Jacky Luiten

58 | Chapter 4 Table 4.7 (continued) High‐risk lesion at biopsy Cancer at biopsy P ‐value Lymph‐node status of invasive cancers (%) N+ N0 Unknown 0 (0) 9 (69.2) 4 (30.8) 447 (21.9) 1543 (75.7) 47 (2.3) <0.001 Grade (%) B&R I B&R II B&R III Unknown 6 (46.2) 3 (23.1) 4 (20.7) 0 (0) 889 (43.6) 889 (43.6) 238 (11.7) 21 (1.0) 0.172 Estrogen receptor (%) Positive Negative Unknown 9 (69.2) 4 (30.8) 0 (0) 1838 (90.2) 189 (9.3) 10 (0.5) 0.065 Progesterone receptor (%) Positive Negative Unknown 6 (38.5) 7 (61.5) 0 (0) 1469 (72.1) 558 (27.4) 10 (0.5) 0.114 Her2/Neu receptor (%) Positive Negative Unknown 3 (23.1) 10 (76.9) 0 (0) 185 (9.1) 1842 (90.4) 10 (0.5) 0.166 Triple receptor – negative (%) 3 (21.4) 129 (6.3) 0.739 Type of final surgical treatment, (%) Breast conserving surgery Mastectomy No surgery performed* Unknown 41 (83.7) 6 (12.2) 2 (4.1) 0 (0) 2067 (81.5) 437 (17.2) 28 (1.1) 5 (0.2) 0.207 DCIS = ductal carcinoma in‐situ; B&R = Bloom & Richardson. * upgraded after follow up with repeated stereotactic biopsy Discussion In a six‐year screening period, we observed a threefold increase in the proportion of high‐risk lesions diagnosed at CNB. The excision rate for these lesions per 1,000 screens and per 100 recalls also tripled. The overall upgrade rates of high‐ risk breast lesions to (in situ) malignancy after excision was 29.0%. Tumor characteristics were distinctively different for cancers diagnosed after upgrading of a high‐risk lesion compared to cancers with an unequivocal malignant outcome at CNB. A Dutch study, performed shortly after the implementation of full‐field digital screening mammography, reported that microcalcifications were more often diagnosed, compared to screen‐film mammography. This resulted in more CNB,