Recent Changes in Cervical Cancer Screening in Canada

Transcription

1 Recent Changes in Cervical Cancer Screening in Canada Meg McLachlin, MD, FRCPC Program Head, Pathology Senior Medical Director, Diagnostic Services Recent Changes in Cervical Cancer Screening in Canada Status of Cervical Screening in Canada Potential impact of HPV vaccination Primary HPV testing and the implications for screening practices 3 1

2 Screening Participation Canadian Target Percentage of HSIL+ Pap Test Results with Histologic Confirmation of CIN 2+, Canadian Target Age standardized Invasive Cervical Cancer Incidence Rate Per 100,000 Women By Province, Ages 20+, Canadian Target by 2037 (Based on 70% vaccination and 80% screening) 2

3 Screening History For Women Diagnosed With Invasive Cervical Cancer By Histology, HPV Vaccination Status January 2013 Province or Territory Target population Percentage who received first dose British Columbia Grade 6 and 9 Grade % (2012) Grade % (2011) Alberta Grade % (3 doses, ) Saskatchewan Grade 6 73% (2009) Manitoba Grade 6 72% (2012) Ontario Grade 8 59% (3 doses) Quebec 9 10 years of age (grade 4) years of age (grade 9) Grade 4 84%(2009) Grade 9 91%(2009) New Brunswick Grade 7 Grade % (1 dose) Nova Scotia Grade 7 72% (3 doses, 2009) Prince Edward Island Grade 6 80% (estimate, 2009) Newfoundland and Labrador Grade 6, catch up in grade 9 Grade 6 92%(1 dose, 2009) Grade 9 84%(1 dose, 2009) 8 Prediction #1 Cervical cancer prevention vaccination and screening will have to be delivered in an increasingly organized fashion with ongoing monitoring and evaluation 3

4 Cervical Screening Recommendations Age to Start NL NS ON MN SK AB BC All SA 3 yr after SA or 21 (earlier) Interval X3 Q 2 yr Age to Stop Within 3 yr SA X3 Q 2 3 yr 3 years after SA Q 2yr Onset of SA X2 Q 3 yr March or within 3 yr SA (later) x3 Q 3 yr Onset of SA x3 Q 2 yr None 75 yr 70 >70 yr none >69 >69 yr SA sexually active Potential Harms of Screening Adolescents High rates of low-grade, mostly transient abnormalities 90% will clear infection within 2 years Unnecessary anxiety from detection and treatment Treatment linked to adverse future pregnancy outcomes No protective effect with screening Incidence rates, by age group, Cancer Care Ontario (Ontario Cancer Registry, 2010). 4

5 Cervical Screening Recommendations Fall 2014 NL NS ON MN SK AB BC Age to Start 20 + SA 21 or within 3yr SA (earlier) 21 or later 21 or later 21 or later 21 or later 21 or within 3yr SA (earlier) Interval Age to Stop X3 Q 3 yr X3 Q 2 yr Q 3yr Q 3yr Q 2yr X3 Q 3 yr x3 Q 3 yr x3 Q 2 yr > 69 yr > 70 yr > 70 yr > 70 yr > 69 yr > 69 yr > 69 yr SA sexually active Ontario GYN Cytology Volumes New guidelines introduced 39% drop in overall volume Data from Cytobase 5

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7 Impact of Human Papillomavirus Vaccination on Cervical Cytology Screening, Colposcopy, and Treatment Rodríguez et alo. Am J Epidem, 2013 STATS 101 Prevalence affects the predictive value of any test. This means that the same diagnostic test will give you different information according to the clinical setting in which you are applying it. Falling Prevalence Leads To False Positive Results Prediction #2 Decreasing HPV rates will lead to poorer performance in cytology screening. i.e. our jobs will get a lot harder 7

8 E Franco, National Symposium on Infectious Agents & Cancer Toronto, March 11, 2010 Efficacy of HPV-based screening for prevention of invasive cervical cancer: follow-up of four European randomised controlled trials Guglielmo Ronco, Joakim Dillner, K Miriam Elfström, Sara Tunesi, Peter J F Snijders, Marc Arbyn, Henry Kitchener, Nereo Segnan, Clare Gilham, Paolo Giorgi-Rossi, Johannes Berkhof, Julian Peto, Chris J L M Meijer, and the International HPV screening working group Main Findings: HPV-based screening provides 60-70% greater protection against invasive cervical carcinomas compared with cytology. Data of large-scale randomised trials support initiation of HPV-based screening from age 30 years and extension of screening intervals to at least 5 years. 8

9 Cervical Screening with Primary HPV testing Negative Repeat HPV DNA at X year intervals Negative Cervical Sample (Pap) High risk HPV DNA testing Negative Repeat hrhpv testing Positive Cytology Positive Colposcopy Questions Which test? When to start? Interval? Triage? Risk reduction? Positive Following a comprehensive review of the current evidence for cervical screening, MSAC has recommended for both HPV vaccinated and unvaccinated women that: An HPV test every 5 years is more effective than, and just as safe as, screening with a Pap test every 2 years. An HPV test every 5 years can save more lives and women would need fewer tests than in the current 2 yearly Pap test program. Laboratory Impacts Technology - evolving Throughput / volumes Costs program funding vs user pay Quality assurance Standardized operating procedures Standardized, integrated reporting Human resources Competencies and training 9

10 Cervical Cancer Screening Expert Meeting Moving Forward in a Vaccinated Population March 20, 2014, Toronto, ON Purpose: discuss and formulate options for optimal cervical cancer screening in era of HPV vaccination > For the immediate short term, continue with current screening protocols regardless of vaccination status. However, detailed planning for an eventual move to primary HPV screening should begin immediately. 10

11 Implementing HPV Testing: Anticipating the Challenges What should we be working NOW? To achieve implementation of primary HPV testing for cervical cancer screening in Canada, the provinces will have to develop business cases Liquid based cytology should be implemented for those programs currently using conventional cytology Education for both the public and practitioners on the link between HPV and cervical cancer is essential Report of the November 2014 PCCSN Workshop Prediction #3 Cervical cancer screening will shift to primary HPV testing +/- cytology triage. The laboratory community needs to start preparing for this change. 11

12 With my thanks to Kathleen Decker, Chair Monitoring Program Performance, PCCSN Joan Murphy, Ontario Cervical Screening Program Karen Canfell, University of New South Wales Australia Gina Ogilvie, Medical Director, Clinical Prevention Services, BC Centre for Disease Control Recent Changes in Cervical Cancer Screening in Canada Meg McLachlin, MD, FRCPC Program Head, Pathology Senior Medical Director, Diagnostic Services 12