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Human papillomavirus (HPV) infection, a common sexually transmitted disease, is associated with cancers of the cervix, vulva, vagina, penis, anus, and head and neck. Oropharyngeal squamous cell carcinoma (OPSCC; throat cancer) is a type of cancer involving the head and neck area that is rapidly increasing across the globe. There are higher rates of OPSCC among Indigenous populations relative to non–Indigenous Australian populations, although the HPV-attributable fraction remains unknown. For the first time at a global level, we plan to extend an Indigenous Australian adult cohort to monitor, screen, and ultimately prevent HPV-associated OPSCC and to undertake extensive cost-effectiveness modelling around HPV vaccination.
This study aims to (1) extend follow-up to a minimum of 7 years post recruitment to describe the prevalence, incidence, clearance, and persistence of oral HPV infection; and (2) conduct clinical examinations of the head and neck, oral cavity, and oropharynx and collect saliva samples for early-stage OPSCC testing.
We will continue to implement a longitudinal design for the next study phase, where we will ascertain the prevalence, incidence, clearance, and persistence of oral HPV infection at 48, 60, and 72 months; undertake clinical examinations/saliva assessments to detect early-stage OPSCC; and refer for treatment. The primary outcome measures are changes in oral HPV infection status, biomarker measures of early HPV-related cancer, and clinical evidence of early-stage OPSCC.
Participant 48-month follow-up will commence in January 2023. The first results are expected to be submitted for publication 1 year after 48-month follow-up begins.
Our findings have potential to change the way in which OPSCC among Australian Indigenous adults is managed, with desired impacts including cost-savings on expensive cancer treatments; improved nutritional, social, and emotional outcomes; and improved quality of life for both Indigenous adults and the Indigenous community more broadly. Continuing a large, representative Indigenous adult cohort to track oral HPV infection and monitor early OPSCC is essential to yield critical information to include in the management armamentarium of health and well-being recommendations for Australia’s First Nations.
PRR1-10.2196/44593
Human papillomaviruses (HPVs) are a heterogeneous group of circular, double-stranded DNA viruses that grow in stratified epithelium (skin and mucosa). Prior to the implementation of vaccination, HPV was the most common sexually transmitted infection in Australia, with an estimated 4 out of 5 Australians having an HPV infection at some point in their lives [
Oropharyngeal cancers include cancer of the middle part of the throat: the tonsils, soft palate, and the base of the tongue [
In 2008, age-standardized rates of lip, oral cavity, and oropharyngeal cancer in Australia were 11.0 per 100,000 for males and 4.1 per 100,000 for females [
There is little documented evidence of the incidence of OPSCC among Australian Indigenous persons. Indigenous persons living in Queensland were more likely than the total Queensland population to be diagnosed with head and neck cancers between 1997 and 2012, specifically in the base of the tongue/tonsil/oropharynx; the standardized incidence ratio was 2.16 (n=81) [
HPV 16-E6 antibodies are detectable in peripheral blood before diagnosis in the majority of HPV 16–driven OPSCCs. Using data from 743 incident OPSCC cases and 5814 controls from 9 population groups across Australia, North America, and Europe, Kreimer and colleagues [
Saliva covers the oropharyngeal mucosa and can be collected noninvasively, making it an ideal bodily fluid for early biomarker detection of HPV-induced OPSCC. Recent studies have examined HPV mitochondrial RNA (mRNA) in oral (oropharyngeal swab or saliva) samples from patients with head and/or neck squamous cell carcinoma. The high rates for HPV E6 oncoproteins and E6/E7 mRNA suggest that most patients were experiencing transcriptionally active HPV-related OPSCC [
The first phase of this prospective longitudinal cohort study was developed in partnership with Aboriginal communities in South Australia and funded by the National Health and Medical Research Council in 2016. The study is governed by an Aboriginal Reference Group, with data collected by trained Aboriginal research officers [
In continued partnership with Aboriginal South Australian stakeholders and study participants, the aims of the second phase of the Indigenous Australian HPV cohort study are as follows:
Aim 1: To extend follow-up to a minimum of 7 years post recruitment to describe the prevalence, incidence, clearance, and persistence of oral HPV infection, including high-risk types, across 48-, 60-, and 72-month follow-ups and to correlate with lifestyle and sociodemographic characteristics
Aim 2: To conduct a thorough clinical examination of the head and neck, oral cavity, and oropharynx and to collect anthropometrics and saliva samples for OPSCC testing
We will continue to implement a longitudinal design for the next study phase. A study schema is included in
Timing of data and sample collection. T: time point.
