Breast cancer diagnosis

Breast cancer is usually found in one of three ways

When you tell your doctor about an unusual thickening or lump, or a change in the appearance of your breast or nipple.

When your doctor finds a change.

Through screening mammography.

Most breast lumps are not cancer but your doctor will arrange special tests to confirm the diagnosis. They include: Imaging studies.

X-rays, ultrasound, CT scans (computerized axial tomography), MRIs (magnetic resonance imaging) and bone scans allow tissues, organs and bones to be examined in more detail. In the case of breast cancer, a diagnostic mammogram (a special x-ray of breast tissue) will be done. It may be uncomfortable but is usually painless.

Biopsy

A biopsy is usually necessary to make a definite diagnosis of cancer. Cells or tissues are removed from the body and checked under a microscope. If the cells are cancerous, they may be studied further to see how fast they are growing.

There are many ways to do a biopsy. A breast biopsy can be done

With a special needle, under local anesthetic (fine-needle aspiration)

With a thicker needle under ultrasound guidance.

During a mammography (core needle biopsy)

If cancerous cells are found, they are tested to find out what kind of breast cancer it is and if it has hormone receptors (estrogen or progesterone).

Testing will also identify the grade of your cancer cells. Low grade cells are slower to divide and the cancer is generally less aggressive. Higher grade cells divide more quickly and the tumour is more likely to spread.