[Mass screening for breast cancer in Miyagi prefecture--a 5-year review].

During the past 5 years, 55839 individuals mass screening for breast cancer in Miyagi Prefecture. Breast cancer was detected in 51 of 49114 (0.1%) women examined at the local site and in 14 of 6725 (0.2%) women examined at the vocational site. At the Cancer Detection Center (CDC) breast cancer was detected in 75 of 3055 (2.4%) screened individuals. Of the 51 breast cancer patients identified at the local site, 35 had noted a breast lump before screening, 6 of 14 patients identified at the vocational site had noted a lump. All patients in whom cancer was detected at the CDC had noticed a breast lump before undergoing the examination. Tumors were detected at a relatively early stage at the vocational site. Classification of tumor size was not significantly different between the local and the CDC examination.