Over the last 40 years, huge advances have been made in breast cancer screening technology, training, and quality standards to improve the equipment, techniques, staff knowledge and expertise, and image interpretation by radiologists.
Screen-film mammography remains the most commonly used method of breast cancer screening in many places. It has been widely tested and proven to help reduce deaths from breast cancer by 25-35 per cent in women who start screening by mammography from the age of 40.
Digital mammography is gradually replacing screen-film mammography in Canada. This is because it is better at detecting breast cancer in women in their 40s, women 50+ who have not gone through menopause, and women with clinically diagnosed dense breasts. Wherever it is available, the Canadian Breast Cancer Foundation encourages women to be screened with digital mammography.
For women who are at average risk of breast cancer (approximately 80 per cent of Canadian women), mammography is the most effective and appropriate screening method. In the section below, we introduce other technologies that are used alongside digital mammography to screen women at higher risk of breast cancer – as well as newer screening technologies that are being developed.
Breast ultrasound is useful as an additional screening technology in women at higher risk of developing breast cancer or women with clinically diagnosed dense breasts. Where breast MRI is not available, ultrasound has a role to play in screening women at intermediate or high risk of breast cancer. Breast ultrasound is often used in combination with mammography and MRI to provide additional screening information and is also a method used for breast cancer diagnosis.
The value of Breast Magnetic Resonance Imaging (MRI) is as a screening tool for women who are at high risk of breast cancer, combined with digital mammography.
Newer screening technologies
Molecular breast imaging is being tested for its ability to detect smaller, earlier breast cancers in high-risk women with clinically diagnosed dense breasts. It will not replace mammography, but may offer a more effective screening option for some. A clinical trial of this new technology is taking place in Canada, but the technology is not licensed for population-based breast cancer screening here.
Other technologies are being developed that may help to improve the earlier detection of breast cancer in the future. They include: digital breast tomosynthesis, breast computed tomography, and biomarker imaging.
Thermography is not recommended for breast cancer screening
Research has shown that thermography is not an effective way of detecting breast cancer. No credible research study has shown that thermography is an effective screening tool for detecting breast cancer earlier or as an indicator of a person’s risk of developing breast cancer.
While thermography has been available for many years, it is not recommended by any leading cancer organization or medical authority as a substitute for screening mammograms. Thermography is not licensed as a population-based breast cancer screening tool in Canada.
More Information:
Breast cancer screening by mammography
Genetic counselling and testing
About breast cancer
Methods used to diagnose breast cancer
Sources:
Canadian Breast Cancer Foundation. (2010). Earlier Detection and Diagnosis of Breast Cancer: A Report from It’s About Time! A Consensus Conference. Toronto, ON: Canadian Breast Cancer Foundation.
Canadian Breast Cancer Foundation. (2010). Earlier Detection and Diagnosis of Breast Cancer. Recommendations and Scientific Review from It’s About Time! A Consensus Conference. Toronto, ON: Canadian Breast Cancer Foundation.
Health Canada. It’s Your Health: Mammography. Accessed July 31, 2011.
Health Imaging. NJEM: Screening mammography recommended for most women. Accessed September 23, 2011.
Pisano, E. et al. Diagnostic Performance of Digital versus Film Mammography for Breast-Cancer Screening. In New England Journal of Medicine, 2005, vol. 353 (pp. 1773-83). Accessed September 23, 2011.
Society of Breast Imaging. Breast thermography. SBI position statement. Accessed July 31, 2011.
Warner, E. Breast-Cancer Screening. In New England Journal of Medicine, 2011, vol. 365 (pp. 1025-1032). Accessed September 23, 2011. Subscription or payment is required to access the full article.