MedicalResearch: What is the background for this study?
Dr. Arem: In the United States, men are more likely to develop colorectal cancer (CRC) than women. In large prospective studies, researchers observed that women who reported taking menopausal hormone therapy (MHT) containing estrogen had a 30-40% lower risk of colorectal cancer, compared to women who did not report menopausal hormone therapy use, suggesting an anti-carcinogenic role for estrogen.
We investigated the relationship between estrogen exposure (hormonal and reproductive factors) in relation to survival (risk of death) among women diagnosed with colorectal cancer.
MedicalResearch: What are the main findings?
Dr. Arem: We found a 20% lower risk of death overall among women who reported current menopausal hormone therapy use at study entry (HR=0.79, 95% CI 0.66-0.94) and a 24% lower risk of death from colorectal cancer (0.76, 0.59-0.99), compared to women who reported never using menopausal hormone therapy.
Among women in our study, we observed no statistically significant associations for colorectal cancer mortality with oral contraceptive use, menarche age, age at first birth, parity, or menopausal age.
MedicalResearch: What should clinicians and patients take away from your report?
Dr. Arem: Our study was designed to investigate a mechanistic role for estrogen on carcinogenesis for research purposes. We do not expect these findings to influence clinical practice or behavior.
MedicalResearch: What recommendations do you have for future research as a result of this study?
Dr. Arem: Future studies should focus on the mechanisms by which exogenous estrogen exposure might affect tumor progression and colorectal cancer survival.
Dr. Hannah Arem Ph.D. M.H.S. Postdoctoral Fellow (2015). Postmenopausal Hormones Linked To Decreased Colon Cancer Risk