Lymphovascular space invasion and positive pelvic lymph nodes are independent risk factors for para-aortic nodal metastasis in endometrioid endometrial cancer

ObjectivePara-aortic lymph node dissemination in endometrioid endometrial cancer is uncommon, and systematic para-aortic lymph node dissection increases morbidity. The purpose of this study was to identify a subgroup of endometrioid endometrial cancer patients who did not require para-aortic lymphadenectomy.Study designAll patients who had undergone surgery for endometrioid endometrial cancer between 1 January 1995 and 31 December 2012 were retrospectively reviewed. Patients with higher risk factors for nodal metastasis and inadequate lymphadenectomy were excluded. Para-aortic lymph node dissemination was defined as nodal metastasis when pelvic and para-aortic lymph node dissection was performed, when para-aortic lymph node recurrence occurred after negative para-aortic lymph node dissection or when para-aortic lymph node dissection was not performed. Multivariate logistic regression models were used to identify the pathological features as predictors for para-aortic lymphatic dissemination.ResultsA total of 827 patients were assessed, 516 (62.4%) of whom underwent pelvic and para-aortic lymph node dissection. Sixty-seven (13%) patients (37 with only pelvic, 26 with pelvic and para-aortic, and 4 with only para-aortic metastasis) had positive lymph nodes in the pelvic and para-aortic lymph node dissection group. Multivariate analysis confirmed positive pelvic nodes (odds ratio 20.58; p < 0.001) and lymphovascular space invasion (odds ratio 8.10; p = 0.022) as independent predictors of para-aortic lymphatic dissemination. When these two factors were absent (in 83% of patients), the predicted probability of para-aortic lymph node metastasis was 0.1%.ConclusionPositive pelvic nodes and lymphovascular space invasion are highly associated with para-aortic lymph node metastasis. These markers may be useful for identifying those patients who require para-aortic lymph node dissection.