Mammography (also called mastography; DICOM modality: MG) is the process of using low-energy X-rays (usually around 30 kVp) to examine the human breast for diagnosis and screening. The goal of mammography is the early detection of breast cancer, typically through detection of characteristic masses, microcalcifications, asymmetries, and distortions. As with all X-rays, mammograms use doses of ionizing radiation to create images. These images are then analyzed for abnormal findings. It is usual to employ lower-energy X-rays, typically Mo (K-shell X-ray energies of 17.5 and 19.6 keV) and Rh (20.2 and 22.7 keV) than those used for radiography of bones. Mammography may be 2D or 3D (tomosynthesis), depending on the available equipment or purpose of the examination. Ultrasound, ductography, positron emission mammography (PEM), and magnetic resonance imaging (MRI) are adjuncts to mammography. Ultrasound is typically used for further evaluation of masses found on mammography or palpable masses that may or may not be seen on mammograms. Ductograms are still used in some institutions for evaluation of bloody nipple discharge when a mammogram is non-diagnostic. MRI can be useful for the screening of high-risk patients, for further evaluation of questionable findings or symptoms, as well as for pre-surgical evaluation of patients with known breast cancer, in order to detect additional lesions that might change the surgical approach (for example, from breast-conserving lumpectomy to mastectomy). In 2023, the U.S. Preventive Services Task Force issued a final recommendation statement that all women should receive a screening mammography every two years from age 40 to 74. The American College of Radiology, Society of Breast Imaging, and American Cancer Society recommend yearly screening mammography starting at age 40. The Canadian Task Force on Preventive Health Care (2012) and the European Cancer Observatory (2011) recommend mammography every 2 to 3 years between ages 50 and 69. These task force reports point out that in addition to unnecessary surgery and anxiety, the risks of more frequent mammograms include a small but significant increase in breast cancer induced by radiation. Additionally, mammograms should not be performed with increased frequency in patients undergoing breast surgery, including breast enlargement, mastopexy, and breast reduction.
Types
Digital Digital mammography is a specialized form of mammography that uses digital receptors and computers instead of X-ray film to help examine breast tissue for breast cancer. The electrical signals can be read on computer screens, permitting more manipulation of images to allow radiologists to view the results more clearly. The standard digital mammography is "full field" (FFDM), in which the entire breast is imaged in a single view. Digital mammography can also include the use of "spot views", in which a paddle is used to further compress areas of concern. Digital mammography is also utilized in stereotactic biopsy. Breast biopsy may also be performed using a different modality, such as ultrasound or magnetic resonance imaging (MRI). While radiologists had hoped for more marked improvement, the effectiveness of digital mammography was found comparable to traditional X-ray methods in 2004, though there may be reduced radiation with the technique and it may lead to fewer retests. Specifically, it performs no better than film for post-menopausal women, who represent more than three-quarters of women with breast cancer. The U.S. Preventive Services Task Force concluded that there was insufficient evidence to recommend for or against digital mammography over basic film mammography for breast cancer screening. Digital mammography is a NASA spin-off, utilizing technology developed for the Hubble Space Telescope. As of 2022, over 99% of certified mammography centers in the United States screening centers use digital mammography. Globally, systems by Fujifilm Corporation are the most widely used. In the United States, GE's digital imaging units typically cost US$300,000 to $500,000, far more than film-based imaging systems. Costs may decline as GE begins to compete with the less expensive Fuji systems.
3D mammography Three-dimensional mammography, also known as digital breast tomosynthesis (DBT), tomosynthesis, and 3D breast imaging, is a mammogram technology that creates a 3D view of the breast using X-rays from different angles. Supplementing standard 2D mammography with DBT has been shown to improve cancer detection. Cost effectiveness is unclear as of 2016. Another concern is that it more than doubles the radiation exposure.
Contrast-enhanced mammography Contrast-enhanced mammography is an advanced imaging technique that employs iodinated contrast agents to visualize breast neovascularization, functioning similarly to magnetic resonance imaging. Tumor-associated angiogenesis often results in leaky blood vessels, allowing contrast material to accumulate within the tumor tissue and produce an iodine-enhanced image. This enhances the visibility of malignancies that might otherwise be obscured by dense breast tissue. Contrast-enhanced mammography is also referred to as contrast-enhanced spectral mammography, contrast-enhanced digital mammography, or contrast-enhanced dual-energy mammography. A large randomized controlled trial published in The Lancet in 2025 found that contrast-enhanced mammography detects significantly more invasive breast cancers in women with dense breast tissue than standard mammography or ultrasound. Conducted across 10 U.K. screening sites with over 9,000 participants, the study reported that contrast-enhanced mammography identified 15.7 invasive cancers per 1,000 exams, compared to 4.2 for ultrasound and 15 for MRI, with no statistically significant difference between Contrast-enhanced mammography and MRI. CEM was also found to be more cost-effective and accessible than MRI. Advocates suggest contrast-enhanced mammography could improve early detection and outcomes for women with dense breasts, but acknowledge risks of overdiagnosis.
Photon counting
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