ABSTRACT
This chapter introduces the biological effects of ionizing radiation, as well as the concepts of excess risk and the benefits of breast cancer screening. It presents several groups have attempted to establish an estimate of radiation risk in a modern screening program, and a comparison of their approaches. The chapter describes the trends in radiation dose levels in screening mammography and breast tomosynthesis. For radiation measurement, the “absorbed dose” is measured in grays, which is a unit of energy deposited per unit of irradiated mass. There are a number of studies that have attempted to estimate the risk of radiation-induced cancer related to modern screening mammography exams. Screening mammography has been shown to reduce mortality and morbidity by earlier detection of breast cancer. Digital breast tomosynthesis has been proposed as an alternative to digital mammography that reduces the impact of tissue superposition by imaging the breast at different angles and reconstructing a series of planes through the breast.
