The actual occurrence of cancer of the breast as recorded in the surgical pathologic laboratory of the Johns Hopkins University and Hospital has decreased from 80 per cent in 1900 to 17 per cent in 1929. A few years ago it was 20 per cent. When every woman over 25 years of age reports within a month after her first warning by any sign or symptom in one or both breasts, the actual percentage of cancer will be lower than 17. It is only right to record next that this tremendous reduction in the percentage of cancers between 1900 and 1929 is due to the recognition of a large group of breast lesions which have the signs and symptoms of the earliest stages of cancer but which are not cancer. The majority of these lesions do not develop into cancer but disappear and get well of themselves. This is a