Guest blog post by: Dr Simon Leeson (NHS Wales)
On Monday 17th September, Wales will become the first nation in the UK to fully convert its cervical screening programme from cytology-based screening to high risk human papilloma virus (hrHPV)-based screening. Our small country has a population of 3.17 million and Cervical Screening Wales invites around 236,000 women per year for cervical screening. The new programme will offer hrHPV testing with the Aptima mRNA test every 3 years from 25 years and every 5 years from 50 to 64 years of age. This follows an ‘early adopter’ phase which started in April 2017 involving 20% of the total screened population. This preliminary phase showed hrHPV-based screening to be effective with a test positive rate and referral rate to colposcopy following an abnormal cytology triage for hrHPV test positive cases consistent with that seen in other countries.
There are vast implications for Cervical Screening Wales. Laboratories will be rationalised from 4 down to 1 and we will transport all samples to Llantrisant, near Cardiff for hrHPV testing. The hrHPV positive tests will have cytology screening in Llantrisant and those samples with abnormal cytology will be sent to regional labs for local pathologists or Consultant Biomedical Scientists to report. Messenger RNA testing was considered the ideal platform having a high sensitivity for CIN2+ but also having a greater specificity than HPV- DNA tests. EQA schedules for HPV tests have needed re-evaluation as there are no second tests available from the sample as it is discarded unless a slide was made. Algorithms for the labs, administration departments and for colposcopists have had to be re-designed, particularly for the management of low-grade abnormalities.
Cervical Screening Wales has had a programme of training for all staff including the programme managers, sample takers and colposcopists for the management of abnormal results, but also to educate sample takers regarding what women need to know about HPV infection and what a positive hrHPV test means. Also, we have been continuously updating our stakeholders on progress via our newsletter and we have a communications strategy planned involving using social media alongside traditional routes. We have had public involvement in developing a new cervical screening booklet, and also new invitation and result letters.
An 80% increase in referral to colposcopy is anticipated in year 2 when persistently hrHPV positive, cytologically negative women are scheduled to be referred to colposcopy and is anticipated to represent just under 3% of each screening round. In the longer term referrals to colposcopy are expected to decrease. The proportion of CIN2+ is expected to decline within the referred population to colposcopy and adjunct technologies to improve detection of these lesions need to be considered for colposcopy clinics.
An all-Wales stakeholder day is planned to discuss the key programme challenges with all groups of staff from the Welsh cervical screening programme on 5th September 2018 in Newport.
Wales has a good compliance with HPV vaccination. Once vaccinated women (who were vaccinated at 12-13 years of age) enter the screening programme in 2020, screening intervals will need to be reviewed including considering reducing the number of screens recommended for the vaccinated population, dependent on decisions made by the UK National Screening Committee. The future is almost here and it looks exciting.
Click here for an update from the Welsh government
You may also be interested in this related content: Evidence that HPV vaccination works and evidence that HPV testing really works
The views expressed are those of the author. Posting of the blog does not signify that the Cancer Prevention Group endorse those views or opinions.
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