Breast Cancer Screening Follow-up
In 2016, over 6,400 Ontario women age 50 to 74 who had an abnormal Ontario Breast Screening Program (OBSP) mammogram and needed tissue biopsy for a definitive diagnosis were diagnosed within the recommended 7 weeks of the abnormal result . This number represents an increase of 7 percentage points, from 73% in 2013 to 80% in 2016.
Measure: Follow-up: percentage of Ontario screen-eligible women, age 50 to 74, with an abnormal OBSP screening mammogram result who needed a tissue biopsy and were diagnosed (benign or with cancer) within 7 weeks of the abnormal screen date
As of this Report:
What is breast cancer screening?
- Cancer screening is testing for people who may be at risk of getting cancer, but who have no symptoms and generally feel fine. It is not meant to diagnose cancer. Instead, it helps determine which people are more likely to develop cancer in the future. Ontario operates screening programs for 3 types of cancer: breast, cervical and colorectal.
- The purpose of breast cancer screening is to find cancer at an early stage, when it may be smaller and easier to treat.
- A mammogram uses low-dose X-rays to produce images of the breast . A breast magnetic resonance imaging (MRI) scan uses radio waves and a magnetic field to create cross-sectional images of the breast and an intravenous contrast agent (e.g., dye) is used most of the time. Both tests can find breast cancers when they are small, less likely to have spread and more likely to be treated successfully.
- Breast cancer screening with mammography is recommended every 2 years for most women age 50 to 74 .
- Breast cancer screening with mammography and breast MRI (or screening breast ultrasound if MRI is not medically appropriate) is recommended every year for women age 30 to 69 who are identified as being at high risk for breast cancer .
- Most women with an abnormal mammogram result will not necessarily have breast cancer . More tests are needed after an abnormal mammogram result to determine whether cancer is present.
- Diagnostic assessment includes additional radiological or surgical procedures, such as diagnostic mammography, ultrasonography, and core or open surgical biopsy.
- In Ontario, breast cancer screening occurs through both OBSP (Ontario’s population-based breast cancer screening program) and non-OBSP sites. For a map of locations, see Breast cancer screening participation.
I believe screening is very important: my cancer was discovered during a routine screening test and this this early detection allowed me to get the required treatment quickly and effectively.
– Wendy D., Patient/Family Advisor
What do the results show?
Follow-up performance within the recommended interval is improving for women who need a tissue biopsy (i.e., the time between an abnormal screen and diagnosis) .
- In 2016, 80% of women who needed a tissue biopsy were diagnosed within 7 weeks of their abnormal mammogram result. Seven-week (with tissue biopsy) follow-up has improved annually since 2013 (when it was 73%), but it still falls below the national target of 90%.
- There was considerable regional variation for the 7-week (with tissue biopsy) follow-up indicator. The Local Health Integration Networks (LHINs) with the highest 7-week (with tissue biopsy) follow-up for 2016 were Erie St. Clair and South West, which each achieved the national target of 90%. The North West LHIN had the lowest 7-week (with tissue biopsy) follow-up (34%). In 2017, the North West LHIN began a series of initiatives to improve performance for this indicator.
- Most LHINs improved in 7-week (with tissue biopsy) follow-up performance from 2013 to 2016. From 2013 to 2016, the South East LHIN improved its 7-week (with tissue biopsy) follow-up performance by 18 percentage points, from 64% to 82%. Other LHINs also showed meaningful improvement in performance for this indicator, including Erie St. Clair (16 percentage point improvement) and South West (14 percentage point improvement).
Follow-up is consistent across age groups.
- Seven-week (with tissue biopsy) follow-up was similar across age groups in 2016. It was lowest in women age 50 to 54 (78%) and highest in women age 70 to 74 (82%). A similar pattern can be seen in previous years.
Why is this important to Ontarians?
Delay between an abnormal screening mammogram and diagnosis can be very stressful for women and may lead to poor outcomes.
- Psychological distress intensifies as the wait time for diagnosis gets longer .
- The OBSP offers multidisciplinary breast assessment (i.e., diagnostic) services through 70 breast assessment sites (Figure 1).
- Coordinated diagnostic procedures ensure that a diagnosis is made as effectively as possible. Coordinated diagnosis through OBSP assessment sites allows treatment to begin more quickly, potentially reducing participant anxiety and improving outcomes (e.g., reducing deaths and morbidity) .
- Diagnostic intervals are affected by factors such as human and other resource shortages, including access to imaging and surgical services. Cancer Care Ontario continues to work with relevant partners to find solutions for improving follow-up times.
Organized screening offers several important benefits to women and their healthcare providers.
- The OBSP and High Risk OBSP provide high-quality screening for most women through the use of mammography, and through mammography and MRIs for women at high risk (or screening breast ultrasound if MRI is not medically appropriate).
- Quality assurance is ensured through the accreditation of all OBSP sites by the Mammography Accreditation Program of the Canadian Association of Radiologists.
- Communication to women and healthcare providers includes the following:
- Women eligible for screening through the OBSP are sent invitations to get screened, along with information about breast cancer screening and details on how to find an OBSP site.
- After their screening appointment, women with normal screening results get letters telling them their results are normal.
- Women screened through the OBSP get letters reminding them when to get screened again.
- OBSP sites follow up on abnormal screening results and send normal and abnormal results to a woman’s healthcare provider.
- Coordination and navigation includes the following:
- High Risk OBSP sites arrange genetic assessment (if appropriate) for women referred to the program.
- High Risk OBSP sites book screening mammography and screening breast MRI (or screening breast ultrasound if MRI is not medically appropriate).
- The OBSP indicates whether a woman should be screened in 1 year or 2 years based on her screening results and risk factors.
- OBSP assessment sites help guide women with abnormal screening results to diagnosis by coordinating follow-up tests and documenting the results of those tests.
- Cancer Care Ontario will continue to monitor follow-up of abnormal results and work with regional partners to improve performance.
- The OBSP continues to expand, with new sites being brought into the program in 2017 and 2018.