Recurrent breast cancer grows during treatment or comes back after a remission. If you are facing a recurrence of breast cancer, the important thing to keep in mind is there is no reason for despair or hopelessness. Many women who are treated for recurrent breast cancer enjoy long and productive lives following a recurrence.
Breast cancer can recur almost anywhere in your body. But common places include your liver, bones, lungs, brain, and skin. Treatment for recurrent breast cancer depends on which treatments you had before, the characteristics of the tumor, and where the cancer has recurred. Rest assured, though, there are many treatment options available to you.
This is recurrence of breast cancer that is only in your breast or the nearby area. This is typically treated with surgery with or without radiation therapy. Additional systemic therapy may be considered in certain patients.
This is recurrence of breast cancer in other parts of your body. Most recurrences are distant ones. When the cancer has spread to other parts of your body, it is also called metastatic breast cancer. Distant recurrences are treated with systemic treatment. This is treatment that can reach the cancer anywhere in your body. It may include chemotherapy, antihormonal therapy, and targeted therapy.
To determine the treatment that's best for you, careful imaging tests (mammography, CAT or PET scans, MRIs, ultrasound, and if necessary, chest x-rays) also are very important to determine exactly where the cancer is located.
The following is a general overview of treatment for recurrent breast cancer. Using two or more types of therapies—called multimodality treatment—is increasingly recognized as a beneficial approach. Participating in a clinical trial of new, innovative therapies also may provide the most promising treatment and is something you may want to discuss with your health care provider. The benefits and risks of each treatment and of participation in a clinical trial must be carefully weighed.
Treatment of a Local-Regional Recurrence of Breast Cancer
After initial treatment of your breast cancer with mastectomy or breast-conserving therapy (a lumpectomy plus radiation therapy), you may have a local recurrence. This is defined as cancer recurring in the same breast, in your chest wall (your chest muscles and ribs), or in the skin over your breast. You may also have a regional recurrence of cancer. This is defined as cancer recurring in the lymph nodes above your collarbone, in your chest, or in your armpit (axilla).
Recurrence After Mastectomy
Recurrence After Mastectomy
A local recurrence of breast cancer after initial treatment with a mastectomy may be effectively controlled with more radiation therapy. Surgery before radiation therapy may also be beneficial in some cases. It may be possible to prevent more local recurrences depending on the size of the cancer, the amount of radiation given, and the amount of tissue irradiated.
Despite surgery and radiation, the majority of women who have a local recurrence later have a recurrence somewhere else in their body. For this reason, many doctors believe additional treatment with chemotherapy, targeted therapy, or antihormonal therapy may be useful.
Recurrence After Breast-Conserving Therapy
A recurrence after breast-conserving therapy that is only in the local-regional area around the original cancer is typically treated with a mastectomy. Mastectomy may be followed by radiation therapy in some cases. Women who have a regional recurrence of breast cancer are at a higher risk for having the cancer come back somewhere else in their body. They may benefit most from the addition of radiation therapy or another treatment.
Systemic Treatment of Recurrent Breast Cancer
Targeted therapies - target only cancer cells and minimize damage to normal, healthy cells. This means that side effects of these therapies are generally milder. Available targeted therapies can be easily combined with chemotherapy. Advances in science and technology have led to the development of several different types of targeted therapies. The therapies currently in use include:
- Herceptin® (trastuzumab) - Many targeted therapies work by targeting a protein, or receptor, that is present in high levels on the surface of cancer cells. HER2 (human epidermal growth factor receptor 2) is a protein that is overexpressed (present in greater quantities than normal) in about one in four women with breast cancer. HER2 stimulates the uncontrolled growth and replication of the cancer cells. It does this by binding only with other proteins (called growth factors) in the blood.
- Avastin® (bevacizumab) - This is a new type of targeted therapy. It stops a process called angiogenesis (the development of new blood vessels). Cancer cells require food, oxygen, and proteins to grow and spread. They need new blood vessels to deliver these essentials. Bevacizumab binds to a protein called vascular endothelial growth factor (VEGF). VEGF is important for growing blood vessels to the cancer. The binding of bevacizumab to VEGF reduces this activity. This drug is not yet approved by the U.S. Food and Drug Administration for treatment of breast cancer.
- Tykerb® (lapatanib) - an oral, small molecule dual kinase inhibitor of HER1 and HER2. It appears to have similar activity to single agent trastuzumab and enhances the activity of Xeloda® (capecitabine) when given in combination to women with metastatic breast cancer. Lapatanib may also fight tumors in patients with brain metastases.
Chemotherapy - Many women with recurrent cancer have typically already received adjuvant chemotherapy as part of their initial treatment. The first chemotherapy treatment for metastatic disease is typically called first-line therapy. Additional chemotherapy for cancer that has recurred is referred to as second-line therapy.
Except in instances where the initial treatment may have been inadequate, second-line chemotherapy and beyond is typically associated with lower response rates and a shorter duration of benefit than first-line therapy. Thus, the goal of second-line chemotherapy is to reduce symptoms, improve quality of life, and increase survival time.
The type of second-line chemotherapy that is selected and its effectiveness depend on which first-line chemotherapy you received. In particular, whether or not your previous chemotherapy contained an anthracycline—Ellence® (epirubicin), Adriamycin® (doxorubicin)—or a taxane—Taxol® (paclitaxel) or Taxotere® (docetaxel)—helps determine your options for second-line therapy.
Typically, your cancer becomes resistant to drugs that were previously used to treat it. However, in certain circumstances, an alternative way of administering a drug previously used in treatment, or an alternative drug in the same class of drug, may prove useful.
