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Breast cancer

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If breast cancer spreads

Cancer cells have the potential to spread from the breast to other parts of the body where they can grow into new tumours. This process is called metastasis. The tumours are also called metastasis (singular) or metastases (plural). Metastases are also called secondary tumours.

Understanding the usual progression of cancer helps the doctor to predict its probable course, plan treatment and anticipate further care.

The most common sites where breast cancer spreads are:

  • regional lymph nodes (on the same side of the body as the breast cancer)
    • under the arm (axillary)
    • around the collarbone
    • around the breastbone
  • chest wall
  • skin of the breast
  • bone – the most common site of metastases
    • spine
    • ribs
    • bones of the legs
  • liver
  • lung
  • brain
  • lymph nodes far from the breast
    • in the neck
    • on the opposite side of the body from the breast cancer

Cancer-related emergencies and breast cancer

Cancer-related emergencies are serious problems that can occur because of breast cancer, especially when it spreads (metastasizes).


Paul Newcombe Volunteering during Daffodil Month is an incredibly rewarding experience, whether you have been touched by cancer or not.

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Celebrating cancer survivors at Relay For Life

Relay For Life illustration

For cancer survivors, the Canadian Cancer Society provides a unique opportunity to celebrate their courage in the fight against cancer. During hundreds of Relay For Life events across the country, thousands of survivors join together for the Survivors’ Victory Lap.

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