Prospective cohort of pre-diagnosis hormone exposure and post-diagnosis sex hormone levels with survival outcomes: Alberta Endometrial Cancer Cohort Study.

Purpose: To examine the associations between pre-diagnosis exogenous hormone exposure and endogenous sex hormone levels shortly after diagnosis with survival outcomes in endometrial cancer survivors. Methods: In this population-based cohort, females with endometrial cancer were followed from diagnosis to death or January 27, 2022. History of hormone exposure pre-diagnosis and sex-hormone levels shortly after diagnosis were obtained. The associations between hormone exposure and sex-hormone levels with disease-free survival (DFS) and overall survival (OS) were estimated using Cox proportional hazards regression by multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Results: During a median 16.9 years of follow-up (IQR = 15.5-18.1 years), 152 of the 540 participants had a recurrence and/or died. There were no statistically significant associations between exposure to hormonal contraception or menopausal hormone therapy before diagnosis and DFS or OS. Higher estrone levels post-diagnosis were associated with lower DFS (HR 1.56, 95% CI 1.04-2.34) and lower OS (HR 1.76, 95% CI 1.15-2.72). Lower DFS was also observed with higher estradiol levels (HR 1.56, 95% CI 1.02-2.41). Conclusion: There were no associations between pre-diagnosis hormonal contraception or menopausal hormone therapy use and endometrial cancer survival in our study. Endometrial cancer survivors with higher estrogen levels shortly after diagnosis had lower DFS and OS. Further research is needed to confirm these findings.