All participants initially recruited will be eligible for the 48-, 60-, and 72-month follow-ups. Retention strategies will involve those successfully used thus far: (1) continuing to employ Aboriginal staff who have built up personal relationships with participants and who are committed to following up participants despite challenges in doing so; (2) ensuring participants are contacted regularly to ensure the accuracy of contact details; (3) ascertaining contact details of 3 new key personnel who may know the whereabouts of participants should the study team be unable to contact them; (4) sending birthday and Christmas cards to participants; and (5) facilitating one-on-one relationships between study staff and participants, with study staff ideally seeing each of their participants for each research phase. We perceive no difficulties in continuing with the high retention of participants given our past success.
Ethics approval has been received by the Aboriginal Health Council of South Australia’s Human Research Ethics Committee (04-22-1001) and the University of Adelaide’s Human Research Ethics Committee. Prior to being recruited, all participants will be required to sign an informed consent form, which includes consent for the authors to publish the findings in the peer-reviewed scientific literature.
After completing informed consent with the assistance of the Aboriginal research staff, participants will be again asked to provide saliva samples using a commercially available kit from which microbial DNA and mRNA for genotyping will be extracted. This will involve the participant (1) not eating or drinking for 30 minutes prior to collection; (2) removing the funnel lid on the container; (3) spitting until 2 mL of saliva reaches the fill line on the container (this will take 2 minutes); (4) closing the lid and unscrewing the lid from the funnel; and (5) placing the small cap on the tube and shaking the tube for 5 seconds. The saliva samples will be sent to Victorian Cytology Services Ltd for analysis.
A thorough clinical examination of the external head and neck, intraoral cavity, and oropharynx will be undertaken by trained and calibrated dental professionals. Soft and hard tissue characteristics, caries experience, periodontal disease, and gingivitis will be assessed through standardized oral epidemiological examinations used in national oral health surveys. Weight will be measured in duplicate to the nearest 0.1 kg using Seca model 803 scales and averaged. Height will be measured in duplicate to the nearest 1 mm using a Seca model 213 portable stadiometer, using a standard anthropometric procedure. Any pathology detected via the clinical examination or saliva results will be immediately fed back to participants, with referrals to specialist or local primary care services promptly arranged.
Data collection will be at participants’ homes, ACCHOs, or wherever participants feel the most comfortable.
In brief, the analysis plan for each aim is as follows:
Saliva samples will be stabilized at the point of collection using PreservCyt media. Samples will be run on the real-time polymerase chain reaction–based Seegene HPV 28 assay using the Starlet extraction platform and the BioRad CFX96 amplification/detection instrument. The Seegene HPV 28 assay is the benchmark for HPV surveillance [
The prevalence, extent, and severity of dental diseases, including early clinical signs of OPSCC, will be calculated using standard World Health Organization (WHO) oral health benchmarks [
Of the 1011 participants recruited, 910 (90%) provided β-globin positive saliva samples (β-globin is a DNA integrity check). Of these 910, 35.1% (n=319) were positive for any HPV infection [
In our Indigenous Australian HPV Cohort study, of the 749 participants retained at 12-month follow-up, 645 (86.1%) provided β-globin positive saliva samples. Of these, 43% (277/645) were positive for any HPV infection. The most prevalent HPV types at 12-months were again those associated with Heck disease (213/645, 33% of the HPV types found), followed by HPV types associated with OPSCC (HPV 16 or 18; 16/645, 2.5%). A total of 588 participants had samples at baseline and 12-month follow-up that were β-globin positive. The prevalence of any oral HPV infection increased from 34% (200/588) to 44% (259/588). This increase was largely due to increases in HPV types 13 or 32 (Heck disease): from 20% (118/588) at baseline to 34% (200/588) at 12 months. The prevalence of HPV 16 or 18 decreased from 3.9% (23/588) at baseline to 2.7% (16/588) at 12 months. The prevalence of high-risk HPV types according to the IARC definition [
Participant follow-up for this study will commence in January 2023. We anticipate the first results to be submitted for publication 1 year following initial recruitment.
