Quality Control of Breast Cancer Screening in Kashiwazaki City Based on Results of Niigata Prefecture

Abstract

Improving the accuracy of breast cancer screening is important in order to reduce disadvantages for subjects. We evaluated the recall rate (RR), the discovery rate (DR) and the positive predictive value (PPV) in Kashiwazaki City based on municipality results that have been publishing by Niigata Prefecture since 2003. Inspection and palpation were abolished in Kashiwazaki City in 2012. The medical association that is responsible for most of the populationbased screening in Kashiwazaki City began conducting comparative interpretations after introducing digital mammography. Comparing the three years before and after 2012, the RR decreased significantly (8.60% vs. 4.47%, p < 0.05). Regarding the screening accuracy of Kashiwazaki City, which is summarized every three years from 2009 to 2020, the RR was lower than that of the prefecture as a whole in all periods, and the PPV was high. The difference in the PPV gradually increased even after 2015. The DR temporarily fell below the prefecture’s overall rate. The difference in the PPV was small until 2014, and increased to more than 5.9% after 2015. In Kashiwazaki City, a good accuracy was achieved in the prefecture by cooperating with local examination facilities and sharing the results at the screening committee. The quality control results in Niigata Prefecture were useful materials for sharing information.