January 31, 2011 — Breast cancer risk associated with combination hormone replacement therapy (HRT) is greater if the therapy is started soon after menopause, according to the results of the observational Million Women Study conducted in the United Kingdom...The other question that remains unanswered is what are the impact of other formulations of estrogen and progesteron supplementation for HRT.
...Among current users of estrogen–progestin formulations, the relative risks for breast cancer were greater if use began less than 5 years after menopause (relative risk [RR], 2.04; 95% confidence interval [CI], 1.95 to 2.14) than if it began 5 years or more after menopause (RR, 1.53; 95% CI, 1.38 to 1.70)...
...Overall, for women who used combination HRT, compared with control subjects, there was a 39% increase in the relative risk of developing breast cancer in the Million Women Study and a 26% increase in the WHI trial, which the editorialists call "consistent" findings...
"The question of the effect of estrogen-only formulation use on breast cancer risk in postmenopausal women, even with longer-term hormone use, still stands unanswered," write the editorialists.
J Natl Cancer Inst. Published online January 28, 2011. Full text, Editorial
- Estrace & Prometrium
- "bioidentical" hormones (compounded)
Interestingly, here is an article that was published Feb '10 (epublished about 6 months ago) in the Gynecological Endocrinology Journal. This article looks at women who were administered natural estrogen plus progesterone with or without DHEA or testosterone. It is obviously not a long-term study looking at breast cancer incidence outcomes, but leaves one thinking "what if" and what would be the outcome should this be readily explored. Ethics may come into the equation, however, given the other mainstream evidence that has been published.
"Mental symptoms experienced upon presentation improved in 90% of the patients. Sixty percent of the patients, who had gained weight during menopause, lost an average of 14.8 lbs [SD 11.98 lbs]. Complications described with traditional HRT did not develop in this group of patients."