Mammograms don’t prevent breast cancer, but they can save lives by finding breast cancer as early as possible. Finding breast cancers early with mammography has also meant that many more women being treated for breast cancer are able to keep their breasts. When caught early, localized cancers can be removed without resorting to breast removal (mastectomy). Some women wonder about the risks of radiation exposure due to mammography. Modern-day mammography only involves a small amount of radiation — even less than a standard chest X-ray.