Prof Woo Yin Ling discusses her study on cervical cancer screening and self-sampling in pregnant women in Malaysia for cervical cancer elimination

Interview transcript:

Introduction

I’m Woo Yin Ling, a Professor of Obstetrics and Gynaecology at University of Malaya and a consultant gynaecological oncologist at University Malaya Medical Centre. My daily work involves caring for women with gynaecological cancers and so working towards cervical cancer elimination with equity in mind is of great interest to me.  This was the basis of innovating Program ROSE where I am now a founding trustee for ROSE Foundation.

What is the objective of your recent study on screening pregnant women for cervical cancer using HPV DNA testing? What are the key outcomes?

As we are all aware, the burden of cervical cancer is predominantly in the Lower Middle Income Countries (LMICs) where healthcare is stretched and infrastructure for organized screening is often non-existent; there isn’t even a formal system of call and recall when it comes to screening.

We know that to reach the 2030 targets for cervical cancer elimination, 70% of eligible women will require at least 2 HPV testing in their lifetime. This then begs the question: ‘What do we even do to reach these women?’ ‘How do we get to them?’

For the majority of women, they only see a doctor when they are unwell. Preventive screening is not a norm for them.

So where are the touchpoints between a woman of reproductive age and a healthcare professional (HCP)? The most obvious would be when she accesses antenatal care. In fact, the World Health Organisation (WHO) has recently updated its recommendations from a minimum of 4 antenatal care contacts to a minimum of 8 to improve women’s experience of care.

To me, this means that we have at least 4-8 opportunities to educate and screen a woman.  And we know how much time women wait in turn in the clinics before they see a doctor at such clinics. This provides us with ample opportunity to offer them self-sampling for HPV testing.

This was the basis of our study. The primary aim of the study was to ascertain the acceptability and performance of self-sampling in an antenatal population.

We approached approximately 2200 women, above 15 weeks gestation for this study, where 1600, which is 70% of them, agreed to participate. What does this suggest to you? It means that if you offered screening to this population, 70% of pregnant women would accept the invitation.

In this urban group attending a tertiary teaching hospital, 50% had never been screened before. 2/3 were between 28-40 weeks pregnant, meaning that they had a significant bump. Except for seven women out of this 1600, everyone opted for self-sampling. That is a whopping 99.6%! Of those who attempted self-sampling, only 24 abandoned the procedure. This is less than 2% and they asked for help from a HCP.

Overall, 98.8% of women who took part in the study expressed a preference for self-sampling.

So how did they fair? In terms of the performance, 1571 women, which is 95.7% of women, had a valid test result; with 68 women, which is 4.3%, having an invalid result.  The invalid rates in the general population is around 2%.

15 women, which is 0.9%, had blood stained swabs after sampling with no further complication. They had an uneventful pregnancy. There were no other adverse outcomes reported!

In this cohort, the HPV positive rate was 6.3%, which is similar to the Malaysian general population.

How may countries think about using this information for screening?

We now have information to show that it is safe to swab a woman for HPV testing from 15 weeks up to term. The idea of swabbing during pregnancy is not a new one. For example, in many countries, women are swabbed by HCPs for Group B Streptococcus as a predictor for preterm labour. So I do think this will allow opportunities for doctors to speak to women to screen and perhaps integrate cervical screening into the antenatal population.

How has this study influenced your overall clinical workflow?

This was a piece of meaningful research which has led to us expand it further.

We are now in the midst preparing a cross-over study to evaluate if women prefer self-sampling or a HCP sampling in pregnancy.

What we know from this study that more than 50% of women will accept HPV testing when offered during antenatal visits. Among them, more than 90% are willing to perform their own self-sampling.

The prevalence in the pregnant population is similar to the general population in Malaysia.

Based on your study findings, what recommendations do you have for improving cervical cancer screening in Malaysia and other Asia Pacific countries?

We have previously demonstrated the acceptability of self-sampling among Malaysian women. In fact, this is now offered to women as part of our national screening program.

This study confirms the acceptability and safety of self-sampling for HPV testing even among pregnant women.  In our study, the HPV DNA detection rate in pregnancy was not higher in the general population. It is evident that self-sampling allows for scalability and to reach more women during their reproductive age.  So here we have an acceptable tool to screen women when they encounter a HCP during their pregnancy.

As with all screening programs, you do need to think about follow up of those with abnormal screening results. In this study, among the antenatal population, the follow up of women was marginally lower at 70%. This is totally understandable as the responsibilities towards a newborn is great.  This needs to be factored in when thinking about introducing an antenatal program.

My recommendation has always been to have a systematic approach to cervical screening, ensuring that as many women have access to screening and treatment. Most importantly, you need to be able to follow up women who have a positive screen.  This study is a ‘technical study’ in that it shows that we can screen women during pregnancy.

But as countries transition to HPV testing, a screening registry to monitor population outcomes becomes very critical.

The views and opinions expressed by Prof. Woo Yin Ling are her own views and opinions. Roche disclaims all liability in relation to these views and opinions.