Treatment of breast cancer may be dependent on the type recommended by your doctor. Sometimes people with the same cancer may be given different treatments. You and your doctor will consider these factors to determine which type of treatment will be administered:

  • Type of cancer
  • Stage of cancer
  • Other characteristics of the cancer, such as its grade
  • Your personal situation and wishes

Breast cancer treatments can be broadly categorized into the following types of therapies:

  • Local (surgery and radiation)
  • Systemic (chemotherapy, hormone therapy and targeted therapy)

Local treatments

Surgery and radiation therapy are local treatments because they treat a small area of the body.

Surgery to remove the cancerous tissue is the most common form of treatment. There are two types of surgery: lumpectomy and mastectomy. Often surgery is used along with chemotherapy, radiation therapy, hormone therapy or targeted therapy.

  • Lumpectomy involves the surgical removal of the cancerous tumour in the breast and some surrounding normal tissue. Usually underarm lymph nodes or a sample of nodes are also removed. Radiation is almost always used to decrease the chance of recurrence. For more information, see Lumpectomy: What to expect at home (
  • Mastectomy involves surgical removal of the entire breast containing the breast cancer. Underarm lymph nodes or a sample of nodes are also removed. Studies have shown that lumpectomy and mastectomy are equal in effectiveness. Radiation may not be required. For more information, see Mastectomy for Breast Cancer (

Radiation Therapy uses high-energy X-rays to destroy any cancer cells that may remain in the breast after surgery. This reduces the chance of recurrence.

Systemic treatments

Chemotherapy, hormone therapy and targeted therapy are systemic because they target your whole body. They are used to get rid of or disable cancer cells that may have spread from the breast to other areas of the body.

Chemotherapy uses drugs to stop the growth and spread of cancer cells throughout your body. Its aim is to lower the risk of secondary cancer. It can be given before or after surgery.

Hormone Therapy uses drugs to block the production of estrogen and other female hormones that promote the growth of certain kinds of cancer cells after surgery. It may also involve taking a drug, such as tamoxifen, over the course of a few months or years. Read about potential side effects of hormone therapy (Canadian Cancer Society).

Tamoxifen is commonly used to treat hormone-sensitive breast cancer in its early stages. Side effects can include weight gain and menopausal symptoms like hot flashes.

Targeted Therapy is a new treatment approach that targets the genes and proteins in the cancer cells in an effort to stop their growth and spread. When certain cells are blocked, the cancer cannot grow. As of now, Herceptin (trastuzumab) is the only widely available form of targeted treatment for early breast cancer. It is most commonly used in women with HER2+ breast cancer.

Treatment for pregnant women

Treatment decisions for breast cancer during pregnancy are based primarily on:

  • The stage of breast cancer
  • The age of the fetus

Once the preliminary pathology report is compiled, the healthcare provider and the patient will determine which method of treatment is the most beneficial for the patient’s specific case.

The following treatments are offered to pregnant women:

  • Surgery
  • Chemotherapy
  • Radiation
  • Hormone therapy
  • Biological therapy

See these webpages for more information:

Treatment of metastatic breast cancer

You may feel scared, angry, sad, in disbelief, or overwhelmed. Although metastatic breast cancer is considered incurable, it is important to know is that there are many treatment options which can control the disease for extended periods of time and allow people to live with a good quality of life, and in many cases, for many years.

Goals of treatment for early stage breast cancer in comparison to treatment of metastatic breast cancer are very different. Treatment for metastatic breast cancer may seem less aggressive than treatment for early stage breast cancer. Currently, there is no cure for metastatic breast cancer – treatment focuses on controlling the disease, easing symptoms, while trying to minimize treatment side effects and maintain quality of life.

Each person with metastatic cancer will have a treatment plan designed for them by their healthcare team. They will recommend treatment based on the characteristics of the cancer and your unique needs (via Canadian Cancer Society). Treatment of metastatic cancer depends on many factors, including:

  • where the cancer first started (primary site)
  • where the cancer has spread – the number, size and location of metastases
  • the person’s age and overall health
  • previous treatment

Your health care provider will offer the following treatment options for metastatic breast cancer. Speak to your health care team to learn about benefits, limitations and side effects of each option.

Systematic treatments for metastatic breast cancer

Hormone Therapy – Metastatic breast cancer that is hormone receptor positive may be treated using hormone therapies such as anti-estrogen medications, aromatase inhibitors, or ovarian suppression. The goal of treatment is to shrink or slow the growth of the tumour(s) by blocking the production of estrogen or its effects on tumour growth. The type of treatment prescribed will depend on how the original cancer responded to hormone therapy before, and whether or not you have gone through menopause.

Chemotherapy – a treatment method that uses medication to destroy cancer cells. Like hormone therapy, chemotherapy is a systemic treatment that takes effect on the whole body. The goal of chemotherapy in the treatment of metastatic breast cancer is to try to shrink or slow the growth of the tumour(s).

HER-2 Therapy –Trastuzumab (Herceptin) is a medication that binds to and blocks HER-2 receptors, and may be used to treat metastatic breast cancers that are HER-2 positive. The goal of trastuzumab in the treatment of metastatic breast cancer is to try to shrink or slow the growth of the tumour(s).

Local treatments for metastatic breast cancer

Radiation therapy – radiation therapy may be used to help reduce pain and alleviate symptoms and/or used to shrink tumours to help lessen pain and discomfort.

Surgery – Surgery to remove metastatic breast cancer is not usually done. However, sometimes surgery is recommended to lessen serious side effects that can occur when cancer has metastasized to the brain or bones in the spinal column.

A time will come when the metastatic cancer will no longer respond to treatment, or you make the decision to stop treatment to focus on the best quality of life possible. At this point, palliative care takes a greater role in your journey to focus on providing comfort, lessening symptoms and pain you may be experiencing, and providing professional support, and enjoying this time with your loved ones. Learn more about palliative care.

Frequently Asked Questions (FAQs)

Are clinical trials safe and effective? Clinical trials are research studies that test new ways to prevent, detect, treat or manage cancer or other diseases. Clinical trials provide information about the safety and effectiveness of new approaches to see if they should become widely available. Most of the standard cancer treatments used today were first shown to be effective through clinical trials.

Is treatment any different if you are a man battling breast cancer? According to the Canadian Cancer Society, men with breast cancer often receive the same type of treatment as post-menopausal women with breast cancer and surgery is the most common treatment for breast cancer in men.

Breast Conserving Surgery or Mastectomy? An overview of advantages and disadvantages of breast conserving surgery in comparison to a mastectomy.