Results of breast biopsies for mammographic findings.

The results of breast biopsies for mammographic findings have been presented, in which 314 biopsies were done on 274 patients. From this number of biopsies, the diagnosis of cancer was established in fifty-seven cases (18 per cent of the biopsies). More than 50 per cent of the lesions were infiltrating duct cell carcinomas. The number of breast biopsies required increased markedly after the national publicity in 1974. As more biopsies were done, the incidence of carcinoma increased, and a significant number of these were found in women less than fifty years old. We believe this justifies the continued judicious use of mammography, even in the younger patient, if clinically indicated.