Ductal Carcinoma in Situ (Intraductal Carcinoma) of the Breast

IN 1932, Broders defined carcinoma in situ as "a condition in which malignant epithelial cells and their progeny are found in or near positions occupied by their ancestors before the ancestors underwent malignant transformation."1 In the breast, carcinoma in situ has been categorized traditionally as either lobular or ductal, depending on the cytologic features and pattern of growth. Ductal carcinoma in situ, more commonly known as intraductal carcinoma, is characterized by a proliferation of malignant epithelial cells confined to the mammary ducts, without light-microscopical evidence of invasion through the basement membrane into the surrounding stroma. Unfortunately, in the past some . . .