Jacky Luiten

36 | Chapter 3 performed secondary to a preceding percutaneous biopsy with no classifying diagnosis (secondary excision biopsies). The aim of this study was to analyze the more recent trends in the use and added value of excision biopsies in screen‐detected breast abnormalities and how these trends compare to those observed until 2010. Methods Study population All women who attended the breast cancer screening program at four specialized screening units in the southern part of the Netherlands between January 1997 to January 2017 were asked to give written informed consent to use their screening and follow‐up data for evaluation purpose. Three recalled women refused to give permission. Subsequently, a total of 817,656 screens were included in this study. According to the Dutch Central Committee on Research involving Human Subjects (CCMO) ethical approval was not required for the current study. Screening procedure In the Dutch national screening program screening mammograms are taken biennially by dedicated screening mammography radiographers. Certified screening radiologists double read all mammograms and classify the results according to the Breast Imaging Reporting and Data System (BI‐RADS). 14,15 Women with a BI‐RADS 0, 4 or 5 screening result are recalled to a dedicated breast unit. The Dutch breast cancer screening program has been described in detail in previous studies. 2,16,17 Follow up All women with a suspicious abnormality on screening mammograms (BIRADS 4‐5, classified as; suspicious mass, suspicious calcifications, suspicious mass in combination with calcifications, architectural distortion, asymmetry, or other abnormality) are recalled to specialized breast cancer units for further analysis via their general practitioner. Additional breast radiology examinations will be performed, with or without biopsy. Women are recalled directly to the radiology department in case of an uncertain finding at screening mammography (BIRADS 0). If additional analysis does not reveal a suspicious lesion, women are discharged and the general practitioner is informed.