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Patient Education: Diseases Conditions Treatments & Procedures

Breast Cancer

How is it Diagnosed?

Breast cancer can be suspected by finding a new lump or other abnormality in your breast or a new abnormality on a routine mammogram.

A lump in the breast can be found during a routine exam by a doctor or nurse or by you inspecting your own breasts. Either way, further investigation is needed to determine what the lump is. The first thing to be done is a diagnostic mammogram and/or a breast ultrasound. If these tests show an area of concern in the breast, your physician would arrange for a biopsy. The biopsy will give specific information on whether the lump is cancerous or benign (not cancerous).

Another way that breast cancer may be diagnosed is during a routine screening mammogram. The radiologist will compare the new mammogram to your old mammograms and may see a new area of concern such as new calcium deposits or a mass. Additional images of the breast would be taken and if there remained any concern about the possibility of cancer, a biopsy would be performed to determine if this lesion of concern is cancerous or benign.

If the biopsy shows cancer, a referral is made to a surgical oncologist to determine what type of surgery is needed. This is very important as surgery will aim to remove the area of concern and also give the team more information to help them decide how to best treat your breast cancer.

These tests may be done to help diagnose breast cancer:

  • Diagnostic mammogram: This is an x-ray of the breast. A mammogram can find breast cancer before you or your doctor is able to feel it in your breast. The mammogram may also find calcium deposits within your breast that are sometimes related to breast cancer.
  • Breast ultrasound: This test is done to determine if any lumps felt by your doctor are solid (like a tumor) or fluid-filled (like a cyst). This is usually done along with a diagnostic mammogram.
  • MRI of the breast: Magnetic Resonance Imaging is sometimes used to find a breast cancer that cannot be seen clearly by ultrasound or mammogram. MRI is not routinely done to diagnose breast cancer but may be recommended by your physician based on your personal profile or your mammogram or ultrasound results.
  • Digital mammogram: uses newer technology to look at x-rays of the breast using electronic images instead of film. The advantage of a digital mammogram is that the images can be directly stored on a computer and the radiologist can use specialized software to look more closely at areas of concern within the breast. Digital mammograms have been found to be particularly useful in women under 50 or women with extremely dense breasts.
  • Core Biopsy of the breast: This is a test that will tell your physician if there are breast cancer cells within the lump in your breast or in the lymph nodes under your arm. The procedure is done by using a needle to take a sample of tissue (at the site of where the lump or abnormal lymph nodes were seen by the mammogram or breast ultrasound) and putting the tissue under a microscope where it can be carefully looked at by a pathologist.

Visit the Breast Care Group at Odette Cancer Centre