In Situ Carcinomas of the Female Breast Incidence, clinical findings and DBCG proposals for management

In situ carcinomas of the female breast (CIS) include lobular carcinoma in situ (LCIS) and ductal carcinoma in situ (DCIS). Also associated are controversial forms of epithelial hyperplasia, lobular cell atypia (ALH) and ductal cell atypia (ADH). Based upon recent Danish autopsy studies, it has been estimated that about 25% of all women will develop in situ carcinoma, predominantly in the form of DCIS. Only a fraction of these lesions will evolve into a clinical manifest form, however. Thus, in a clinical setting, the frequency of CIS is 0.09 cases per 1000 woman-years for a Danish female population aged twenty years or more. The lifetime risk of having CIS demonstrated is estimated at 0.53% for women in this age group. CIS makes up a few per cent of all newly diagnosed breast cancers in Denmark. Enforced employment of mammography in the early detection of breast cancer will increase CIS incidence from about 4-6% to about 9-10% of all newly diagnosed breast cancers, and aggressive DCIS growths will mainly constitute the increment. In concurrence with the new DBCG protocols in 1988, new strategies for the management of in situ carcinomas, based upon histogenetic types and growth patterns, are being introduced. The aim will be breast-conserving treatment whenever it can be achieved.