Twenty-year follow-up of minimal breast cancer from the Breast Cancer Detection Demonstration Project.

Since the 1960s, the potential benefits of early detection of breast cancer through screening with physical examination and mammography have been studied. In a mass screening study begun in 1973 by the Breast Cancer Detection Demonstration Project (BCDDP), mammography detected 90% of the cancers that were diagnosed. Of the women aged 35 to 74 years from the BCDDP study who were diagnosed with minimal breast cancer, the 20-year cumulative breast cancer survival rates were 95.8% for 469 women with in situ breast cancer and 82.8% for 769 women with invasive breast cancers 1 cm or smaller in size.