Single oblique-view mammography for periodic screening for breast cancer in women.

A population, originally 6,845 women, 40 years of age and over, was screened for breast cancer by single oblique-view mammography in 1974, 1977, and 1980. Of the 5,789 women remaining in their parish in 1980, 94% had attended the screening at least once. Of 111 breast cancers diagnosed in the 6.25-year study period, 78% were detected at screening, 15% as interval cancers, and 7% among nonresponders. Sixty-three percent of the women had tumors in clinical stage I, and 59% had tumors less than or equal to 10 mm. The predictive value for biopsy recommendations by mammography was 79%. This method was considered very suitable for screening. In the older age groups there was probably some overdiagnosis of cancers that would never have become symptomatic.