What is HPV?
The Human Papilloma Virus (HPV) is the name for a group of viruses that affect the skin and moist membranes of your body (including the cervix, anus, mouth and throat) and is responsible for almost all cases of cervical cancer.
What is the current screening programme for cervical cancer in the UK?
In 2016, the NHS announced its plans to change the screening procedure for cervical cancer and the change-over is currently being implemented across the UK. Previously, women were (and some still are) screened using a ‘smear’ test (called cytology), which involves checking for abnormalities in the cells on the cervix. However, in the new screening programme, all women will first be screened for the HPV virus (called HPV primary screening). If high-risk HPV is found, the sample will be further investigated for any abnormal cell changes. If HPV is not found, the sample will not need further investigation. This new screening programme will therefore help to identify women who are more at risk of developing cell changes or cervical cancer, which means we have a better chance at finding abnormal changes earlier. The HPV test is also more accurate than the cytology test – the HPV test is estimated to be between 90% and 95% reliable, whereas the cytology test is between 70% to 80% reliable.
What is HPV self-sampling?
Many women fail to attend their cervical screening tests for reasons, such as embarrassment, fear, or cultural or practical reasons (e.g. not being able to get time off work or travel to the clinic). As a solution, HPV self-sampling tests could be offered to non-attenders. A HPV self-sampling test would enable a woman to carry out the screening test herself, at a time convenient for her, in the comfort of her own home.
(Incidentally, for those who are interested, it is possible to order a HPV self test kit online via Superdrug for £48: https://onlinedoctor.superdrug.com/hpv-test.html ).
Where does the UK currently stand on HPV self-sampling?
In early December 2018, Professor Anne Mackie, who is the director of screening at Public Health England, confirmed that HPV self-sampling is currently under consultation by the UK National Screening Committee (UK NSC), the body that advises ministers and the NHS about screening and implementation of screening programmes. More specifically, they are considering the benefits of posting HPV self-sample kits to women who do not respond to invitations to attend screening at a clinic.
This coincided with the recent publication of a study by researchers from Australia and the US in the reputable British Medical Journal (BMJ) (Arbyn, Smith, Temin, Sultana & Castle, 2018). The study systematically reviewed and combined the findings from 81 studies: 56 studies examined the accuracy of a self-sampled HPV test conducted by women themselves versus a sample collected by a clinician, and 25 studies examined the response of women (who were irregularly or never screened) who were invited to self-sample for HPV versus those who were reminded to undergo the screening test conducted by a clinician.
The findings showed that:
1. Self-sampled tests were of approximately similar accuracy to the samples conducted by clinicians (around 10% less effective with a higher rate of false positives, meaning some women might be incorrectly told they have a positive HPV test).
2. Women who were posted self-sample kits to their homes were around twice as likely to provide a sample for testing compared to those who were reminded to attend a clinic for a regular test.
3. Offers of self-sampling to women in under-screened communities generated high participation rates (>75%).
4. However, there was high variability of response rates among different settings.
From these findings, authors concluded that, ‘Offering self-sampling kits generally is more effective in reaching under-screened women than sending invitations’. However, due to the slightly lower accuracy of the HPV self-sample test and higher rate of false positive results, the authors suggested that the home tests could be used as an alternative option for those women who do not feel comfortable or are not able to visit the doctor, but not replace the regular testing at clinics. Additionally, since the response rates among settings were highly variable, the authors suggested that pilot studies of self-sampling should be conducted before regional or national roll out of a self-sample kit for non-attenders.
Australia… always one step ahead!
It is reassuring to know that HPV self-sampling has already been incorporated into an existing cervical screening programme, and it comes as no surprise that this is in Australia! The renewed National Cervical Screening Program enables eligible women to conduct a HPV self-sample – women have to be at least 30 years of age and considered under-screened (defined as four or more years since their last smear test), or who have never been screened and who decline a clinician-collected sample. This decision followed the positive findings of a self-sampling pilot project conducted in Victoria. The pilot program demonstrated high acceptability of self-sampling among under-screened women from Aboriginal and Torres Strait Islander, culturally and linguistically diverse and disadvantaged backgrounds, with 86% of women who refused a practitioner-collected sample accepting the invitation to self-sample.
I am hopeful that the UK will eventually follow the footsteps of those Down Under; however I hope this is sooner rather than later (not five years later, as in the case of the HPV vaccination programme!)!
[All views and opinions are my own].
Arbyn, M., Smith, S. B., Temin, S., Sultana, F., & Castle, P. (2018). Detecting cervical precancer and reaching underscreened women by using HPV testing on self samples: updated meta-analyses. BMJ, 363, k4823.