For example, if you were already treated with a taxane (paclitaxel or docetaxel) and anthracycline, your chemotherapy options now include Abraxane® (NAB paclitaxel), Gemzar® (gemcitabine), capecitabine, and Navelbine® (vinorelbine), as well as alternative ways of delivering taxanes.
NAB paclitaxel - This drug uses a new method to deliver paclitaxel. It uses albumin, the most abundant protein in your body, to take the paclitaxel directly to cancer cells. Albumin is a blood protein that your body uses to transport nutrients and energy to tissue. Once the albumin reaches the tissue, it is taken in. There it delivers its cargo to the surrounding cells. In the case of NAB paclitaxel, that cargo is the drug paclitaxel.
NAB paclitaxel has several advantages over regular paclitaxel. Typically, paclitaxel is administered with a toxic chemical solvent in addition to the active drug. With NAB paclitaxel, no solvent is required and about 50 percent more drug can be given.Thus, a more active drug gets into the cancer cells with fewer side effects.
Gemcitabine - Studies indicate that gemcitabine is effective in the treatment of recurrent breast cancer that has previously been treated with a taxane.
Capecitabine - A chemotherapy drug you take as a pill. You can take it at home for treatment of breast cancer. Research indicates that 20 percent to 30 percent of women have a measurable shrinkage of their cancer after treatment with capecitabine.
Vinorelbine - A drug taken orally or by injection. It interferes with the growth of cancer cells.
Antihormonal therapy - The hormone estrogen makes some breast cancers grow. So the aim of antihormonal therapy as a treatment for breast cancer is to block or prevent cancer cells from being exposed to estrogen.
Estrogen is a female hormone made by your ovaries and other tissue. It serves many critical functions in your body. These include developing your female sex organs in puberty, preparing your breasts and uterus for pregnancy in adulthood, and maintaining your cardiovascular and bone health. Without estrogen, your body cannot sustain pregnancy and is susceptible to heart disease and osteoporosis (thinning of your bones).
Estrogen can also make some cancers grow. Your breasts, uterus, and other female organs are made of cells that are stimulated to grow when exposed to estrogen. These cells have areas on their surface called estrogen receptors. Estrogen in your blood binds to these receptors and stimulates the cells to grow.
When cells that have estrogen receptors become cancerous, exposure to estrogen increases the cancer's growth. Cancers that have estrogen receptors are called estrogen receptor-positive (ER-positive) cancers. The growth of ER-positive breast cancer cells can be prevented or slowed by reducing their exposure to estrogen.
This is the goal of antihormonal therapy for breast cancer. But reducing estrogen levels can also have side effects. This happens because estrogen is necessary for important body functions, such as bone growth and cardiovascular health. Lower estrogen levels lead to thinner bones and heart disease.
Many postmenopausal women with ER-positive breast cancer are initially treated with tamoxifen. This drug is a type of antihormonal therapy. It works by blocking estrogen from entering a cell by binding to the cell's estrogen receptors.
A newer group of drugs called antiaromatase drugs or aromatase inhibitors—have been developed for use in postmenopausal women. They appear to be more active than tamoxifen. Antiaromatase drugs work by stopping the formation of estrogen in your body. Aromatase is the enzyme that helps convert estrogen to its active form. Antiaromatase drugs inhibit aromatase. As a result, the level of active estrogen in your body falls.
Treatment of recurrent, hormone-resistant breast cancer may differ based on which treatment you had previously.
Antihormonal Therapy After Tamoxifen
Research suggests that aromatase inhibitors are the best option after a woman who has been on tamoxifen develops metastatic breast cancer. These drugs, which include Femara® (letrozole), Arimidex® (anastrozole), or Aromasin® (exemestane), are also chosen over tamoxifen as a first-line therapy for metastatic breast cancer.
Specifically, studies have found that:
- Treatment with exemestane after 2 to 3 years on tamoxifen improves cancer-free survival time more than continuing tamoxifen in ER-positive breast cancer.
In postmenopausal women with metastatic breast cancer that had progressed after treatment with tamoxifen, treatment with fulvestrant appears to be equally as effective as, and perhaps slightly better than, anastrozole for advanced cancer that had progressed after tamoxifen therapy. Fulvestrant is administered as a shot, however, compared with tamoxifen and the other aromatase inhibitors, which are oral drugs.
If you have metastatic breast cancer that has stopped responding to one antiaromatase drug, switching to another aromatase inhibitor may help control the cancer.
Treating Bone Metastases
In recurrent breast cancer, the cancer has often spread to your bones. This can happen when cancer cells break off from the original tumor and travel in your circulatory or lymph system. Then the cells grow into another tumor. These tumors are called bone metastases. They break down the bone. This can be painful and lead to fractures (broken bones). Your doctor will likely treat your bone metastases with a bisphosphonate drug.
Bisphosphonates are a class of drugs that slow the rate of bone destruction in women with cancer. Clinical studies have shown that these drugs can prevent or delay bone destruction, including fractures and related pain, in women with breast cancer that has spread to the bone. In addition, other therapy—including radiation therapy, endocrine therapy, or chemotherapy—may be recommended.
The American Society of Clinical Oncology also recommends the use of the bisphosphonates Zometa® (zoledronic acid) or Aredia® (pamidronate) for treatment of bone metastasis from breast cancer. The optimal duration of use and the best time to take bisphosphonates are still being studied. Researchers hope that bisphosphonates may help prevent some women from getting bone metastases if these drugs are taken before the cancer spreads.
Research is in progress to refine existing treatments and develop new ones. For information on some of the techniques currently under investigation, see Strategies to Improve Treatment.
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