Comedonecrosis

Comedonecrosis is a term pathologists use to describe a specific type of cell death (necrosis) found in certain cancers. It occurs when cancer cells in the center of a tumour grow rapidly but outgrow their blood supply. Without enough blood, oxygen, and nutrients, these cells die, forming an area of dead cells and debris. This dead material often appears as a thick, pasty substance when viewed under a microscope, resembling the material seen in a blocked skin pore (called a comedo), hence the name “comedonecrosis.”

What types of cancer show comedonecrosis?

Comedonecrosis is most commonly found in breast cancers, particularly in ductal carcinoma in situ (DCIS), a non-invasive breast cancer. Certain types of invasive breast cancers can also show comedonecrosis. Although it’s most common in breast cancers, similar patterns of necrosis can occasionally be seen in cancers from other parts of the body.

What is the significance of finding comedonecrosis in cancer?

The presence of comedonecrosis in a pathology report is significant because it often indicates an aggressive form of cancer. In ductal carcinoma in situ (DCIS) of the breast, for example, the presence of comedonecrosis is associated with a higher grade, meaning the cancer cells grow faster and look more abnormal. Identifying comedonecrosis helps your doctors determine the best course of treatment and follow-up care.

What does comedonecrosis look like under the microscope?

Under the microscope, comedonecrosis looks like a solid area of necrosis (dead cells) and debris in the center of cancerous glands or ducts. It often appears as a pale, pinkish-white or grayish, granular (grainy), and pasty material. Living cancer cells typically surround these central areas of necrosis. This distinctive appearance helps pathologists identify comedonecrosis and distinguish it from other types of cell death.