Strategy in the Management of in situ Carcinomas of the Breast: Clinical, Diagnostic, and Surgical Aspects

The frequency and histologic pattern of in situ lesions of the breast are changing. In earlier surgical materials, the frequency of in situ carcinomas was only 2%–3% in relation to invasive breast cancer, and lobular carcinoma in situ (LCIS) predominated over ductal carcinoma in situ (DCIS) by a ratio of 2:1 or more (Farrow 1970). In recent mammographic screening materials, on the other hand, DCIS is 3–5 times more common than LCIS, and the incidence in relation to invasive breast cancer is rising to 10%–25% (Andersson 1981; Gad et al. 1984). Clearly, an increased intensity of diagnostic activity, such as mammographic screening programs, leads to an increase in the detection of carcinoma in situ lesions. The changing LCIS/DCIS ratio can be explained by the fact that mammography demonstrates microcalcifications, characteristic of DCIS rather than LCIS.