Date: July 1st, 2005
Gatherings of breast cancer researchers have been surprisingly upbeat events lately, as scientists are beginning to feel that maybe - just maybe - they’re making some real progress toward understanding the disease.
“It’s actually amazing,” said Jennifer Eng-Wong, M.D., M.P.H., a medical oncologist with the National Cancer Institute, a division of the National Institutes of Health. “We just had our big oncology meeting and at the end of the presentation of the studies for breast cancer, the response was overwhelming elation and applause from the audience. People are feeling like, ‘Yes - we really are making headway on this disease. We really have come a long way.’”
According to numbers released earlier this year by the American Cancer Society, breast cancer is still the most common cancer among women and incidence rates continue to rise – but more slowly than they have in the past. And several recent news stories involving breast cancer research have reported strides in treatment that may provide hope to thousands of patients.
Understanding the biology of breast cancer
While we may think of breast cancer as a single entity, the disease really comprises a number of different types of cancers, which respond differently to treatment. Physicians may recommend different courses for patients depending on whether their cancer has spread beyond where it began, or what types of cancer cells they have.
According to Dr. Eng-Wong, understanding the biology of these different types of cancers will be key to providing effective therapies, as well as preventing anyone from getting breast cancer in the first place.
“Diagnosis and understanding tumor biology is rapidly evolving,” she said. “We’re really becoming able to better understand what kind of tumors a person has and how to target them with the drugs we have available. And hopefully that will lead to a better understanding of who’s at risk for getting breast cancer as well.”
A couple of recent clinical trials have underscored the effectiveness of targeting treatment. They involved the drug trastuzumab (brand name Herceptin), which was approved to treat advanced breast cancer in 1998. And they had hopeful news for women with HER-2 positive cancer, a particularly aggressive form.
Patients with this type of cancer have cancer cells that make too much of a protein called HER-2. These tumors tend to grow faster and recur more often than those that are not HER-2 positive. Trastuzumab targets these specific kinds of cells directly. And when used in combination with a traditional chemotherapy regimen, the drug was shown to reduce the risk of recurrence by 52 percent compared with that same regimen alone.
Advanced medicine and age-old advice
While cancer researchers have made promising inroads when it comes to medical therapies, they haven’t lost sight of the potential power held by the breast cancer patient herself. They hope to know more about how lifestyle choices affect cancer so they can provide specific guidelines that go beyond “eat right and exercise.”
For instance, a recent study showed that brisk walking could have a significant impact on a woman’s chances of dying from the disease. While previous studies have demonstrated that exercise can reduce the incidence of breast cancer, this study set out to determine whether exercise improves the chances of survival once a breast cancer patient has been diagnosed – and if so, how much exercise it takes to make a difference. The women in the study who walked three to five hours a week reduced their risk of dying by 50 percent.
Another recent study showed that for women who have had breast cancer, a low-fat diet could reduce the chances that their cancer will come back. The results were not dramatic – 12.4 percent of those on the diet were disease-free after five years, compared to 9.8 percent of those on a regular diet. While scientists involved are not exactly blown away by these results, the study showed enough of an impact to merit further research and follow-up with the participants.
“I think breast cancer has really led the pack in a lot of ways, in terms of how aggressive to be in terms of treatment, and how to target therapies,” said Dr. Eng-Wong. “What we have to treat women with has grown enormously over the last four years. And we can’t cure everybody, but we can certainly keep people alive longer that have metastatic disease, and we can certainly cure more people that have early breast cancer. I think it is really encouraging overall.”