> Emerging Areas in Chemotherapy, Hormone Therapy and Targeted Therapy
This section discusses emerging areas of research in the treatment of early breast cancer, including some tools for tailoring treatment.
Learn about promising, new treatments for metastatic breast cancer.
Improving chemotherapy, hormone therapy and targeted therapy
Research is ongoing to improve chemotherapy, hormone therapy and targeted therapy for breast cancer. New therapies are under study in clinical trials. The results of these studies will decide whether these therapies become part of standard care. After discussing the benefits and risks with your health care provider, we encourage you to consider joining clinical trials of new therapies.
BreastCancerTrials.org in collaboration with Susan G. Komen® offers a custom matching service that can help you find a clinical trial that fits your health needs.
Learn more about joining a clinical trial.
Every cell in your body has genes that contain the blueprints (genetic code) for your body. Similarly, every cell in a breast tumor has genes. These genes contain the blueprints for the tumor.
Tumor profiling tests (using gene expression profiling tools) give information about the genes in cancer cells. These tests allow researchers study thousands of these genes at one time. The gene profiles of some tumors may help predict whether the cancer is more likely to recur (when cancer comes back) and metastasize (when cancer spreads to other organs) . Tumors with gene profiles showing a high risk of breast cancer recurrence or metastasis may be more likely to respond to chemotherapy than tumors with gene profiles showing a low risk.
Oncotype Dx® is the only tumor profiling tool widely used in the U.S. It tests a sample of the tumor (removed during a biopsy or surgery) and looks at a set of 21 genes. Oncotype Dx can be used to help make chemotherapy treatment decisions in some people with estrogen receptor-positive cancers who are going to have hormone therapy . At this time, other tools are mostly limited to the research setting. Researchers are working to address the technical limits of these tools.
Learn more about Oncotype Dx.
MammaPrint® is a tumor profiling test that looks at a set of 70 genes to give prognostic information for lymph node-negative breast cancers.
MammaPrint is not widely used in the U.S. It is more commonly used in Europe.
PAM50 (Prediction Analysis of Microarray 50) is a promising, new tumor profiling test that looks at a set of 50 genes to determine the molecular subtype of breast cancer (learn more). This set of genes may give more information than other tests to help identity which of these cancers have the highest risk of breast cancer recurrence and may get the most benefit from chemotherapy .
Subtypes of breast cancer
Molecular and genetic differences in breast cancers may be useful in guiding the development of new targeted therapies. Most studies divide breast cancer into four major molecular subtypes:
- Luminal A
- Luminal B
- Basal-like/triple negative
- HER2 type
Although mainly used in research setting, these subtypes may be useful in tailoring treatment in the future.
Learn more about subtypes of breast cancer.
Bone-strengthening therapy using bisphosphonates is a standard treatment for women with bone metastases (more). Bisphosphonates are also used to help prevent bone loss (osteoporosis) in breast cancer survivors and cancer-free women.
The role of bisphosphonates in the treatment of early breast cancer (to lower the risk of breast cancer recurrence) is under debate. At this time, there seems to be no role for bisphosphonates in breast cancer treatment for younger, premenopausal women. However, some findings suggest a benefit for older, postmenopausal women . For postmenopausal women with osteoporosis or osteopenia (low bone density), these findings may be a reason to add bisphosphonates to treatment.
Bisphosphonate use increases the risk of osteonecrosis of the jaw, a serious jawbone disorder [46-47]. So, it is important to have a full dental exam before starting treatment and to talk with your oncologist before getting any dental procedure while you are on bisphosphonates .
Poly(ADP-ribose) polymerase (PARP) inhibitors are a class of drugs under study for many types of cancer, including breast cancer. PARP is an enzyme involved in DNA repair. Some chemotherapy drugs damage DNA. Adding a PARP inhibitor to some chemotherapy plans may lower the chances that the cancer cells will become resistant to the chemotherapy. This is most often a problem for those with metastatic breast cancer.
PARP inhibitors are under study for the treatment of breast cancers related to BRCA1 and BRCA2 gene mutations .
At this time, data on PARP inhibitors and breast cancer are limited and are not conclusive. Although some results look promising, these drugs are in the early stages of study and are only available in clinical trials.
Read comments on the potential uses of PARP inhibitors from our Chief Scientific Advisor, Dr. Eric Winer.
CYP2D6 and tamoxifen
CYP2D6 is an enzyme that affects how the body metabolizes (breaks down and uses) certain medications. For this reason, researchers were interested in whether certain forms of the gene related to CYP2D6 function affected the hormone therapy tamoxifen. The largest studies to date have found no difference in the risk of breast cancer recurrence in women with gene variations related to less CYP2D6 function compared to risk in women with genes related to normal or high CYP2D6 function [49-50]. There is no role for routine testing of CYP2D6 in women taking tamoxifen.
Certain medications can interfere with CYP2D6 function and should be avoided while taking tamoxifen . For example, some antidepressants, such as fluoxetine (Prozac), buproprion (Wellbutrin) and paroxetine (Paxil), can interact with CYP2D6 and may affect how tamoxifen works in the body . If you are considering taking tamoxifen, talk to your health care provider about potential drug interactions.
Learn more about tamoxifen.
Immunotherapy is a promising, new field of breast cancer treatment that uses the body's immune system to fight cancer. There are many types of immunotherapy under study, including the use of vaccines.
Like vaccines that protect against the flu or measles, cancer vaccines are designed to build up the body's immunity against disease. Cancer vaccines may be made up of cancer cells or parts of cancer cells. These cells stimulate the body's natural defenses, helping it to attack and kill cancer cells.
Still in early stages of development, cancer vaccines could one day be used to treat early breast cancer . Clinical trials of vaccines for breast cancer are underway.
High-dose chemotherapy/bone marrow transplant
High-dose chemotherapy (sometimes called bone marrow transplant) was an experimental therapy that used high doses of drugs to try and kill a large number of cancer cells. However, findings from randomized clinical trials showed that high-dose chemotherapy was no more effective than standard dose chemotherapy and was fatal in about six percent of people [53-55]. It is no longer used to treat metastatic breast cancer and should only be considered in the context of a clinical trial. .
After talking with your health care provider, we strongly encourage you to consider joining a clinical trial of new therapies. BreastCancerTrials.org in collaboration with Susan G. Komen® offers a custom matching service that can help you find a clinical trial that fits your health needs.
Learn more about clinical trials and find a list of resources to help you find a clinical trial.
Meet Bonnie Olson, a breast cancer survivor who participated in a clinical trial.
Our commitment to research
At Susan G. Komen®, we are committed to ending breast cancer forever by energizing science to find the cures and ensuring quality care for all people, everywhere. Our global research grants and scientific programs are essential driving forces for achieving this mission. Many of the world’s leaders in breast cancer research have been supported by Komen’s Research and Scientific Programs – including three Nobel Laureates. Komen’s funding has supported research that has resulted in a better understanding of breast cancer; earlier detection; personalized, less invasive treatments for what was once a “one-treatment-fits-all” disease; and improved survival rates. Learn more about the exciting research we are funding.
*Please note, the information provided within Komen Perspectives articles is only current as of the date of posting. Therefore, some information may be out of date at this time.