The number of cervical screening appointments cancelled or unattended in the UK during the pandemic is staggering. The Eve Appeal and Jo’s Cancer Trust have done a great job raising awareness of the importance of screening and trying to help address the underlying causes during the recent cervical cancer prevention week.
This reduction in screening is setting us up for a tragedy that can be avoided. Providing alternatives to universal clinic-based screening is urgent; rolling out self-sampling could be an answer. Australia and Denmark already offer self-testing with very encouraging results, and trials are underway in the UK.
Self-collection would reduce the need to visit a medical facility for a specimen to be collected, although any positive results would require follow up.
A screening appointment may not seem like a priority because cervical abnormalities in the precancerous stages generally do not show symptoms, so there may not be an obvious cause for concern. These early precancerous changes are 95% curable with one simple treatment. However if these are not identified in a screening, over 10 years they will develop into cancer in around 30% of women.
Home-testing kits can easily be done by individuals; it involves inserting a small swab stick into the vagina. Then there are two options: the stick with the sample can be placed into a small test tube and sent to a lab for testing. Alternatively the stick can be rubbed onto a piece of card and sent to a lab. The card is then put into a computer that analyses the smear and performs the latest molecular tests. A urine sample (first void) can also be used to detect HPV.
Self-application tests can detect HPV and associated abnormal cytology and have been shown to have a high level of efficacy in detecting the premalignant stages of cervical cancer. Indeed, in many studies (see references below) the specimen collected by the home-testing method is comparable in terms of accuracy to those that have been collected by the physician. The testing for HPV as performed on these samples is most important in terms of management because if the HPV test is negative, the chance of having an abnormality is about 1%.
The great advantage of home sample collection – be it from a vaginal swab or from urine – is that it can detect not only HPV and abnormal cytology but also some of the new and exciting molecular diagnostic biomarkers like DNA methylation.
Screening is absolutely critical to reducing cervical cancer. The necessity for an alternative or supplement to in-person screening is clear; if this period could speed up the introduction of self-collection, that may be one of the very few positive long-term outcomes of the pandemic lockdowns.
Module 3b of the online Basic Colposcopy Course covers screening in detail.
Read more: Polman, NJ et al., Performance of HPV testing on self-collection versus clinician collected samples for detecting CIN2+: a randomized study, paired – screen positive, non-inferiority trial. Lancet Oncology (2019), Feb;20(2): 229-238
Gustavsson, I et al., Randomised study of HPV prevalence and detection of CIN2+ in vaginal self sample compared to cervical specimens collected by medical personnel, International Journal of Cancer (2020), 1;144(1): 89-97
Xu et al., Comparison of the performance of paired urine and cervical samples cervical cancer screening in screening populations, Journal of Medical Virology (2020), Volume 92, Issue 2, pages 234-240