Introduction to Ductal Carcinoma in Situ

Classification of Ductal Carcinoma in Situ

The traditional criteria used to classify ductal carcinoma in situ (DCIS) are based on the appearance of the cells under the microscope. The two types of DCIS are classified as follows:

• Comedo DCIS - this type is characterized by the presence of dead (necrotic) cells at the center of the breast ducts which is referred to as comedonecrosis. The comedo type of DCIS is usually more aggressive than the non-comedo types.

• Non-comedo types of DCIS include:

  • Micropapillary DCIS
  • Cribiform DCIS
  • Solid DCIS
  • Papillary DCIS

Based on the extent of how abnormal the cells appear under a microscope, DCIS can be classified as either:

• Low-grade DCIS
• Intermediate-grade DCIS
• High-grade DCIS

Although this grading system is not perfectly accurate, it does provide doctors with some prognostic information as to the likelihood that the cells may develop into invasive cancer or whether the DCIS may recur following surgery. High-grade DCIS carries the highest risk for developing into invasive cancer.