printemailclick to share buttonfacebooktwitterlinkedin
New study highlights effectiveness of Ontario’s High Risk Breast Cancer Screening Program
Results published by the Journal of Clinical Oncology
Posted on 2014/06/16

Cancer Care Ontario (CCO) is leading the way in care for women who are at high risk for developing breast cancer, as shown in a new study published in the Journal of Clinical Oncology.

The study titled “Effectiveness of screening with annual magnetic resonance imaging and mammography: results of the initial screen from the Ontario High Risk Breast Screening Program,” was authored by CCO Senior Scientist Dr. Anna Chiarelli.  It evaluated the first year of the high risk breast screening program, which launched in 2011 as an expansion of the Ontario Breast Screening Program (OBSP).

The results of the study show that the program’s cancer detection rate was 16.3 per 1,000, which is three times that for average risk women (about five per 1,000). 

These findings are evidence that high risk screening can be effectively implemented into an organized breast screening program to provide women with all the benefits of organized screening, such as reminding participants of their next screening visit, notifying participants of results, navigating participants through the screening process, and the reassurance that comes from participation in a program supported by a quality assurance framework.  

Women between the ages of 30 and 69 who are eligible for the OBSP High Risk Screening Program are screened using annual breast magnetic resonance imaging (MRI) combined with mammography.  Women who are at average risk for breast cancer between the ages of 50 and 74 are generally screened using mammography every two years.

Quick Facts

  • Of the 35 breast cancers detected during the first year of the OBSP High Risk Screening Program, all were detected by MRI, either alone or with mammography.
  • Most of the breast cancers were invasive and were detected among women who were known gene mutation carriers.  
  • Approximately 34,000 women (aged 30 to 69 years) in Ontario are at high risk for breast cancer. This represents approximately one per cent of the population.
  • Screening tests may miss some breast cancers. Also, some cancers develop in the time between screens. These are among the reasons that regular screening is important.


“The results of this study are very encouraging and prove that using annual breast MRI combined with mammography is benefitting women who are at high risk for breast cancer.  The findings of this study can now be used by other organizations that are developing programs of their own.”
- Dr. Anna Chiarelli, Senior Scientist, Cancer Care Ontario

“This study shows that the program we designed is working as planned and is helping detect breast cancer in the high risk population.  I would encourage women who feel they might be at high risk for breast cancer to speak with their doctor as there are screening options available for them.”
- Dr. Derek Muradali, Radiologist In Chief, Ontario Breast Screening Program

“The OBSP High Risk Screening Program has strengthened relationships between genetics clinics and OBSP screening sites. The program has also introduced a navigation service to ensure that women who think they may be at high risk for breast cancer receive the risk assessment and screening services they need.”
- Dr. Andrea Eisen, Ontario Breast Cancer Lead, Cancer Care Ontario

Cancer Care Ontario – an Ontario government agency – drives quality and continuous improvement in disease prevention and screening, the delivery of care and the patient experience, for cancer, chronic kidney disease and access to care for key health services. Known for its innovation and results-driven approaches, Cancer Care Ontario leads multi-year system planning, contracts for services with hospitals and providers, develops and deploys information systems, establishes guidelines and standards and tracks performance targets to ensure system-wide improvements in cancer, chronic kidney disease and access to care.

Media contact:
Tori Gass
Phone: 1-855-460-2646

Last modified: Mon, Jun 16, 2014
cancer care ontario | action cancer ontario   620 University Avenue Toronto Ontario, Canada M5G 2L7   Phone: 416.971.9800 Fax: 416.971.6888

Please help improve the quality of our website by answering 10 brief questions in our online survey. Would you like to participate?