That therapy, a combination of estrogen and progestins, can increase the incidence of breast cancer.Researcher now have 2004 data and say the effect of women discontinuing the hormone therapy is less likely to be an anomaly. If rates had gone up again, it would have meant that their hypothesis was incorrect.
Overall, in 2003 and 2004, there were nearly 10 percent fewer breast cancer cases than expected. It is the first substantial drop in breast cancer incidence in more than a quarter century. And it involved women age 50 and older, not younger women, and nearly all the decline was in the common type of breast cancer, fed by estrogen, the so-called estrogen-receptor-positive tumors.
Image © Michelle Taras