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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).


Holly Benson Thanks to good research, thanks to funding for research, I’m here and enjoying my life.

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Help for smokers trying to quit

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It’s okay to need help to quit smoking. The Canadian Cancer Society is here to support people who are ready to quit and even those people who aren’t ready.

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