CHICAGO (AP) - A study of 37,000 women concludes that taking hormones after menopause did not increase the risk of breast cancer, except for some uncommon forms that are slow-growing and highly treatable.

Those using hormones for five years or less were 1.8 times more likely to have slow-growing, highly curable tumours than women who never took hormones, while those using hormones more than five years were 2.6 times more likely to have the less-threatening tumours.