Is DCIS “cancer” or not?

One of the reasons there is so much debate about what to call DCIS is that the words “cancer” and “carcinoma” provoke such strong emotional reactions. Many people’s first response is to want to remove or destroy it as quickly as possible. However, many years of research have shown that cancerous cells are not a single entity or type; some do not grow rapidly, or even at all.

These cells, when examined under a microscope, can show behaviors in the body that range from rapidly invasive at one end of the spectrum to very slow or even non-growing at the other, staying contained. While doctors agree that cells which show invasion under the microscope need to be removed by surgery or destroyed by radiation or other therapies, there is much more debate and disagreement about what to do with cells that are contained, such as DCIS in the milk ducts of the breast.