The week after Leah Severson was diagnosed with breast cancer at age 42, a federal task force came out with new recommendations suggesting women need not undergo regular mammograms until they turn 50. The advice shocked the Westfield mother, who had no indication she might have the disease that affects as many as one in eight women.She didn't smoke, had no family history of breast cancer, was healthy and felt no lumps when she did self-exams. She also underwent regular mammograms.