Breast Cancer Screening Follow-Up

Measure	Desired Direction	As of this Report
Percentage of Ontario screen-eligible women aged 50 to 74, with an abnormal OBSP screening mammogram result who were diagnosed (benign or with cancer) within the recommended time interval: within 5 weeks of the abnormal screen date, if no tissue (core or surgical) biopsy
Percentage of Ontario screen-eligible women aged 50 to 74, with an abnormal OBSP screening mammogram result who were diagnosed (benign or with cancer) within the recommended time interval: within 7 weeks of the abnormal screen date, if with a tissue (core or surgical) biopsy
See Methodology and Approach to find out how the ratings are calculated.

Key findings

In 2015, 94% of screen-eligible women in Ontario aged 50 to 74 who had an abnormal Ontario Breast Screening Program (OBSP) mammogram and did not need tissue biopsy for a definitive diagnosis were diagnosed within the recommended 5 weeks of the abnormal result¹. This represented approximately 40,600 women and an improvement of 8 percentage points compared to 2011 (86%).  Also in 2015, approximately 6,200 Ontario women aged 50 to 74 who had an abnormal OBSP mammogram and needed tissue biopsy for a definitive diagnosis were diagnosed within the recommended 7 weeks of the abnormal result¹. This represented an increase of 9 percentage points, from 70% in 2012 to 79% in 2015.

Also in 2015, approximately 6,200 Ontario women aged 50 to 74 who had an abnormal OBSP mammogram and needed tissue biopsy for a definitive diagnosis were diagnosed within the recommended 7 weeks of the abnormal result¹. This represented an increase of 9 percentage points, from 70% in 2012 to 79% in 2015.

What is breast cancer screening?

• A screening test identifies people in a healthy, asymptomatic population who may be at risk for disease. It is not a diagnostic test. The purpose of breast screening is to find cancer at an early stage, when it is easier to treat. Ontario operates screening programs for 3 types of cancer: breast, cervical and colorectal.
• A mammogram uses low-dose X-rays to produce images of the breast². A breast magnetic resonance imaging (MRI) scan uses magnetic waves and an intravenous contrast agent (e.g. dye) to create cross-sectional images of the breast². Both tests can show changes in the breasts that may be early signs of breast cancer, even when the changes are too small for a woman or her doctor to feel or see.
• Breast cancer screening with mammography is recommended every 2 years for average-risk women aged 50 to 74².

In my words 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

• Breast cancer screening with mammography and breast MRI is recommended every year for women aged 30 to 69 who are identified as being at high risk for breast cancer³.
• Most women with an abnormal mammogram result will not have breast cancer². 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 and/or open surgical biopsy.
• In Ontario, breast cancer screening occurs through the OBSP (an organized province-wide screening program) and through non-OBSP sites. For a map of locations, see Breast Cancer Screening Participation.

What do the results show? 

Follow-up performance within the recommended intervals (i.e. the time between an abnormal screen and diagnosis) is improving¹, but it remains better for women who do not need a tissue biopsy (Figures 2 and 4).

• In 2015, 94% of women who did not need a tissue biopsy were diagnosed within 5 weeks of their abnormal mammogram result. Five-week (without tissue biopsy) follow-up has improved annually since 2012 (when it was 91%), and it has surpassed the national target of 90%.
• In the same year (2015), 79% 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 2012 (when it was 70%), but it still falls below the national target of 90%.
• The Local Health Integration Networks (LHINs) with the highest 5-week (without tissue biopsy) follow-up for 2015 were Erie St. Clair, Central and Central East (96% for all).
• The North West LHIN had the lowest 5-week (without tissue biopsy) follow-up in 2015, at 86%.
• There was considerable regional variation for the 7-week (with tissue biopsy) follow-up indicator. The LHIN with the highest 7-week (with tissue biopsy) follow-up for 2015 was Erie St. Clair (86%). The North West LHIN had the lowest 7-week (with tissue biopsy) follow-up, at 57%.
• Most LHINs improved both 5- and 7-week follow-up performance measures from 2012 to 2015:
  • From 2012 to 2015, the South West LHIN improved its 5-week (without tissue biopsy) follow-up performance by 14 percentage points, increasing from 79% to 93%.
  • From 2012 to 2015, the North East LHIN improved its 7-week (with tissue biopsy) follow-up performance by 23 percentage points, increasing from 61% to 84%. Other LHINs also showed meaningful improvement in performance for this indicator, including South West (17 percentage point improvement), Erie St. Clair (15 percentage point improvement) and Central East (11 percentage point improvement).

Follow-up is consistent across age groups (Figures 3 and 5).

• In 2015, 5-week (without tissue biopsy) follow-up (Figure 3) was consistent across age groups. A similar pattern can be seen in previous years.
• Seven-week (with tissue biopsy) follow-up was also similar across age groups in 2015. Seven-week follow-up was lowest in women aged 50 to 54 (78%) and highest in women aged 70 to 74 (81%). 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 longer⁴.
• 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 quickly as possible. A quick diagnosis helps reduce anxiety for participants and allows treatment to begin more quickly, potentially 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 important advantages for women and physicians.

• The OBSP provides high-quality screening for women at average risk of developing breast cancer using mammography, and for women at high risk through mammography, plus magnetic resonance imaging (MRI) or ultrasound.
• Communication to women and health care providers includes:
  • women eligible for screening through the OBSP are sent invitations to get screened, along with information about breast cancer screening and how to find an OBSP site;
  • normal result letters are sent to women after their screening visits;
  • women screened through the OBSP are sent recall and reminder letters when they are due for their next round of screening; and
  • OBSP sites follow up on abnormal screening results and communicate both normal and abnormal results to a woman’s health care provider.
• Coordination and navigation includes:
  • arranging genetic assessment (if appropriate) for women who have been referred to the High-Risk OBSP;
  • booking mammography and breast MRI (or, if appropriate, screening ultrasound) appointments via OBSP sites;
  • suggesting an appropriate screening recall interval based on a woman’s screening result and risk factors; and
  • having OBSP assessment sites coordinate follow-up tests, track test results and provide navigation from abnormal screen to final diagnosis for women with abnormal screening results.

Next steps

• Cancer Care Ontario has developed an online Screening Activity Report (SAR) for all 3 screening programs (cervical, breast and colorectal cancer). This tool (accessed online) allows physicians in a patient enrolment model practice to see the complete screening status of each of their enrolled age-eligible patients, including those who are due for screening and follow up. Next steps include working with the Regional Primary Care Leads to identify barriers to adoption of the tool, and to promote and encourage use of the PC SAR.
• The OBSP continues to expand, with new sites being brought into the program in 2016 and 2017.

View Notes

1. Canadian Partnership Against Cancer. Report from the evaluation indicators working group: guidelines for monitoring breast cancer screening program performance. 3rd Edition. Toronto: Canadian Partnership Against Cancer; 2013.
2. Cancer Care Ontario. Ontario Cancer Screening Performance Report 2016. Toronto: Cancer Care Ontario; 2016.
3. Chiarelli AM, Prummel MV, Muradali D, Majpruz V, Horgan M, Carroll JC, et al. Effectiveness of screening with annual magnetic resonance imaging and mammography: results of the initial screening from Ontario high risk breast screening. J Clin Oncol. 2014 Jul 20; 32(21):2224–30.
4. Risberg T, Sorbye SW, Norum J, Wist EA. Diagnostic delay causes more psychological distress in female than in male cancer patients. Anticancer Res. 1996 Mar–Apr; 16(2):995–99.