil or low heterogeneity. No obvious publication bias was screened about reporting OS. In conclusion, while PN for large (≥7 cm) renal tumors is associated with better OS compared with RN, these methods show a similar CSS. However, the advantages of PN, a more involved procedure than RN, in preserving renal function are accompanied by a higher risk of surgical complications. Large-sample and well-designed randomized controlled trials with extensive follow up are needed to confirm and update our conclusions.