Millions of women who take combination hormones to counter symptoms of menopause may be three times more likely to develop a certain type of breast cancer, according to a new study. Most researchers assumed it takes five years of daily estrogen and progestin to increase cancer risks, but the threat may increase substantially in just three years, according to research published in Cancer Epidemiology, Biomarkers and Prevention.
The risk only increased for lobular breast cancer, which accounts for 15% of breast cancer cases each year. Many doctors still offer the controversial therapy to treat menopausal symptoms like hot flashes, despite its link to cancer. "Nothing is risk-free. A lot of women need combination hormones because they're miserable," said one gynecologist. "If it's three years instead of five, we'll deal with that."