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Breast cancer

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Treatment of breast cancer

Treatment for breast cancer is given by cancer specialists (oncologists). Some specialize in surgery, some in radiation therapy and others in chemotherapy (drugs). These doctors work with the person with cancer to decide on a treatment plan.

Treatment plans are designed to meet the unique needs of each person with cancer. Treatment decisions for breast cancer are based on:

  • the stage of the breast cancer
  • if the woman has reached menopause
  • the hormone receptor status of the cancer
  • the HER2 status of the cancer
  • the risk for recurrence (with early stage breast cancer)
  • the overall health of the woman
  • the woman's personal decision about certain treatments

Treatment options for breast cancer

  •  surgery
    • In most cases, a woman will be given a choice of what type of breast surgery she would prefer:
      • breast-conserving surgery, followed by radiation therapy
      • modified radical mastectomy
    • Other surgical procedures that may be done include:
      • axillary lymph node dissection
      • sentinel lymph node biopsy – offered in certain situations
  • radiation therapy
    • External beam radiation therapy is always given after breast-conserving surgery. It is sometimes given after a mastectomy.
    • Systemic radiation therapy may be offered for women with breast cancer that has spread to large areas of the bone (bone metastases).
  • chemotherapy
    • Chemotherapy is offered for breast cancer that is:
      • early stage with a high risk of recurrence
      • locally advanced, advanced or recurrent
    • The chemotherapy drugs used depend on the stage of breast cancer.
    • Chemotherapy may include a combination of drugs or single chemotherapy drugs.
    • Most breast cancer is treated with an anthracycline, a taxane or both types of drugs.
  • hormonal therapy
    • Hormonal therapy is offered for hormone receptor–positive breast cancer (ER+, PR+ or both) that is either:
      • early stage with a low risk of recurrence
      • locally advanced, advanced or recurrent
    • The type of hormonal therapy offered will depend on whether or not the woman has reached menopause.
  • biological therapy
    • The type of biological therapy offered will depend on the HER2 status of the breast cancer.
    • Colony-stimulating factors may be offered to lessen the side effects of chemotherapy.
  • bisphosphonates
    • Bisphosphonates may be offered for bone metastases.
  • follow-up after treatment is finished
    • It is important to have regular follow-up visits, especially in the first 5 years after treatment.

Clinical trials

Clinical trials investigate better ways to prevent, detect and treat cancer. There are many clinical trials in Canada that are open to women with breast cancer. For more information, go to clinical trials.

See a list of questions to ask your doctor about treatment.


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