Crowded dilated ducts exhibit solid/cribriform proliferation of epithelial cells. While ominous looking, there is no invasion here.
Calcifications are common, making this detectable on mammography.
The ductular lumens are packed with eosinophilic necrotic material (comedonecrosis); note the multilayered epithelium.
There is severe nuclear pleomorphism with irregularly piled up cells. This would be a high grade DCIS.
There were areas of microinvasion (bottom) in this case.
Ductal carcinoma in situ, solid and/or cribriform type with necrosis is often referred to as DCIS, comedo-type due to the central necrosis. DCIS is always graded based on cytologic features and the types with central or focal necrosis are often at least intermediate or high grade. The central necrosis often calcifies, creating the coarse calcifications which are picked up on mammogram and provide the catalyst for biopsy, as DCIS rarely makes a mass lesion.
DCIS have various architectural patterns including comedo, cribriform, micropapillary, solid or mixed. Categorizing DCIS by these patterns can be problematic as patterns frequently co-xisit. The solid and cribriform types tend to be higher grade, most with comedo necrosis. Thus, it may be best to grade DCIS using cytologic features (high, intermediate and low grade). The Van Nuys system focuses on cytonuclear grade and the presence of comedo necrosis.
Author: Corinne Stephenson, MD. Dept of Pathology, Vanderbilt University.