An exciting development, but more work needed
We’ve known for some time that breast cancer was more than just one disease. Currently, we think of it as divided into five or six categories, and we classify it and treat it according to whether the tumor responds to estrogen or is HER2-positive. In the future, the findings from a new study that divided cancers into subtypes based on their genetic fingerprints may make it possible for us to develop new treatments and new treatment strategies.
The study, the largest gene study of breast cancer tissue to date, was carried out by scientists at Cancer Research UK’s Cambridge Research Institute, in collaboration with the BC Cancer Agency Vancouver Canada. It involved analyzing the DNA and RNA2 of 2,000 tumor samples taken from women diagnosed with breast cancer between five and 10 years ago.
Using the tumor’s genetic fingerprints, the study revealed 10 subsets of breast cancer. The researchers were also able to identify new genes that drive breast cancer and the relationship between these genes and the known cell signaling pathways that control cell growth, which could lead to the development of new, targeted breast cancer treatments.
Dividing breast cancer into 10 categories has the potential to make treatment more precise than it is today. But it will probably be some time before we know if this is indeed the case and if the researchers are able to develop new targeted therapies that work better than the treatments currently used.
I know that some women may be concerned that this new development means that our current method isn’t good, or that they may have been told they have a good prognosis based on the methods we use today OncotypeDX, estrogen-receptor status, andHER2-status but really don’t. Based on what we now know, I don’t think that will be the case.
It’s important to remember that breast cancer treatment is always a work in progress. The Oncotype DX test has made it possible for us to get more information about which tumors will respond well to hormone therapy alone and which should be treated with hormone therapy and chemotherapy, and I expect that we will see new tests that build on this in the years to come.
It will be wonderful if this new information helps us to determine which tumors are so slow-growing that they really don’t need to be treated at all, as it will allow us to keep women from having to experience the side effects associated with surgery, radiation, chemotherapy, and hormone therapy. Getting the information that a tumor is very aggressive will only help us if we can figure out new and better treatments to fight the disease. But what we really need to do is figure out what causes this disease so that we can end it.