Jacky Luiten

80 | Chapter 5 which rose threefold in comparison with the lesser increase of both intermediate‐ and high grade DCIS. Almost all patients with microcalcification‐associated DCIS are treated with surgery, the majority consisting of breast‐conserving treatment. SCNB has replaced surgical excision biopsies and is currently the preferred technique for the diagnosis of microcalcification‐associated breast abnormality. 20‐24 However, given the observed decrease in PPV for microcalcification recalls, one might question whether all recalled microcalcifications necessitate biopsy. Unfortunately, any underlying malignancy cannot always be ruled out with additional breast imaging, making SCNB the preferred minimally invasive technique to obtain tissue for pathologic examination. Several studies showed that FFDM may be more effective than SFM for the detection of microcalcifications, as was also demonstrated in this study. Another explanation for the increased recall rate of microcalcifications may be the performance of routine two‐view mammography (mediolateral oblique and craniocaudal views) of each breast since the start of FFDM in 2009‐2010. In the SFM period, all women attending the program for the first time underwent two‐ view mammography, whereas subsequent screening examinations consisted of a routine mediolateral oblique view of each breast and additional craniocaudal views only if indicated 3,25,26 . Depending on the characteristics of mammography screening programs, adding tomosynthesis to conventional FFDM may have a beneficial impact on recall rate and cancer detection. 27 However, breast tomosynthesis has not yet been implemented in the Dutch screening program. The increased detection of DCIS also resulted in a rise in the number of low grade DCIS and thus probably some degree of overdiagnosis, which may pose therapeutic dilemmas for clinicians and may lead to overtreatment. As ongoing studies investigate the possibility of close surveillance of low grade and even intermediate grade DCIS 28,29 , better discrimination of microcalcifications to prevent SCNB for suspected low grade DCIS based on radiologic features might be a next step in deescalating treatment. High grade DCIS is more often associated with specific abnormal mammographic features, such as necrosis, rod and linear branch shapes, or coarse granular microcalcifications. 5,30‐32 On the other hand, more than half of DCIS related to suspicious microcalcifications in our study showed high grade histopathologic characteristics. As the detection and subsequent treatment of high grade DCIS may reduce further development to high grade invasive carcinoma, histologic analysis of screen‐detected microcalcifications carries substantial clinical value. 9 Consequently, SCNB is still considered mandatory in the work‐up of these lesions to date because it is not yet