Mammograms may not save lives after all. A new study in the "British Medical Journal" reports death rates in women who were screened for breast cancer are the same as rates among women who were not. In cases where mammography detected cancer, one in five cases did not pose a threat to the patient's health and did not require chemotherapy, surgery or radiation. Researchers did not find any advantage to finding breast cancers when they were still too small to feel. The study may widen the rift between advocates who believe regular mammograms save lives and researchers who say the evidence is murky.