Objectives: The objective was to analyze the effect of various histopathologic characteristics on prognosis in surgical stage I (node-negative) endometrial carcinoma.
Methods: During a 10-year period, 229 patients with stage I epithelial (all subtypes) endometrial cancer had hysterectomy and node dissection. Mean number of nodes harvested was 16.2 pelvic and 5.7 paraaortic. Median follow-up was 83 months. Sixty-seven patients (29%) received adjuvant radiotherapy.
Results: Five-year disease-related survival (DRS) was 95%, and 5-year relapse-free survival (RFS) 91%. We observed 7 (3%) isolated vaginal recurrences, 14 (6%) distant failures, and 1 (0.4%) simultaneous recurrence at both regional (pelvic sidewall) and distant sites. Only 1 of 7 patients (14%) with vaginal failure died of the disease (median follow-up of censored patients after failure was 110 months), compared with 10 of the 15 patients (67%) with distant failure. By univariate analysis, myometrial invasion (MI) >or= 66%, nonendometrioid histology, lymphovascular invasion, absence of associated hyperplasia, and tumor diameter >2 cm were significant predictors of poor prognosis with distant failure (P <or= 0.05). Cox regression analysis identified MI >or= 66% as the only independent predictor of DRS (P < 0.001, relative risk [RR] = 12.44), RFS (P < 0.001, RR = 8.67), and distant failure (P < 0.001, RR = 24.89). Only 2% of patients with MI < 66% had distant failure and died of the disease at 5 years, compared with a 29% 5-year distant failure rate and a 22% 5-year death rate among patients with MI >or= 66%.
Conclusion: Stage I (negative nodes) endometrial cancer patients with MI >or= 66% are at significant risk for distant failure and death and should be considered candidates for new randomized trials of adjuvant systemic therapy.