Lymphovascular space invasion and cervical stromal invasion are independent risk factors for nodal metastasis in endometrioid endometrial cancer

Aims: The purpose of this study was to investigate the potential roles of pathological variables in the prediction of nodal metastasis in women with endometrioid endometrial cancer (EC). Materials and Methods: Women who underwent surgery for endometrioid EC between 1995 and 2012 were retrospectively reviewed. Those who underwent prior neoadjuvant chemotherapy or radiotherapy and inadequate lymphadenectomy as well as those with nonendometrioid histology, synchronous cancers, International Federation of Gynecology and Obstetrics stage IV disease, gross uterine serosal and/or gross adnexal involvement were excluded. Lymph node dissemination was defined as occurring in the following circumstances: (i) when nodal metastasis with pelvic and/or para-aortic (P/PA) lymph node dissection (LND) was performed or (ii) when there was recurrence in the P/PA lymph nodes after a negative LND or when LND was not performed. Univariate and multivariate logistic regression models were used to identify the pathological predictors of lymphatic dissemination. Results: A total of 827 women with endometrioid EC were assessed; 516 (62.4%) of whom underwent P/PA LND and 205 (24.8%) underwent P LND. Sixty-seven (13%) women in the P/PA LND group and 5 (2.4%) in the P LND group had positive lymph nodes. Multivariate analysis confirmed cervical stromal invasion (OR 4.04, 95% CI 2.02-8.07 (P < 0.001)) and lymphovascular space invasion (LVSI) (OR 110.18, 95% CI 38.43-315.87 (P < 0.001)) as independent predictors of lymphatic dissemination. Conclusion: Cervical stromal invasion and LVSI are highly associated with LN metastasis. These markers may serve as a surrogate for nodal metastasis. © 2015 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.