Cervical Screening Participation and Retention
Measure: Participation: percentage of Ontario screen-eligible women, age 21 to 69, who completed at least 1 Pap test in a 42-month period
As of this Report:
Approximately 2.75 million Ontario women age 21 to 69 (62% of eligible women) were screened for cervical cancer with a Pap test in the 42 month period of 2014 to 2016 (2014–2016). This represents a decrease of 4% from the 2005–2007 period, when 66% of eligible women were screened.
The number of women eligible for screening through the Ontario Cervical Screening Program (OCSP) (Ontario’s organized cervical screening program) has continued to increase, from 4 million women in 2005–2007 to 4.4 million women in 2014–2016.
In 2010, 80% of the women who had a normal Pap test result that year returned for a subsequent Pap test within 42 months. Sixty-two percent of Ontario women who had a normal Pap test result in 2013 returned for another Pap test within 42 months, which represents a decrease of 18%.
Cancer Care Ontario revised its cervical screening guidance in 2012. This included increasing the recommended screening interval from annually to once every 3 years. Changes to the Ontario Health Insurance Plan fee schedule were made as a result of the new recommendations. Women screened in 2011 and 2012 would be expected to be re-screened in 2014 and 2015, respectively, achieving a total of 1 screening test in the 42-month period following their 2011 or 2012 Pap test. This change in the OCSP-recommended screening interval may have contributed to the decrease in screening participation observed in recent years.
What is cervical 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 organized screening programs for 3 types of cancer: breast, cervical and colorectal.
Measure: Retention: percentage of Ontario screen-eligible women, age 21 to 66, who had a subsequent Pap test within 42 months of a normal Pap test result
As of this Report:
- The purpose of cervical screening is to prevent cervical cancer by identifying pre-cancerous changes in the cells of the cervix. In Ontario, the cervical screening test currently in use is the Pap test. Changes to cervical screening tests are under consideration.
- Cancer Care Ontario updated its cervical screening guidance in 2012. It now recommends cervical screening every 3 years for women age 21 to 69 who are, or who have ever been, sexually active. Women can stop screening at age 70 if they have had 3 or more normal tests within the previous 10 years .
- Changes in the cervix that lead to cancer are called precursor or pre-cancerous lesions, and they usually develop slowly over many years. Screening is the best way to find the early cell changes that might lead to cervical cancer because those early cell changes do not have any symptoms.
- Colposcopy is an exam done by a specially trained doctor (i.e., a colposcopist) after a woman has an abnormal screening test result. It is the next step in the investigation of most abnormal screening test results. The colposcopist may remove or take a biopsy of abnormal-looking tissues, make a diagnosis and (if necessary) develop a treatment plan. After the diagnostic process is complete, a woman with a precursor lesion requiring treatment may undergo a loop electrical excision procedure, laser therapy or cold knife cone biopsy . Treating precursor lesions can prevent cervical cancer from developing.
What do the results show?
Cervical screening participation decreased for the period of 2014–2016 (Figure 1).
- Provincial cervical screening participation for the period of 2014–2016 was 62%. This is lower than it was for 2005–2007 (66%), and it falls short of the 85% Ontario Cancer Plan target.
- Approximately 2.75 million Ontario women age 21 to 69 were screened for cervical cancer in 2014–2016. During the 2014-2016 period, the Local Health Integration Network (LHIN) with the highest cervical screening participation was North Simcoe Muskoka (66%), while the Toronto Central LHIN had the lowest participation (58%).
Cervical screening participation varies by age group (Figure 2).
- For the period of 2014–2016, participation in cervical screening was highest in women age 40 to 49 (66%) and lowest in women age 60 to 69 (55%). Compared to 2011–2013, participation in cervical screening decreased in all age groups in 2014–2016.
Cervical screening retention needs improvement (Figure 3 and 4).
- Approximately 440,000 women who had a normal Pap test in 2013 returned for a Pap test within 42 months (62% of eligible women).
- Eighty percent of women who had a normal Pap test result in 2010 returned for a subsequent Pap test within 42 months. Sixty-two percent of Ontario women who had a normal Pap test result in 2013 returned for another Pap test within 42 months, a decrease of 18 percentage points.
- The Erie St. Clair LHIN had the highest retention of women with a normal Pap test in 2013 (65%). The Central West LHIN had the lowest retention of women with a normal Pap test in 2013 (57%).
- Retention has decreased for each cohort of women since 2010 and across all LHINs.
- Among women who had a normal Pap test in 2013 and returned for a Pap test within 42 months, retention was highest in those age 50 to 59 (64%). It was lowest in those age 21 to 29 (60%). A similar pattern can be seen in previous years.
