Breast cancer can be diagnosed both before the development of symptoms as well as after symptoms have already appeared. Health care providers use a variety of methods to detect the presence of breast cancer.
If you notice any changes to your breasts, you should contact your doctor. Some signs to watch for include: a lump felt in the breast, nipple pain, an inverted nipple, nipple discharge (clear or bloody), sores on the nipple and areola (the small ring of color around the center of the nipple), or enlarged lymph nodes (which work as filters for the lymphatic system in the body) under the arm.
Your medical history is determined by your current symptoms, risk factors and any medical events you have experienced in the past. The medical history of your family may also be explored to help diagnose breast cancer.
A physical examination should also be performed, which could involve a clinical breast examination to check for any changes, differences or irregularities of the breast and underarm area. Any palpable lump requires further investigation.
Your physician may request further testing to be done following a physical exam and a review of your medical history.
Imaging tests are used to develop pictures of the breast tissue which can be examined for signs of cancer. Three main types of imaging are used to diagnose breast cancer.
Screening Mammography involves the use of an x-ray using a low-dose of radiation to create an image of the breast. Screening mammograms are used routinely to detect breast cancer in individuals without obvious signs or symptoms of cancer. In Canada, the Canadian Task Force for Preventive Health Care established national guidelines for breast cancer screening which recommends that women aged 50–74 schedule a mammogram every 2–3 years. For more information on these guidelines, please visit the Canadian Task Force on Preventative Health Care.
Diagnostic Mammography involves an x-ray using a low-dose of radiation to create an image of the breast. It is used to examine breast tissues closely following the appearance of signs of cancer or a suspicious result in a screening mammogram. It can be used to pinpoint an abnormal area to be biopsied (surgically remove tissue) for further examination. It takes longer than a screening mammogram because there are more images of the breast, taken from different angles.
Breast Ultrasounds use high-frequency sound waves to develop images of the breast. It is commonly used in conjunction with mammogram to further examine breast lumps and other abnormalities, to determine if a lump is a tumour or a cyst and to find an abnormal area for a biopsy.
Magnetic Resonance Imaging (MRI) uses magnetic fields to create a three-dimensional image of the breast. MRI’s are not regularly used to diagnose breast cancer, however, they are often used to investigate breast cancer tissues when results from other imaging tests are unclear. They are also often combined with mammography to help detect hereditary breast cancers.
It is important to note that having dense breasts (made up of less fatty tissue and more glandular and fibrous tissue) can make it more difficult for mammograms to detect breast cancer. Dense breasts are more common amongst younger women, as breast tissue becomes less dense with age. Consult your healthcare provider if you have questions about breast density.
In a biopsy, cells or tissue from a suspicious area of the breast are removed and studied under a microscope to determine if cancer is present. There are many different biopsy methods, but the two most commonly used methods for breast cancer are:
Your health care provider can discuss with you which type of biopsy is best for your case.