Breast Calcifications: The Focal Group

Abstract

B reast calcifications are common findings on mammography and may reflect both benign and malignant causes (Fig. 1). The detection of breast calcifications often necessitates further imaging evaluation. Magnification mammography is the primary technique used for further analysis of calcifications in the breast. Typically, magnified mammographic views in the craniocaudal and mediolateral projections are obtained because this permits differentiation of benign milk of calcium, a form of fibrocystic change, from other worrisome deposits. Magnification mammography decreases noise and increases image sharpness, permitting clearer analysis of the morphology and the distribution of the calcifications. Evaluation of breast calcification morphology and distribution as well as assessing for any interval changes can aid in determining patient management. The morphology and size of calcifications are the most important factors in deciding whether calcifications are typically benign, indeterminate and warranting follow-up imaging or biopsy, or suspicious and requiring biopsy. Macrocalcifications are defined as larger (typically > 2 mm) calcium deposits in the breast tissue that are generally associated with a benign process, such as those related to fat necrosis, involuting fibroadenomas, radiation therapy, or plasma cell mastitis. Microcalcifications are calcific particles smaller than 0.5 mm that can be associated with a malignant process, such as ductal carcinoma in situ or invasive carcinoma. Analysis of the morphology of breast calcifications is helpful in determining the likelihood that the calcifications are benign, probably benign, or malignant (Fig. 2). The distribution of breast calcifications is also useful in differentiating benign from indeterminate and malignant causes (Fig. 3). Diffuse or scattered calcifications, most often bilateral, are distributed randomly throughout the breasts and are typically benign, such as skin calcifications and calcifications associated with fibrocystic change. Regional calcifications are scattered in a larger volume (> 2 cm3) of breast tissue; often involve most of the breast or more than a single quadrant but not in an expected ductal distribution; and favor a benign cause, such as seen with sclerosing adenosis or fibrocystic change. Grouped (or clustered) calcifications, which are defined as at least five calcifications within 1 cm3 of tissue, are most often of intermediate concern for malignancy of the breast. Linear calcifications, which suggest deposits in a duct, are suspicious for malignancy. Segmental calcifications, which are deposited in one or more ducts and branches of a segment or lobe, are typically suspicious for multifocal breast cancer. Most breast calcifications form either within the terminal ducts (intraductal) or within the acini (lobular), both of which Demetri-Lewis et al. Breast Calcifications