Survival benefits of pelvic lymphadenectomy versus pelvic and para-aortic lymphadenectomy in patients with endometrial cancer: A meta-analysis

Abstract

Background: Despite that pelvic and para-aortic lymphadenectomy (PPaLND) is recommended as part of accurate surgical staging by International Federation of Gynecology and Obstetrics (FIGO) in endometrial cancer, the impact of para-aortic lymphadenectomy on survival remains controversial. The aim of this work is to evaluate the survival benefits or risks in endometrial cancer patients who underwent surgical staging with or without para-aortic lymphadenectomy using meta-analysis.

Methods: Literature search was undertaken using PubMed, Embase, and Cochrane Library databases for relevant articles published between January 1, 1990, and January 1, 2017, without language restriction. The primary outcome was overall survival (OS); progression-free survival (PFS)/recurrence-free survival (RFS)/disease-free survival (DFS)/disease-related survival (DRS) was also analyzed. Subgroup analysis and sensitivity analysis were conducted to investigate the source of heterogeneity. Quality assessments were performed by Newcastle-Ottawa Quality Assessment Scale (NOS). Publication bias was evaluated by using Begg and Egger tests. The hazard ratio (HR) was pooled with random-effects or fixed-effects model as appropriate.

Results: Eight studies with a total of 2793 patients were included. OS was significantly longer in PPaLND group than in pelvic lymphadenectomy (PLND) group for patients with endometrial cancer [HR 0.68; 95% confidence interval (CI) 0.55-0.84, P < .001, I = 12.2%]. Subgroup analysis by recurrence risk explored the same association in patients at intermediate- or high-risk (HR 0.52; 95% CI 0.39-0.69, P < .001, I = 41.4%), but not for low-risk patients (HR 0.48; 95% CI 0.21-1.08, P = .077, I = 0). PPaLND with systematic resection of all para-aortic nodes up to renal vein also improved PFS/RFS/DFS/DRS, compared with PLND (HR 0.52, 95% CI 0.37-0.72, P < .001, I = 0). No publication bias was observed among included studies.

Conclusion: PPaLND is associated with favorable survival outcomes in endometrial cancer patients with intermediate- or high-risk of recurrence compared with PLND, particularly with regards to OS. PPaLND with systematic resection of all para-aortic nodes up to renal vein also improve PFS compared with PLND. Further large-scale randomized clinical trials are required to validate our findings.

Figure 1

Articles searching flow chart.

Figure 2

Meta-analysis of PPaLND and PLND on OS in endometrial cancer. OS = overall survival, PLND = pelvic lymphadenectomy, PPaLND = pelvic and para-aortic lymphadenectomy.

Figure 3

Meta-analysis of PPaLND and PLND on OS in intermediate- or high-risk patients. OS = overall survival, PLND = pelvic lymphadenectomy, PPaLND = pelvic and para-aortic lymphadenectomy.

Figure 4

Meta-analysis of PPaLND and PLND on PFS/RFS/DFS/DRS in endometrial cancer. DFS = disease-free survival, DRS = disease-related survival, PFS = progression-free survival, PLND = pelvic lymphadenectomy, PPaLND = pelvic and para-aortic lymphadenectomy, RFS = recurrence-free survival.

Figure 5

Sensitivity analysis for testing HR for OS. HR = hazard ratio, OS = overall survival.

Figure 6

Funnel plots to evaluate publication bias of included studies for OS. OS = overall survival.