Two-view mammography at the incident round has improved the rate of screen-detected breast cancer in Wales

To investigate whether pre-invasive and invasive cancer detection rates were improved in Wales after the introduction of two views at incident screens. The records of women attending follow-up screening for 2 years before and 2 years after the introduction of two-view incident screening were analysed. Cancer detection rates were compared before and after introduction of two view screening. At the incident round 98,752 women had one and 95,464 had two views. Five hundred and fifty-five cancers were detected with one view and 744 with two, an increased detection rate from 5.6 to 7.8 cancers per 1000 women screened ( p=0.01). Two hundred and thirty-nine small cancers were detected with one view and 323 with two, increasing the detection rate from 2.4 to 3.4 per 1000 women screened ( p=0.05). Two-view mammography at incident rounds detects more cancers and more favourable prognosis small cancers than single-view mammograms.