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Breast cancer

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Malignant tumours of the breast

Malignant tumours of the breast are cancerous growths that have the potential to spread (metastasize) to other parts of the body.


The most common type of malignant breast tumour is adenocarcinoma. Nearly all breast cancers start in the glandular tissue in the breast, in either the milk ducts or the milk glands. Most adenocarcinomas occur in the upper, outer part of the breast.

There are 2 main types of adenocarcinoma:

  • ductal carcinoma – begins in the lining of the milk ducts of the breast
  • lobular carcinoma – begins in the milk glands (lobules) of the breast

Ductal carcinoma and lobular carcinoma are also classified according to whether they are:

Other types of malignant breast tumours

There are other less common types of malignant breast tumours:


Dr Mohammad Akbari Dr Mohammad Akbari pinpointed a new breast cancer susceptibility gene.

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Establishing a national caregivers strategy

Illustration of caregivers

The Canadian Cancer Society is actively lobbying the federal government to establish a national caregivers strategy to ensure there is more financial support for this important group of people.

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