Most women who find their own breast
cancer do so as part of normal routines (showering,
getting dressed, etc.) and not during systematic
monthly breast self-exams.
About 80% of breast cancers not discovered by mammography are discovered by women themselves, but this is most often as part of daily living, showering, getting dressed, etc., not as part of a systematic, regular breast self-examination.
The results of prospective randomized clinical trials have demonstrated that routine breast self-examinations (BSE) do not lead to a decrease in mortality from breast cancer nor do they find cancer at earlier stages. The United States Preventive Services Task Force (USPSTF) no longer recommends health care providers teach the procedure to women. The National Cancer Institute states that “based on solid evidence, formal instruction and encouragement to perform breast self-examination leads to more breast biopsies and to the diagnosis of more benign breast lesions” and based on evidence “does not reduce breast cancer mortality.”
For more information, read NBCC’s position statement on BSE.