Our findings have potential to change the way in which OPSCC among Australian Indigenous adults is managed, with desired impacts including cost-savings on expensive cancer treatments; improved nutritional, social, and emotional outcomes; and improved quality of life for both Indigenous adults and the Indigenous community more broadly.
The strong Aboriginal partnership, engagement, and buy-in of the first study phase were reported against the Consolidated Criteria for Strengthening Reporting of Health Research involving Indigenous Peoples (CONSIDER) statement [
By December 2021, study participants had been followed for a median of 3.5 (range 3.0-3.9) years from baseline, allowing the analysis of short-term outcomes including oral HPV infection prevalence, quality of life, health state valuations of OPSCC, and incidence/clearance in the 12-24 months after baseline. There is not, however, sufficient follow-up to assess whether oral HPV infections, especially persistent high-risk HPV infections, lead to early-stage OPSCC and what the attributable risk from HPV will be. Continuing the largest Indigenous HPV cohort in the world to track oral HPV infection and to monitor the early stages of OPSCC is essential to yield critical information to include in the management armamentarium of health and well-being recommendations for Australia’s First Nations. It is especially relevant in light of the imminent rollout of self-sampling HPV testing initiatives in Australia.
There are 2 main strengths of the Indigenous Australian HPV Cohort study. The first of these has been the engagement of South Australia’s Aboriginal communities. This has contributed to the excellent recruitment and follow-up rate (approximately 749/1011, 74% to 815/1011, 80.6%), which needs to be taken into context. For example, this study has been undertaken over vast distances (travelling 700 km west, 400 km east, and 800 km north of the city of Adelaide), involving highly disadvantaged participants who have, in the past, not always enjoyed positive research interactions. The fact that over 1000 participants were recruited in less than 12 months demonstrates the widespread community support. The second strength is the multidisciplinary skill set of the team that is Aboriginal led. The main limitation is the lack of clinical examinations, anthropometrics, and samples to detect HPV 16-E6 antibodies that would yield important biomarker estimates, with funding not provided for this in the first 3 waves of the study.
In conclusion, by continuing the follow-up of the Indigenous Australian HPV Cohort, we will generate novel information regarding oral HPV exposure and OPSCC, including a range of cost-effectiveness modelling to ascertain cost-savings of extending HPV vaccination initiatives beyond what is currently available. This information has potential to vastly increase the relatively unknown causes of such dramatic HPV-related OPSCC incidence rates. Over the past 7 years, we have established excellent community buy-in with Aboriginal groups across South Australia. Everything is in place to continue the follow-up of this essential cohort, with findings likely to be game-changing in terms of influencing Indigenous HPV vaccination policy, oral HPV infections, OPSCC, health policy, and clinical guidelines throughout Australia and, indeed, the world.
Peer-review reports from the National Health and Medical Research Council - 2021 Clinical Trials and Cohort Studies - Australian Government (Canberra, Australia).
Aboriginal Community Controlled Health Organisation
Consolidated Criteria for Strengthening Reporting of Health Research involving Indigenous Peoples
human papillomavirus
International Agency for Research on Cancer
mitochondrial RNA
oropharyngeal squamous cell carcinoma
World Health Organization
Funding for this study is from a National Health and Medical Research Council (NHMRC) project grant (APP1120215). GG is supported by an NHMRC investigator grant (APP1176651). LJ is supported by an NHMRC research fellowship (APP1102587).
The data sets generated and/or analyzed during the current study are not publicly available due to privacy issues of the participants. Data are available from the corresponding author on reasonable request.
All authors are named investigators on the project; they all contributed to the intellectual input of the study design and in writing this protocol.
KC is co—principal investigator (PI) of an investigator-initiated trial of cervical screening, “Compass”, run by the Australian Centre for Prevention of Cervical Cancer (ACPCC), which is a government-funded not-for-profit charity. Compass receives infrastructure support from the Australian government and the ACPCC has received equipment and a funding contribution from Roche Molecular Diagnostics, USA.
KC is also co-PI on a major implementation program Elimination of Cervical Cancer in the Western Pacific which has received support from the Minderoo Foundation and the Frazer Family Foundation and equipment donations from Cepheid Inc.