Prognostic significance of systematic retroperitoneal lymphadenectomy in patients with epithelial ovarian cancer: a Meta-analysis

Abstract

Objective: To investigate the survival impact of systematic retroperitoneal lymphadenectomy (SL) and unsystematic lymphadenectomy (USL) in patients with epithelial ovarian cancer. Methods: Randomized control trial (RCT) and observational studies about the effects of SL and USL on patients with epithelial ovarian cancer were searched in major online databases including PubMed, Embase, Web of Science, and Cochrane Library. The literature search was performed up to January 2016. The results were analyzed using RevMan 5.0 software. Results: Totally 14 studies including 1 634 patients in SL group and 1 719 patients in USL group were enrolled. Three of the 14 studies were RCTs, and the other 11 were observational studies. Meta analysis showed that SL was a favorable factor for 5-year overall survival rate (5-OS) compared with USL[RR=0.89, 95% CI (0.81, 0.97), P=0.007]. However, the efficacy of SL on increased 5-OS could not be determined in all type of studies owing to the result of RCTs[RR=0.99, 95% CI (0.85, 1.15), P=0.90], whereas SL improved 5-OS of patients in observational studies[RR=0.84, 95% CI (0.76, 0.93), P=0.001]. Moreover, SL increased 5-OS in patients with early stage (FIGO Ⅰ-Ⅱ) disease comparing with USL[RR=0.78, 95% CI (0.61, 0.99), P=0.04], as well as it could improve 5-OS statistically in advanced stage (FIGO Ⅲ-Ⅳ) disease[RR=0.90, 95% CI (0.82, 0.99), P=0.03]. But analysis on patients with optimal debulking surgery showed that SL could not improve 5-OS of these patients, regardless of early stage[RR=0.71, 95% CI (0.43, 1.17), P=0.18]or advanced stage[RR=1.01, 95% CI (0.90, 1.14), P=0.86]. Conclusions: The impact of SL on the survival of patients with epithelial ovarian cancer is still extremely controversial, which requires more relevant RCTs. In patients with optimal debulking surgery, SL could hardly improve the survival.