DCIS histopathology from a historical perspective.

Ductal carcinoma in situ (DCIS) represents a biologically and morphologically heterogeneous disease. It is characterized by a proliferation of presumably epithelial malignant cells confined within the lumens of the mammary ducts, without evidence of invasion beyond the basement membrane into the adjacent breast stroma. With the widespread use of screening mammography, a dramatic change has occurred in the frequency, management and types of DCIS detected. Historically, there has been some confusion regarding the definition of DCIS and the terminology associated with the histological types of DCIS. In this review, DCIS histopathology from a historical point of view is presented.