When MIT artificial intelligence expert Regina Barzilay returned to work after breast cancer leave seven years ago, she wondered if their sophisticated algorithmic work could be used to predict cancer. Now Barzilay, 51, and a student protege have built an AI that seems able to predict with amazing accuracy whether a healthy person will get breast cancer. By analyzing a mammogram's pixels and cross-referencing them with thousands of older mammograms, the open-source AI — known as Mirai — can predict nearly half of all incidences of breast cancer up to five years before they happen. Assuming that validation happens — trials are about to begin — Mirai could give patients a chance to make health-care choices that earlier generations could only dream of. "This is the next, very positive step forward," said Dorraya El-Ashry, chief scientific officer for the Breast Cancer Research Foundation, which provided funding for Barzilay's research, as did MIT's Jameel Clinic and the British nonprofit Wellcome Trust.