On the diagnosis of minimal breast cancer in a screenee population.

As a result of screening of 8100 consecutive volunteers, 67 breast cancers have been detected. Fourteen percent of these cancers were found in women aged 35-44 years. Eighty percent of the cancers found in this age group were minimal breast cancer. This percentage decreased significantly in each subsequent decade until age 65 years, or older, when it began to rise once more. While mammography was responsible for detecting the majority of in situ or minimal cancers, 13 were found on physical examination, six of which were found only by physical examination.