Rutgers oncologist says less is more when it comes to breast cancer treatments
The major advance that has been made in breast cancer is understanding that breast cancer is not just one disease but rather a spectrum of diseases.
That is due to the understanding of the different molecular profiling of different cancers that have informed the discovery and development of new drugs and has changed the natural history of the disease, said Dr. Deborah Toppmeyer, chief of medical oncology at Rutgers Cancer Institute of New Jersey.
Breast cancer is divided into subclasses which then need to be treated differently, she said.
Within those subclasses, there are drivers such as the type of breast cancer that overexpresses the HER2 oncogene which has led to several new therapies that target that specific type of breast cancer, she said.
These antibody-drug conjugates have changed the history of the disease.
Why is the "less-is-more" approach to breast cancer best?
“It’s through the understanding of the molecular differences between the different types of breast cancer that has allowed us to make this kind of progress,” Toppmeyer said.
There are very few cases where bilateral mastectomies are necessary, she added. However, it is important to know that whether we’re talking about surgery or systemic treatment of breast cancer, less is more.
“We have gone from years and years ago from radical mastectomies to really doing lumpectomies with sentinel node biopsy, and that’s just taking a few lymph nodes underneath the armpit and in certain cases, not even looking at the sentinel nodes,” she said.
The most important aspect of the treatment of breast cancer is a systemic treatment.
Doing more locally does not necessarily change what happens to a patient in terms of their overall survival.
“That doesn’t mean you don’t want to do a complete cancer operation but I think the definition of what that complete cancer operation is now, has evolved,” Toppmeyer said.
Doing less means fewer side effects. Not doing a full axillary lymph node dissection, which used to be done years ago, has reduced the risk of women developing lymphedema of the arm, which is a complication of surgery and/or the addition of radiation therapy, she explained.
“We’re finding we can achieve the same result doing less and radiating a little bit differently, rather than doing more surgery,” Toppmeyer said.
This is a result of very well-designed clinical trials that ask the question, “Do we need to do more?”
Fewer women are receiving chemotherapy today because there is a special test that can be done on the tumor called Oncotype that allows doctors to see who are the patients who will benefit from chemo and who are those patients who will benefit from taking a hormone-blocking pill.
Becoming more targeted in breast cancer treatment has become evolutionary. It’s important to know the situations where less therapy can be given and achieve the same excellent result at the same time, whether that be surgical, with radiation, or with systemic therapy, she said.
Are breast cancer patients living longer with these advances?
The survival rate is getting better with advances, Toppmeyer said. That’s because of earlier detection and better therapies and more targeted therapies.
Toppmeyer did note that there is one subtype of breast cancer called “triple negative breast cancer” that does not have a good target. It is more typically seen in younger women, in young Black women, and in women with BRAC mutations.
“But we now know that immunotherapy plays a critical role in the early treatment of breast cancer in this particular subclass of breast cancer. This has been a significant advance for this particular subtype where we didn’t have a lot of good weapons as opposed to tumors that are driven by estrogen or tumors that overexpress the HER2 oncogene,” Toppmeyer said.
While a good cancer operation is needed, doctors need to be much more strategic and targeted to a specific patient who has a specific tumor that can be very different from the next woman’s breast cancer.
“The molecular tools that we have now have opened the door to understanding how we treat those individuals, and because of that, women are living longer, with less toxicity,” she summed up.