What is DCIS, or ductal carcinoma in situ?
DCIS means that there are cancer cells in your breast but they have not gone anywhere. They have not invaded beyond the normal breast structures (ducts and lobules) into the surrounding tissues. Once the cells break through ducts and lobules, it is called “invasive”. Once it is invasive, it can spread to your lymph nodes and the rest of your body.
Peggy Orenstein is correct in that DCIS alone will not kill you. Breast cancer solely in your breast will not kill you. Even breast cancer in your bones will not kill you. However, when the cancer cells take over vital organs, such as the liver, lungs, and brain, that is when people eventually die from cancer.
Although some DCIS will never become invasive cancer, DCIS has the potential to become invasive. Although there are some cancers that may never spread to other parts of your body, all invasive cancers have to potential to go to other parts of your body. The problem is it can be hard to predict what the cancer cells in your body are going to do. The blanket statement that DCIS in a 40 year old “quite likely would never become life threatening” (I have seen cases that have proven otherwise) is just not true. It is not that simple and not everyone can be fit into a one size fits all category. So, what is the likelihood that DCIS will become invasive cancer? There are a few things to consider:
1. How aggressive is the DCIS? DCIS is broken down into low, intermediate and high grades, which are determined by characteristics indicative of cell growth. High grade or comedo type DCIS means that the cells are rapidly growing and it is very likely that if you leave it in the breast, you will at some point develop invasive cancer.
2. How much of it is there? If you have a large area of DCIS, there are more cancer cells there, and thus a greater chance for one of those cells to start invading.
3. How much life to you expect to have left? The more time you let DCIS stay in your breast, the higher the risk for developing invasive disease, as you are giving it time to grow.
4. Is it hormone sensitive and are you premenopausal? If it is sensitive to estrogen and progesterone and you are still having menstrual cycles, then you are stimulating the cancer cells to grow.
So, if you are 40 year old woman with high grade comedo type DCIS, regardless of the size, I would say that it is in your best interests to remove whatever DCIS is there, as there is high risk that you will develop invasive breast cancer, probably sooner than later. If you are 70 year old woman a small area of calcifications that showed low grade DCIS and you have diabetes and heart disease, the DCIS is probably not going to do you in before your diabetes and heart disease will.
And if you are somewhere in between? It may not be so clear cut. You will have to ask your doctors what they think the likelihood that your DCIS will be come invasive is. Then you will have to decide, “Do I want to wait to see if this will become invasive cancer, or, do I want to remove these cells now and not give them a chance to become invasive.” Most people would probably opt for the latter. Perhaps the point Peggy is making is that we should be giving people the option, which is not something I am against. It is okay not to treat DCIS as long as you understand the risks.
However, treating DCIS is reducing your risk for developing invasive breast cancer in the future. Should it be grouped together with invasive cancers in the statistics? Maybe not. Should it even be considered a cancer? Maybe not. (It should be called pre-cancerous in the least.) To say that we are “over treating” DCIS is a matter of opinion. Perhaps it should be looked at as a preventative measure rather than treatment. It may be one of the few things you can do to reduce your risk of dying from breast cancer. If someone chooses to do that, I ask, “What is so wrong with that?”