Chemotherapy for Breast Cancer

Chemotherapy for breast cancer is most commonly used as adjuvant treatment; it may also be used as the primary treatment for metastatic breast cancer or as neoadjuvant therapy for large tumors. Chemotherapy is usually given as a combination of two or three drugs, sometimes given together and sometimes given after one another (sequentially).

Most chemotherapy drugs for breast cancer are given through an injection in a vein (intravenously), with the infusion lasting 30 to 90 minutes, depending on the drug. Chemotherapy is usually given in the doctor’s office or an outpatient clinic.

Chemotherapy is given in cycles, which consist of a treatment period (usually 1 day) followed by a recovery period (usually 3 weeks). The recovery period allows the noncancerous cells in your body to repair themselves from damage caused by chemotherapy before you receive more treatment. Some cycles may be shorter or longer (such as 14 or 28 days). A typical course of treatment is four to eight cycles, but the number of cycles can vary depending on the type of treatment and the response.

Many chemotherapy drugs are available, and some may be more effective treatment options for an individual breast cancer. Learning the names of chemotherapy drugs can be challenging because some are better known by their generic name, while others are better known by their trade name (Table 1). Also, abbreviations for chemotherapy combinations can look like alphabet soup. But the abbreviations for combinations are widely used and soon become familiar to women with breast cancer (Table 2).

The NCCN has noted that some chemotherapy regimens are preferred because of their effectiveness in terms of response and survival, but other combinations are also often effective. Choosing a chemotherapy regimen involves considering not only whether there is benefit but also how much benefit in relation to the side effects. In addition, certain drugs or types of drugs may be more effective for tumors with specific characteristics. For example, anthracycline drugs (doxorubicin, epirubicin, or pegylated liposomal doxorubicin) have improved survival for women with HER2-positive tumors but not HER2-negative tumors. Researchers continue to study various combinations of chemotherapy drugs, as well as the genetic make-up of tumors, to determine which regimens offer the best chance of a long period of disease-free and overall survival for women with specific types of tumors.

As with radiation therapy, chemotherapy drugs may damage healthy cells that divide rapidly, and you will have blood drawn before each treatment session to check the level of your blood cells. Treatment may be delayed until your blood cells reach a healthier level. You should tell your doctor about side effects you have from chemotherapy. If the effects become severe, another chemotherapy drug may be more appropriate and you can feel better during treatment.

For women receiving chemotherapy for late-stage cancer, the disease response to treatment will be evaluated to ensure that the chemotherapy regimen is effective. If it is not, your doctor will select another regimen for second-line therapy. The chemotherapy regimen can also be changed if breast cancer recurs during adjuvant treatment for early-stage cancer.

Table 1. Names of Chemotherapy Drugs
 

Table 2. Chemotherapy Options for Breast Cancer
 

• American Cancer Society: www.cancer.org, Detailed Guide to Breast Cancer; Breast Cancer Profiler Tool(decision-making tool)
• ASCO's patient Web site: www.cancer.net, Breast Cancer Treatment
• Breastcancer.org: www.breastcancer.org, Treatment and Side Effects
• Susan G. Komen for the Cure: www.komen.org, Understanding Cancer: Treatment

• Capecitabine (Xeloda) for Early Stage Breast Cancer and Colorectal Cancer
• Melissa Etheridge and Her Experience with Chemotherapy
• New Drugs for Aggressive Breast cancer