The prognostic significance of aortic lymph node metastasis in endometrial cancer: Potential implications for selective aortic lymph node assessment.

ABSTRACT

OBJECTIVES: To evaluate the prognostic impact of aortic vs. pelvic lymph node (LN) metastasis among women with endometrial cancer (EC). METHODS: Using data from the SEER 18 Registries we identified 3650 women with LN positive (stage IIIC) EC. We used Kaplan-Meier curves and log-rank tests to compare mortality between women with stage IIIC1 and IIIC2 disease. We used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between stage III sub-stage (IIIC1 vs. IIIC2) and survival. RESULTS: Endometrioid tumors were more common among women with stage IIIC1 than IIIC2 tumors (62.5% vs. 54.3%) while, non-endometrioid histologies were more common among stage IIIC2. In the multivariable model, stage IIIC2 was associated with higher all-cause (HR = 1.44, 95% CI = 1.22-1.69) and EC-specific mortality (HR = 1.49, 95% CI = 1.25-1.77) compared with IIIC1. Women with non-endometrioid EC had poor survival, in particular, women with carcinosarcomas had higher EC-specific mortality compared to women with endometrioid EC (HR = 3.32, 95% CI = 2.71-4.07). When stratifying women according to substage, older age and non-endometrioid histology were associated with higher EC-specific mortality. Compared to women with a pelvic-only LN dissection, women with pelvic and aortic dissections had lower all-cause (HR = 0.74, 95% CI = 0.63-0.88) and EC-specific (HR = 0.79, 95% CI = 0.66-0.95) mortality. CONCLUSION: Women with aortic LN positive EC are more likely to die from their disease. Older women and non-endometrioid histologies are more likely to have aortic LN involvement. Compared to women with a pelvic-only LN dissection, women with pelvic and aortic dissections had lower EC mortality.