All-cause mortality in young women with endometrial cancer receiving progesterone therapy.

Background: Uterine-preserving therapy with progesterone may be used in young women with endometrial cancer who desire fertility preservation. Such therapy delays definitive treatment with hysterectomy.

Objective: We examined the use and safety of progestational therapy in young women with endometrial cancer. The primary outcome of the analysis was overall survival.

Study Design: We identified women ≤49 years of age with stage I endometrial cancer in the National Cancer Database from 2004 through 2014. Women treated with hormonal therapy with or without hysterectomy were compared to women treated with hysterectomy. After propensity score weighting, overall survival was examined using proportional hazards models.

Results: A total of 23,231 patients, including 872 (3.8%) women treated with hormonal therapy were identified. Use of hormonal therapy was 2.4% (95% confidence interval, 1.8-3.3%) in 2004 and increased over time to 5.9% (95% confidence interval, 5.0-6.9%) by 2014 (P < .0001). Use of hormonal therapy decreased with older age, higher substage, and increasing grade. Black women were more likely to receive hormonal therapy while Medicaid recipients were less likely to receive hormonal therapy. The 5-year survival for patients treated with hormonal therapy was 96.4% (95% confidence interval, 94.3-98.0%) compared to 97.2% (95% confidence interval, 96.9-97.4%) for hysterectomy. In a multivariable model, women treated with hormonal therapy were 92% (hazard ratio, 1.92; 95% confidence interval, 1.15-3.19) more likely to die compared to women who underwent primary hysterectomy. When stratified by stage, hormonal therapy was associated with increased mortality in women with stage IB and I-not otherwise specified tumors but not for stage IA neoplasms.

Conclusion: Use of progestational therapy is increasing. Its use was associated with decreased survival, particularly in women with stage IB tumors.