Marin medical researchers’ suspicions that Marin women’s use of estrogen and progesterone was linked to the county’s high incidence of breast cancer – reported last fall – have been validated.The first major cancer research results from the Marin Women’s Study were published last week in the online medical journal BioMed Central, and they showed that a sharp reduction in the use of combined estrogen and progesterone hormone therapy was followed by a significant change in Marin women’s breast cancer rates.
Use of this combined therapy declined among Marin County women age 50 and older from 21.2 percent in 1998 to 6.7 percent in 2006-07. This sharp decline in combined hormone use was followed by a 33.4 percent reduction in invasive breast cancer between 2001 and 2004.
The Marin Women’s Study, launched in 2006, is an ambitious effort to collect blood, saliva and personal information from thousands of Marin women. When women seek a mammogram, they are asked to donate biological specimens and complete a 20-page questionnaire. So far, 14,000 Marin women have participated. The study is a joint project of the county of Marin, the Buck Institute for Age Research, the Northern California Cancer Center, Zero Breast Cancer and others.
Rochelle Ereman, an epidemiologist with the county of Marin and the principal investigator at the Marin Women’s Study, said she and other researchers have just begun to tap the riches of the data collected.
“So now, we have all 14,000 surveys together in one data base, and we’re looking at all the other risk factors that we have in the data base,” Ereman said.