From the Guidelines
Breast calcifications form through various pathophysiological processes that involve calcium deposition in breast tissue, often resulting from cell secretions, cellular debris, or inflammation, and can be benign or malignant in nature. These calcifications develop when calcium salts precipitate in the breast due to degenerating epithelial cells in terminal ductal lobular units, fibroadenomas, inflammatory processes like fat necrosis, or ductal carcinoma in situ (DCIS) and some invasive cancers 1. The morphology, distribution, and pattern of these calcifications on imaging help differentiate between benign processes and potentially malignant conditions, with irregular, clustered, and pleomorphic calcifications raising more concern for malignancy than the smooth, round calcifications typically associated with benign conditions.
Some key points to consider in the pathophysiology of breast calcifications include:
- Benign conditions, such as normal aging, fibroadenomas, and inflammatory processes like fat necrosis, can lead to calcification formation 1
- Malignant conditions, such as DCIS and some invasive cancers, can also lead to calcification formation, often appearing as fine, pleomorphic, or linear branching patterns on mammography 1
- The size and extent of DCIS, as well as the presence of malignant calcifications, are important factors in determining the appropriate treatment approach, including breast-conserving surgery and radiation therapy 1
- Certain factors, such as a history of collagen vascular disease, prior therapeutic radiation, and pregnancy, may preclude the use of radiation in the treatment of patients with DCIS 1
In terms of diagnosis and management, the BI-RADS assessment categories can be used to classify mammographic findings, including breast calcifications, with categories ranging from negative (category 1) to highly suggestive of malignancy (category 5) 1. The most recent and highest quality study, published in 2009, provides guidance on the diagnosis and management of breast cancer, including the use of BI-RADS assessment categories and the importance of considering the morphology, distribution, and pattern of calcifications on imaging 1.
From the Research
Pathophysiology of Breast Calcifications
The pathophysiology of breast calcifications is a complex process that involves the formation of calcium deposits in the breast tissue.
- Breast calcifications can be associated with both benign and malignant conditions, including ductal carcinoma in situ (DCIS) and fibrocystic changes 2, 3, 4, 5.
- DCIS is a non-invasive malignancy that is commonly detected on screening mammograms as calcifications, and its progression to invasive ductal carcinoma (IDC) is not fully understood 6.
- The growth dynamics of mammographic calcifications can help differentiate DCIS from benign breast disease, with DCIS calcifications growing faster and being more extensive at diagnosis 2.
Imaging Features of Breast Calcifications
- Magnetic resonance imaging (MRI) can be useful in the evaluation of DCIS, with common enhancement patterns including clumped linear-ductal enhancement, clumped focal enhancement, and masslike enhancement 3.
- Dedicated breast computed tomography (CT) can also help differentiate DCIS from benign micro-calcifications, with DCIS being more conspicuous on contrast-enhanced CT 4.
- MRI descriptors such as lesion morphology, enhancement patterns, and kinetic curves can help differentiate DCIS from fibrocystic changes, with pathognomonic imaging features present in a subset of cases 5.
Molecular Etiology of DCIS
- The molecular etiology of DCIS is complex and involves the interplay of multiple genetic and epigenetic factors, with each DCIS lesion being heterogeneous in morphology, genetics, and clinical behavior 6.
- Understanding the molecular mechanisms underlying DCIS progression to IDC is crucial for the development of targeted therapies, and new strategies are needed to overcome the current gaps in knowledge 6.