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History and status of x-ray mammography.

Mammography is a relatively recent addition to the array of x-ray services available for the detection, diagnosis, and staging of cancer. Technological advances over the past two decades have led to substantial improvements in the quality of mammographic images and reductions in patient doses of more than an order of magnitude. Today x-ray mammography is used not only to characterize suspicious regions of breast tissue discovered by physical examination, but also to screen asymptomatic women for the early detection of breast cancer. National programs have been established to help ensure high quality images, accurate interpretations, and efficient utilization of x-radiation in the detection and diagnosis of breast cancer. In all of the advances that have lead to widespread utilization of mammography, physicists have played a substantial role.