Screening for breast cancer.

To be successful, screening procedures must have certain properties: simplicity, acceptability, reasonable costs, and adequate sensitivity. The evolution of mammography over the past 10 years has allowed the examination to fall within accepted standards for these properties, and it has become a widely accepted procedure. Its expanded use has resulted in an increase in the detection of early stage disease with a profound effect upon the treatment of the disease. Survival continues to correlate with cancer size and nodal involvement, and the increase in the number of early cases diagnosed eventually should be reflected in a decreasing mortality rate. Though the efficacy of screening mammography for women between the ages of 50 and 69 is well-established, its usefulness in women aged 40-49 has provoked considerable debate. Despite the disagreements concerning appropriate screening thresholds and intervals, the American Cancer Society and the American College of Radiology have concluded that sufficient evidence exists to maintain published guidelines.