Screening for Breast Cancer
Cancer screening is testing done on people who may be at risk of getting cancer, but who have no symptoms and generally feel fine. Screening can find breast cancers when they are small, less likely to have spread and more likely to be treated successfully. Women ages 50 to 74 have a lower risk of dying from breast cancer when they are screened regularly with mammograms.
Mammography (also called mastography) 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 or microcalcifications.
Like all X-rays, mammograms use doses of ionizing radiation to create images. These images are then analyzed for any abnormal findings. It is normal to use 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. 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 not seen on mammograms. Ductograms are still used in some institutions for evaluation of bloody nipple discharge when the mammogram is non-diagnostic. MRI can be useful for further evaluation of questionable findings as well as for screening pre-surgical evaluation in patients with known breast cancer to detect any additional lesions that might change the surgical approach, for instance from breast-conserving lumpectomy to mastectomy. Other procedures being investigated include tomosynthesis. https://en.wikipedia.org/wiki/Mammography