When a woman undergoes a mammogram, the radiologist analyzes the breast tissue to check for signs of breast cancer. We've compiled a list of eight important facts to know about mammograms based on information from breastcancer.org. 1. Regular mammograms can detect breast cancer early: Catching breast cancer when it's at an early stage can reduce the risk of dying from the disease by up to a third. Mammograms are the most reliable method of detecting breast cancer and will catch 80 percent of cases. Experienced radiologists can detect breast cancer on mammograms in split seconds.