What is a mammography?
Mammography is the use of low-dose X-rays to take detailed images, known as mammograms, of breast tissue from different angles.
Two types of mammography are available, depending on the situation:
Screening mammography is performed to detect abnormalities before observable signs or symptoms appear:
- Following receipt of a letter as part of the Quebec Breast Cancer Screening Program (PQDCS).
- Following a medical prescription as part of a personalized screening strategy based on a person’s breast cancer risk level.
Screening mammography is performed on both breasts to detect masses or areas of abnormal breast tissue that cannot be perceived by touch. Most of the time, screening mammography can detect cancer early, in the very first stages of development of the disease, sometimes in the precancerous stage.
Diagnostic mammography may be prescribed by a physician after an abnormality is identified, most often following a visual or clinical breast exam or a screening mammography.
Diagnostic mammography is more in-depth and takes longer than a screening mammography. In this exam, further complementary mammograms are taken from different angles to more precisely examine a specific area of the breast. Even if an abnormality has been detected in only one breast, diagnostic mammography is usually performed on both breasts for comparison purposes.
For more information on mammography, we encourage you to read our blog post Mammography: Who, why and how?
What happens during a mammography?
The patient stands in front of the mammography machine. Each breast is placed between two plastic plates which are pressed together to flatten the breast. This makes it possible to obtain clearer images and to minimize the amount of radiation used. The patient must stay still while the mammograms are taken. This exam often lasts only a few minutes.
Reliability of a mammography
Mammography is the most recognized and reliable method for detecting breast cancer. However, no cancer screening test is foolproof, including mammography. For example, mammography may yield a false positive when it indicates the presence of a cancer that does not actually exist. Conversely, false negatives are also possible, when mammography fails to detect actual cancerous cells.
Pain and discomfort during a mammography
Mammography can be uncomfortable or even painful for some women due to the compression of the breasts during the test. However, this feeling lasts only a few seconds. Discomfort may be lessened by following the advice below in the How to prepare for a mammogram section.
Furthermore, if you are experiencing significant discomfort before the mammogram, don’t be shy to tell the person administering the X-ray so they can adjust the compression.
It is important to note that this compression cannot cause breast cancer, nor can it cause an existing tumour to grow more quickly or spread.
How to prepare for a mammography?
If your breasts tend to be sensitive, try to:
- undergo the mammography one week to 10 days after menstruation begins.
- avoid beverages and foods containing caffeine, such as some drinks or chocolate a few days prior to the mammography.
The day of the test:
- Wear a two-piece outfit so you can undress from the waist up.
- Do not apply deodorant, antiperspirant, cream, powder or perfume on the breasts and underarms prior to the exam.
- Avoid necklaces, pendant earrings and any other bulky jewelry.
How are the mammography results interpreted?
Radiologists look at the mammograms to see if they can identify any abnormal areas. They use the BI-RADS (Breast Imaging-Reporting and Data System) classification developed by the American College of Radiology to report the results of the mammography and the suggested next steps.
The BI-RADS classification is as follows:
- BIRADS 0: Incomplete, further mammograms needed
- BIRADS 1: Normal
- BIRADS 2: A benign (i.e., not serious) abnormal area identified that does not require further monitoring or testing
- BIRADS 3: An abnormal area identified that is probably benign for which short-term (three or six months) monitoring is advised
- BIRADS 4: An undetermined or concerning abnormal area identified
- BIRADS 5: An abnormal area suggestive of cancer identified
Based on the mammogram results, your physician will advise you either not to do anything, to monitor closely or to proceed with more in-depth tests like a breast ultrasound. When the mammograms are classified BI-RADS 4 or 5, physicians will request a biopsy. Biopsy is the only test that can definitively confirm a breast cancer diagnosis.
For more information on mammography, see our blog post Mammography: Who, why and how?
Mammography and breast implants
People with breast implants can undergo mammography, but it is important to inform the person performing the exam. Medical imaging technologists are trained to minimize compression with the machine to avoid rupturing the implant.
Mammography is only truly contraindicated after recent breast surgery (reconstruction, reduction, augmentation) or sternotomy (heart surgery).
To learn more about breast implants and breast cancer, see our blog post Breast implants and breast cancer: what you need to know.
Are you feeling anxious while waiting for or after receiving medical test results? You’re not alone. Call us free of charge and in full confidentiality from anywhere in Quebec, Monday to Friday, from 9 a.m. to 5 p.m. at 1 855 561-PINK (7465) or write to us at [email protected].
References
- Canadian Cancer Society
- Ministère de la santé et des services sociaux du Québec
- Institut national de santé publique du Québec
- American College of Radiology
- Ordre des technologues en imagerie médicale, en radio-oncologie et en électrophysiologie du Québec (OTIMROEPMQ)