Richard J. Santen, MD, professor of medicine, endocrinology and metabolism at the University of Virginia, gave the Plenary Joint Lecture at the Conjoint Meeting of the International Federation of Fertility Societies and the American Society for Reproductive Medicine and said the WHI study led by JoAnn Manson, MD, DrPH, should be commended for its concentration on absolute risk, rather than relative risk, but commented on the breakdown of risk per 10,000 women for one year of HT.
Most women take hormone therapy for 3, 4 or 5 years so if you express the risk per 1 year, you’re really underemphasizing the risk.
Santen and colleagues presented data from the WHI re-analysis and looked at 5 years of HT, focusing on women aged 50 to 59 years because this cohort would be making immediate decisions about HT.
The average age of the participants in the entire WHI study was 63 years, whereas the WHI re-analysis looked at the subset ages 50-59.
The 5-year data showed an increased risk of three women per 1,000 with estrogen plus progestin therapy (EPT), but a 2.5 per 1,000 risk reduction with estrogen alone, which Santen attributed to apoptosis if a breast cancer tumor had been deprived of estrogen for some time. In addition, Santen applied a previously published model that took the doubling time of breast cancer tumors into consideration, suggesting that only 6% of cancers seen in the WHI study were de novo tumors. The others were most likely growths of undetected tumors present at the start of the study.
Santen contends that hormone therapy does not cause breast cancer, it causes existing breast cancer to grow more rapidly.
Read the full article here:
Re-analysis of WHI data shows breast cancer growth, not de novo tumor formation, for 5 year EPT users
See also:
Prentice RL, Manson JE, Anderson GL, Lacroix AZ, Shumaker SA, Chlebowski RT, Howard BV, Stefanick ML, Jackson RD, Wactawski-Wende J, Rossouw JE. Women's Health Initiative View of Estrogen Avoidance and All-Cause Mortality. Am J Public Health. 2013 Dec;103(12):e2. doi: 10.2105/AJPH.2013.301604. Epub 2013 Oct 17.
Content created 18 November 2013