Impact of lymphadenectomy in uterine endometrioid carcinoma.

ABSTRACT

AIMS: To investigate the role of lymphadenectomy in uterine endometrioid carcinoma based on the 2009 FIGO staging system. METHODS: Using an institution-maintained cancer registry database, all patients who were treated surgically for endometrial cancer from 1991 to 2008 in two medical centers were analyzed. Kaplan-Meier and Cox proportional hazards methods were used to determine the role of lymphadenectomy. RESULTS: From 961 women with uterine endometrioid carcinoma, 680 underwent lymphadenectomy and 281 did not. Young age, early-stage disease, low-grade tumor, and lymphadenectomy were favorable independent prognostic factors. The five-year disease-specific survival (DSS) of stages IA, IB, II, and III, and the two-year DSS of stage IV patients who underwent lymphadenectomy were 97.8%, 88.3%, 91.5%, 70.5%, and 32.1%, respectively, compared to 98.7%, 70.0%, 73.3%, 42.9%, and 16.6% in those without lymphadenectomy (p > 0.05 for stage IA; p < 0.01 for stages IB-IV, log-rank test). In high-risk patients (i.e., poorly-differentiated, outer-half myometrial invasion, and stages II-IV), more extensive lymph node resection was associated with an improved five-year DSS, from 71.3% (1-10 nodes removed) and 85.3% (11-20 nodes removed) to 86.8% (>20 nodes removed) (p = 0.02, log-rank test). For stage IIIC-IV patients with nodal metastasis, the extent of node resection also significantly improved the five-year DSS, from 34.4% (1-10 nodes removed) and 62.4% (11-20 nodes removed) to 79.6% (>20 nodes removed) (p = 0.04, log-rank test). CONCLUSIONS: Lymphadenectomy improves the survival of patients with uterine endometrioid carcinoma stage IB to stage IV. The extent of lymphadenectomy also improves the survival of high-risk patients and those with nodal disease.