Number of skin moles tied to breast cancer risk
Women’s disease increase may reflect higher estrogen levels
By Nathan Seppa
Women who have many moles on their skin are slightly more prone to breast cancer than those without them, two studies find. Skin moles, benign clumps of pigmentation-producing cells called melanocytes, might arise from high levels of hormones in women’s blood, which also could facilitate tumor growth, one of the studies suggests.
Although the appearance of moles can be influenced by an individual’s genetics, the new studies and earlier work suggest that exposure to estrogen plays a role, too, says Barbara Fuhrman, an epidemiologist at the University of Arkansas for Medical Sciences in Little Rock. Like cells in the breast and elsewhere, melanocytes have receptor proteins that estrogen can bind to, triggering cell activities that include growth.