Why is this important to Ontarians?
Cervical screening has reduced cervical cancer incidence and mortality.
- Cervical cancer almost always can be prevented with regular screening and the right kind of follow-up tests and treatment after abnormal screening test results. Finding cervical cancer or cell changes that could become cervical cancer is important. When cell changes or cancer of the cervix are found early, treatment is almost always successful.
- Most cervical cancers are found in women who have never been screened or those who have been screened less often than recommended by current cervical screening guidance . Organized cervical screening significantly reduces cervical cancer incidence (i.e., new cancer cases) and mortality (i.e., deaths) [3–5]. Long-term reductions in cervical cancer incidence and mortality in Ontario are linked to regular screening with appropriate and timely follow-up.
- It is estimated that 748 Ontario women will be diagnosed with cervical cancer in 2018 . In 2017, roughly 150 women died of the disease . This low incidence and low mortality are a measure of the success of Ontario’s screening system, but they also reflect the need for improvement in prevention and early detection of this essentially preventable disease.
- Human papillomavirus (HPV) infections can cause abnormal cell changes in the cervix and abnormal screening test results. Only abnormal cell changes caused by cancer-causing types of HPV put a woman at risk of getting cervical cancer. While there are over 100 different types of HPV, cervical cancer is mainly caused by the 12 to 15 high risk types of HPV infections. When a high risk infection persists (does not go away) for a number of years, it can lead to cervical cancer.
- HPV is passed from one person to another through intimate (i.e.., skin-to-skin) sexual contact. HPV infections are common, and up to 80% of sexually active men and women will have an HPV infection in their lifetime [8, 9]. Most HPV infections commonly go away on their own without causing any harm, especially in women under age 30. Factors that determine the clearance of a high risk HPV infection (as opposed to its persistence) are not well understood.
- Because pre-cancerous cervical changes rarely cause symptoms, screening is the only way to find early cell changes that could lead to cervical cancer.
Cervical screening needs to continue despite HPV vaccination.
- Vaccines are now available to prevent the most common cancer-causing HPV infections . The HPV vaccine is most effective at preventing cervical cancer when administered before someone becomes sexually active. However, even women who receive the HPV vaccine still need to get cervical screening.
- The HPV vaccine does not protect against all cancer-causing HPV types, and it does not eliminate HPV infections acquired before a woman gets vaccinated. Only screening can protect against cervical cancer that is caused by an earlier infection.
How does Ontario compare with other jurisdictions?
- Ensuring that the data and measures from other jurisdictions are comparable to those in Ontario is a challenge. Caution should be used when comparing Ontario’s indicator results to those from other jurisdictions due to potential differences in data definitions, methodologies and time periods. Cross-jurisdictional comparison, however, is still useful for providing a rough indication of how well Ontario is doing compared to other jurisdictions.
- For the period of 2014–2016, Ontario’s cervical screening participation (Pap test completion) among eligible women was 62%, compared to 70% in Australia. However, Australia uses a different reporting period (24-month vs. 42-month in Ontario) .
- For more information on comparisons of cervical screening participation among jurisdictions, see the Cancer Screening Quality Index’s (CSQI’s) screening comparison section.
- Cancer Care Ontario’s current guidance recommends HPV testing as the screening test for cervical cancer. Cancer Care Ontario is working with the Ministry of Health and Long-Term Care to implement HPV testing in the OCSP.
- In the interim, the OCSP supports continuing to use the Pap test as the cervical screening test.
- Cancer Care Ontario is moving towards fully organized cervical screening to improve the effectiveness of the OCSP. Screening participation rates remain a priority for the OCSP.
- Cancer Care Ontario is working to improve cervical screening participation and retention in eligible women, and it is pursuing multiple strategies to engage populations where screening participation is low.
- The OCSP correspondence program, which supports cervical screening participation and retention, began in the fall of 2013. Eligible women are mailed letters inviting them to get screened for cervical cancer, advising them of their test results (I.e. abnormal versus normal) and reminding them when it is time to return for screening. In 2018, the OCSP will be implementing a new invitation letter format intended to increase cervical screening participation.
- Cancer Care Ontario has developed an online Primary Care Screening Activity Report (PCSAR) for all 3 screening programs (breast, cervical and colorectal cancer). This tool, which is 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 due for screening and follow-up.
- Cancer Care Ontario is developing evidence-informed strategies to increase access, align processes, improve practices and enhance the quality of colposcopy services in the province. The OCSP recently released evidence-informed clinical guidance for the delivery of colposcopy services in Ontario . Next steps include working with regional partners to encourage implementation of this guidance.