The American Society of Clinical Oncology (ASCO) has put out new guidelines on treating women diagnosed with advanced-stage, HER2-positive breast cancer. One set of guidelines focuses on treatments when the cancer has metastasized to the brain and the other focuses on systemic treatments. Unlike local treatments, which focus on the area or areas where the cancer was found, systemic treatments are treatments that involve the entire body. For example, radiation is a local treatment, while chemotherapy is a systemic treatment.
The guidelines were published online by the Journal of Clinical Oncology on May 5, 2014. Read the abstracts of:
- “Systemic Therapy for Patients With Advanced Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: American Society of Clinical Oncology Clinical Practice Guideline”
- ”Recommendations on Disease Management for Patients With Advanced Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer and Brain Metastases: American Society of Clinical Oncology Practice Guidelines”
ASCO is a national organization of oncologists and other cancer care providers. ASCO guidelines give doctors recommendations for treatments that are supported by much credible research and experience.
HER2-positive breast cancers have too many copies of the HER2/neu gene, which make too much of the HER2 protein. The HER2 protein sits on the surface of cancer cells and receives signals that encourage the cancer to grow and spread. About one out of every four breast cancers is HER2-positive.
In the last two decades, a number of new medicines have come on the market to treat HER2-positive disease, including:
- Enhertu (chemical name: fam-trastuzumab-deruxtecan-nxki)
- Herceptin (chemical name: trastuzumab)
- Tykerb (chemical name: lapatinib)
- Perjeta (chemical name: pertuzumab)
- Kadcyla (chemical name: T-DM1 or ado-trastuzumab emtansine)
The ASCO experts based the new guidelines for systemic treatments on a review of research published between January 2009 and October 2012. Key recommendations are:
- A combination of taxane chemotherapy plus Herceptin and Perjeta should be used as the first treatment for advanced-stage HER2-positive breast cancer, unless a person has congestive heart failure or other serious heart problems.
- If the breast cancer is also hormone-receptor-positive, hormonal therapy may be given in combination with Herceptin and Perjeta instead of chemotherapy as the first treatment.
- If the cancer grows during treatment with Herceptin and Perjeta, Kadcyla should be the next targeted therapy used.
- If a person is being treated with a combination of chemotherapy and targeted therapy, the chemotherapy should be given for about 4 to 6 months (or longer) as long as the cancer is responding to the treatment. When chemotherapy stops, a woman should continue to get targeted therapy until the cancer grows or side effects become unacceptable.
- If the cancer grows while being treated with Herceptin, Perjeta, or Kadcyla, then Tykerb or a combination or Tykerb and Herceptin should be the next treatment tried.
Brain metastases treatments
The ASCO experts couldn’t find any studies that met their criteria, so they developed a set of recommendations and then had them reviewed by two sets of outside experts. Key recommendations are:
- For people with a favorable prognosis and four or fewer brain metastases, treatment options include surgery and/or radiation. The radiation can be stereotactic radiosurgery (a form of radiation therapy that focuses high-power energy on a small area of the body; despite its name, radiosurgery isn’t surgery and cuts are not made on your body), whole-brain radiation therapy, or fractionated stereotactic radiotherapy (the doses of stereotactic radiation are divided into several smaller doses that are given on separate days).
- For people with a poor prognosis, treatment options include surgery, whole-brain radiation therapy, systemic therapies -- including Tykerb and the chemotherapy medicine Xeloda (chemical name: capecitabine) -- supportive care, palliative care, and enrolling in a clinical trial.
Editor’s Note: ASCO published an update to these guidelines in April 2018 but made no meaningful changes to the recommendations. This article was updated on Jan. 21, 2020, with updated information on medicines that treat HER2-positive breast cancer.