Mammographically detected carcinoma of the breast.

A ten year experience with 2,077 consecutive mammographically guided needle-localization biopsies at a large community hospital is presented. By using this technique, 13.8 per cent of the biopsies were positive, yielding 284 carcinomas. The nonpalpable carcinomas discovered by mammography and the needle-localization technique were compared with those palpable carcinomas diagnosed during the same time period at York Hospital. In the final year of the study, 42.1 per cent of carcinomas treated at the York Hospital were diagnosed by the needle-localization technique. The mammographically detected carcinomas were smaller, more often node-negative and found, on average, at an earlier patient age than palpable carcinomas. The results of this study demonstrate that screening mammography, coupled with an aggressive biopsy policy, will lead to the discovery of many early, node-negative carcinomas of the breast.