Jacky Luiten

Trends in frequency and outcome of high‐risk breast lesions at CNB |49 4 Introduction Many countries have implemented regional or nationwide screening mammography programs with the aim to detect breast malignancy at an early stage to decrease breast cancer related morbidity and mortality. 1,2 Recalled women frequently have to undergo some kind of image‐guided core needle biopsy in order to obtain a definite diagnosis for the abnormality detected at screening mammography. Women with benign biopsy results are usually encouraged to reattend the screening program and those diagnosed with malignant breast disease generally have an excellent prognosis after appropriate treatment. However, optimal management of so‐called high‐risk lesions, also known as risk‐associated lesions (e.g.; flat epithelial atypia, papillary lesions, radial scar and lobular carcinoma in situ [LCIS]), found at core needle biopsy (CNB) is controversial. 3‐6 Communication between radiologists, pathologists and surgical oncologists is crucial to determine whether a high‐risk lesion should either be monitored by regular radiologic follow‐up imaging or whether excision can be considered. Stereotactic core needle biopsy (SCNB) is performed more often since the introduction of digital mammography in breast cancer screening, probably because digital mammography has a higher sensitivity for the detection of small calcifications compared to screen‐film mammography. 7 It is not clear, however, to which degree high‐risk lesions are more frequently diagnosed in screened women. It also remains indistinct whether these lesions have a significant impact on the diagnostic surgical excision rate to obtain a final tissue diagnosis. Therefore, we determined trends in frequency, management and pathology outcome of high‐risk breast lesions found at CNB in women who were recalled at a biennial screening mammography program in the south of the Netherlands. We determined the rate of “upgrade” to ductal carcinoma in situ (DCIS) or invasive carcinoma to support an evidence‐based approach to the management of high‐risk lesions. “Upgrade” was defined as a change of diagnosis into DCIS or invasive carcinoma at final pathology after diagnostic surgical excision for lesions, which originally were classified as high‐risk lesions at CNB or SCNB. Materials and methods Study population and screening procedure We included all screening mammography examinations obtained in a southern breast cancer screening region of the Netherlands between January 1, 2011, and