Breast Cancer Treatment Options and Side Effects

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Treatment options for breast cancer depend on the cancer stage, cell type, and the person’s age and general health. Treatments include:


Surgery is the most common treatment for breast cancer. As with other types of surgery, side effects include pain or discomfort, risk of infection and some mobility restrictions right after surgery. There are two main types of surgery:

  • Lumpectomy - This operation is also called breast-sparing surgery, breast-conserving surgery, and segmental or partial mastectomy. The tumor and some surrounding tissue are removed, but not the entire breast.
  • Mastectomy - In this operation, the entire breast is removed. Often, the surgeon removes lymph nodes under the arm as well. After surgery, some people also undergo radiation therapy. Some also choose to have breast reconstruction or plastic surgery to rebuild the shape of the breast.

Radiation Therapy

Most people receive some form of radiation therapy after surgery (also called "adjuvant" therapy - meaning after surgery). The side effects depend on dose and frequently include irritation and fatigue. Bras and other clothing may rub the treated area and cause soreness.


Chemotherapy is a drug or combination of drugs used drugs to kill cancer cells. It is usually administered intravenously (through a vein).

Drugs may include: docetaxel (Taxotere®), paclitaxel (Taxol®, Onxal™), cyclophosphamide (Cytoxan®), platinum agents (cisplatin, carboplatin), vinorelbine (Navelbine®), capecitabine (Xeloda®), liposomal doxorubicin (Doxil®), gemcitabine (Gemzar®), mitoxantrone, ixabepilone (Ixempra®), albumin-bound paclitaxel (nab-paclitaxel or Abraxane®) and eribulin (Halaven®). Their side effects vary based of the drugs used. Common ones include:

  • hair loss,
  • nausea and vomiting,
  • lowering of blood counts with resulting fatigue and infection,
  • tingling or numbness related to nerve damage,
  • weakening of the heart (this is rare), and
  • damage to the ovaries that may result in infertility or early menopause.

Hormone Therapy

Doctors use drugs that block the production or function of estrogen, which can fuel breast cancer growth. In women who have not yet entered menopause, most estrogen in the body is made by the ovaries. In women who have undergone menopause, estrogen levels are lower in general, and most estrogen in the body is made in other tissues. Different drugs are used to block estrogen in premenopausal and postmenpausal women.

Hormone therapy can include: Tamoifen, Toremifene (Fareston®), fulvestrant (Faslodex®), letrozole (Femara®), anastrozole (Arimidex®), exemestane (Aromasin®), goserelin (Zoladex®), leuprolide (Lupron®), and megestrol acetate (Megace®). The side effects of hormone therapy depend on the drug or treatment type. They are sometimes similar to those of menopause and may include hot flashes, mood changes, and vaginal dryness. Younger women may be advised to consider surgical removal of their ovaries (to reduce estrogen levels) or to take a drug that blocks the effect of estrogen. Older women often have other options, including the use of medications that specifically interrupt the production of small amounts of estrogen in various tissues.

Targeted Therapy

Drugs are now available that can target breast cancer cells, or the signals that make them grow, and kill them. These treatments can be used if your cancer has the specific markers targeted by the drug.

Targeted therapies can include: trastuzumab (Herceptin®), pertuzumab (Perjeta®), ado-trastuzumab emtansine (Kadcyla®), lapatinib (Tykerb®), palbociclib (Ibrance®) and everolimus (Afinitor®). The side effects are usually less severe than chemotherapy, but can include fever, chills, pain, weakness, nausea, vomiting, diarrhea, headaches, rashes or difficulty breathing. These side effects often decrease after the first treatment.

Clinical Trials

You or your doctor may be interested in a clinical trial. Clinical trials offer patients the opportunity to benefit from the latest treatments or combinations of treatments while helping advance our knowledge of the disease and its treatment options.

Ask your doctor if a clinical trial is right for you. The Internet offers abundant information on clinical trials but only your health care team will know if there is a possible trial for you. Each trial has specific guidelines and eligibility criteria, as well as exclusions based on prior treatments, overall health, and stage of your disease. Your doctor or nurse can explain what participating in a clinical trial will involve and how it may affect your care and daily life.