A physical examination was used to screen for breast cancer in 2,500 women with biopsy-proven adenocarcinoma of the breast and in 5,000 age- and race-matched control women. The results of the physical examination were positive (i. e., a mass was palpated) in 1,800 cases and in 800 control women, all of whom showed no evidence of cancer at biopsy. 1. The sensitivity of the physical examination was: 2. The speciicity of the physical examination was: 3. The positive predictive value of the physical examination was: