(A) Mammograms are less effective than breast self-examination for the diagnosis of abnormalities in younger women, who have denser breast tissue. They are more effective forwomen older than 40. (B) Up to 15% of early-stage breast cancers are detected by physical examination; however, 95% are detected by women doing breast self-examination. (C) Ultrasound is used primarily to determine the location of cysts and to distinguish cysts from solid masses. (D) Monthly breast self-examination has been shown to be the most effective method for early detection of breast cancer. Approximately 95% of lumps are detected by women themselves.