Geneticists at the University of Cambridge have found a way to classify breast cancer tumors into 10 subcategories that could help pave the way to targeting therapies to individual patients, the Los Angeles Times reported. The research, published in Wednesday's journal Nature, analyzed the genetic signatures of 997 tumors and how DNA turned genes on and off. The distinct categories that resulted, ranging from very treatable to extremely aggressive, could spare some women the pain of unnecessarily toxic treatments and help scientists pinpoint new treatment options. It is the first of many studies that are expected this year that will use genetic clues to help refine categories of the disease, the Los Angeles Times said.