Risk Factors for Lymph Node Metastasis among Lymphovascular Space Invasion-Positive Women with Endometrioid Endometrial Cancer Clinically Confined to the Uterus

INTRODUCTION: We aimed to assess risk factors for lymph node (LN) metastasis among lymphovascular space invasion(LVSI)-positive women with pure endometrioid endometrial cancer (EC) clinically confined to the uterus. METHODS: Medical records of women who underwent primary surgery for EC between 2007 and 2016 at either of 2 gynecological oncology centers were retrospectively reviewed. Patient data were analyzed with respect to LN involvement, and predictive factors for LN metastasis were investigated. RESULTS: 280 patients with surgically staged endometrioid-type EC with LVSI were identified. LN involvement was detected in 88 patients (31.4%) with a systematic LN dissection. In multivariate analysis, elevated baseline serum CA 125 levels, deep myometrial invasion (MMI), adnexal involvement and positive peritoneal cytology were found to be independent risk factors for LN metastasis. In women without deep MMI and elevated baseline serum CA 125 levels, the rate of LN metastasis was 19%. The presence of solely deep MMI increased this probability up to 29.1%. The rate of LN metastasis was found to be 46.8% for women with both deep MMI and elevated baseline serum CA 125 levels. CONCLUSION: These findings may be useful in the decision-making process for LVSI-positive women who are unstaged.