The in situ carcinomas of the breast

In situ carcinoma of the breast is being diagnosed with greater frequency on breast biopsies. Of the two types of CIS, lobular carcinoma in situ is considered a marker for increased risk of developing breast cancer in either breast, and treatment options are based on different philosophies of careful follow-up vs preventive surgery. Ductal carcinoma in situ is a direct precursor to invasive carcinoma and the variety of treatments available reflect the need to completely excise this lesion. Several trials are now in progress to define the roles of surgery, radiation, and hormonal manipulation in the treatment of both types of CIS.