Systematic lymphadenectomy in early-stage endometrial cancer: a systematic review of the literature with meta-analysis

Background: The value of systematic lymphadenectomy (SL) in the treatment of early endometrial cancer (ECC) is still being debated. The purpose of the present study was to assess the benefit of SL for ECC by performing a systematic review of the published literatures. Methods: Systematic research was performed on Pubmed Database, Embase, Medline, Web of Science and CENTRAL for studies from 2003 January to 2015 January. Firstly, the search was limited to clinical trials concerning the surgical treatments of endometrial cancer patients which were written in English. Then, we included articles according the following criteria: 1) content of included study: comparison between SL group and no SL group; 2) ECC: stage I or II endometrial cancer according the International Federation of Gynecology and Obstetrics (FIGO) staging system in 1998 or 2009; 3) definition of SL versus no SL: removal of ≥10 lymph nodes or pelvic lymphadenectomy versus removal of versus <10 lymph nodes or pelvic and para-aortic lymphadenectomy. Methodological quality was assessed with the Jadad scale. Result: Eight studies were eligible for our analysis (including three randomized controlled trials and five observational studies), which included 13892 clinically ECC patients. On one hand, the results indicated that there was obvious difference between SL and no SL group in 5 year survival rate for ECC patients with high risk of lymph node metastasis (LNM) (OR 0.42, 95% CI, 0.26 to 0.68; P =0.0004). However, there was no statistical difference between SL and no SL group in 5 year survival rate for all ECC patients (OR 0.85, 95% CI, 0.60 to 1.21; P =0.37) and ECC patients with low risk of LNM (OR 0.73, 95% CI, 0.38 to 1.73; P =0.32). On the other hand, SL group has a higher incidence of long-term complications than no SL group (P<0.05). Conclusion: The present systematic review indicates that SL may improve 5 year survival rate for ECC patients with high risk of LNM, while risking then of long term complications.