Mucinous Adenocarcinoma of the Endometrium Confers Increased Risk of Lymph Node Metastases.
Fernanda Musa, Brandi Adams, Kevin Holcomb, Edyta Pirog. Weill Cornell Medical College, New York, NY
Background: Mucinous adenocarcinoma of the endometrium (MUC) is a rare histological variant of endometrial carcinoma accounting for less than 10% of endometrial tumors. The tumor develops in a background of hyperplasia and mucinous metaplasia of the endometrium. Few studies have characterized its clinical behavior. The aim of this study is to compare the risk factors and clinical course of MUC relative to endometrioid adenocarcinoma.
Design: A case-control study was performed which included patients treated for endometrial cancer at the New York Hospital – Cornell Medical Center between 1996 and 2006. Mucinous adenocarcinoma was defined as tumor with more than 50% of mucinous-type epithelium. 41 cases of were identified. Each case was matched by age and histological grade with two controls of endometrioid histology. Cases and controls were compared with regard to known risk factors for endometrioid carcinoma and the extent of disease at diagnosis. Chi-square tests were used to compare proportions and student T-tests for the comparison of means. Multivariate regression was used to identify the independent predictors of lymph node metastases. Overall survival was calculated using the Kaplan-Meier method and compared with the Log-rank test. P< .05 was considered significant for all tests.
Results: No significant difference was found between cases and controls with regard to ethnicity, body mass index, history of diabetes mellitus, hypertension, prior hormone replacement, and tamoxifen use. Prior oral contraceptive use was significantly less common among women with MUC compared to controls (6.5% vs 32.3%, P= .01). No significant differences in myometrial invasion (MI) > 50% or the presence of lymph-vascular space invasion was found between cases and controls, however 17% of patients with MUC had lymph node metastases compared to 3% of controls (P= .01). Multivariate analysis controlling for both tumor grade and depth of MI identified mucinous histology as an independent predictor of lymph node metastasis (P =.02). Adjuvant radiation or chemotherapy was used in 60% of cases compared to 42% of controls (P =.05). No difference in recurrence or survival was identified between the two groups.
Conclusions: Mucinous adenocarcinoma of the endometrium is associated with an increased risk of lymph node metastases that is independent of tumor grade and depth of MI. Comprehensive surgical staging including retroperitoneal node dissection should be considered in all patients with this diagnosis.
Category: Gynecologic & Obstetrics
Wednesday, March 2, 2011 1:00 PM
Poster Session VI # 153, Wednesday Afternoon