Microcalcifications
Microcalcifications are tiny deposits of calcium phosphate or calcium oxalate found in soft tissues, notably in the breast. They appear as fine white flecks on a mammogram, typically measuring less than one millimeter in diameter. While microcalcifications are common and often benign, they can sometimes signal precancerous changes, particularly ductal cancer in situ (DCIS). Risk factors associated with their occurrence include age, fat necrosis, breast cysts, and a history of infections or trauma. Detection primarily occurs through routine mammograms, which allow radiologists to assess the characteristics of these calcifications and categorize them based on potential risk. Categories range from benign findings that require no follow-up to those that may indicate malignancy, necessitating further diagnostic procedures. Importantly, the vast majority of microcalcifications are not cancerous, yet their presence may increase the risk of developing breast cancer in the future. Understanding microcalcifications is crucial for early detection and management of potential breast health issues.
On this Page
Microcalcifications
ALSO KNOWN AS: Calcifications, mammary microcalcifications (MCs),
RELATED CONDITIONS: Ductal cancer in situ (DCIS), ductal carcinoma in situ (DCIS), invasive ductal carcinoma (IDC)
DEFINITION: Microcalcifications are tiny deposits of calcium phosphate or calcium oxalate found in soft tissues of the body, such as the breast. On a mammogram, microcalcifications are seen as fine white flecks with a diameter of less than one millimeter. Based on their physical characteristics and location, microcalcifications may be classified as skin, vascular, eggshell, popcorn-like, rod-like, punctate (round or oval), milk of calcium, or suture. Although they are very common and usually benign, microcalcifications may indicate precancerous changes in the breast.
Risk factors: The incidence of microcalcifications increases with age. Fat necrosis, breast cysts or lumps, and a history of breast infections increase the chances of calcifications. They occur in women and men of all ages and races.
Etiology and the disease process: Microcalcifications are not associated with dietary calcium. They are thought to be secreted by the breast cells or mineralized residues from either normal breast metabolism or abnormal, rapid cell division. They may be related to previous trauma, surgery, infection, or radiation, or they may be an indication of ductal cancer in situ, a noninvasive Stage 0 cancer found in the milk ducts of the breast.
Incidence: Microcalcifications and larger macrocalcifications are seen in approximately two-thirds of all mammograms.
Symptoms: The deposits are generally too small to be felt during clinical examinations and do not cause pain.
Screening and diagnosis: Screening mammograms are the standard tool for detecting microcalcifications. Radiologists use diagnostic mammography, computer-assisted detection software, ultrasound, and comparisons with previous mammograms to analyze the structure, size, number, shape, and distribution of microcalcifications. The findings are then assigned an assessment category (from 0 to 5) to determine recommended follow-up.
Treatment and therapy: Mammograms classified as categories 1 and 2 are considered negative and require no extraordinary follow-up. Category 3 microcalcifications are highly likely benign, but repeat mammograms are typically scheduled to watch for changes in the size, number, or shape of deposits. A stereotactic or surgical biopsy of suspicious microcalcifications may be recommended with a category 4 assessment. In contrast, a category 5 designation indicates a likely malignancy requiring biopsy, surgery, or other treatment. Category 0 is used when additional testing is needed before making a diagnosis.
Prognosis, prevention, and outcomes: Around 98 percent of microcalcifications are benign. Of those biopsied, more than 80 percent are noncancerous. However, any microcalcifications (especially if they occur in both breasts) are thought to put women at greater risk for breast cancer. Needle localization helps detect early-stage breast cancer in difficult-to-detect microcalcifications.
Bibliography
"American Cancer Society Recommendations for the Early Detection of Breast Cancer." American Cancer Society, 19 Dec. 2023, www.cancer.org/cancer/types/breast-cancer/screening-tests-and-early-detection/american-cancer-society-recommendations-for-the-early-detection-of-breast-cancer.html. Accessed 20 June 2024.
"Breast Calcifications." MedlinePlus, 27 Apr. 2024, my.clevelandclinic.org/health/diseases/17802-breast-calcifications. Accessed 20 June 2024.
Chotai, Niketa, and Supriya Kulkarni. Breast Imaging Essentials: Case Based Review. Springer, 2020.
Joe, Bonnie N., and Amie Y. Lee. Breast Imaging. 4th ed., Elsevier, 2023.
Logullo, Angela F., et al. “Breast Microcalcifications: Past, Present and Future (Review).” Molecular and Clinical Oncology, vol. 16, no. 4, 2022. p. 81. doi:10.3892/mco.2022.2514.
Love, Susan, et al. Dr. Susan Love's Breast Book. 7th ed., Da Capo, 2023.
"Mammograms." National Cancer Institute, 21 Feb. 2023, www.cancer.gov/types/breast/mammograms-fact-sheet. Accessed 20 June 2024.
Tan, Puay H., and Aysegul A. Sahin. Atlas of Differential Diagnosis in Breast Pathology. Springer, 2017.
Wechter, Debra G. "Mammogram—Calcifications." MedlinePlus, 3 Nov. 2023, medlineplus.gov/ency/article/002113.htm. Accessed 20 June 2024.
"What Does the Doctor Look For on a Mammogram?" American Cancer Society, 14 Jan. 2022, www.cancer.org/cancer/types/breast-cancer/screening-tests-and-early-detection/mammograms/what-does-the-doctor-look-for-on-a-mammogram.html. Accessed 20 June 2024.