HPV-FASTER: broadening the scope for prevention of HPV-related cancer

Cervical cancer in Africa, Latin America and the Caribbean and Asia: Regional inequalities and changing trends

The vast majority (86% or 453,000 cases) of the global burden of cervical cancer occurs in Africa, Latin America and the Caribbean and Asia, where one in nine new cancer cases are of the cervix. Although the disease has become rare in high-resource settings (e.g., in North America, parts of Europe, Japan) that have historically invested in effective screening programs, the patterns and trends are variable elsewhere. While favourable incidence trends have been recorded in many populations in Asia and Latin America and the Caribbean in the past decades, rising rates have been observed in sub-Saharan African countries, where high quality incidence series are available. The challenge for countries heavily affected by the disease in these regions is to ensure resource-dependent programmes of screening and vaccination are implemented to transform the situation, so that accelerated declines in cervical cancer are not the preserve of high-income countries, but become the norm in all populations worldwide.

HPV types in cervical cancer tissue in South Africa: A head-to-head comparison by mRNA and DNA tests

Accurate identification of human papillomavirus (HPV)-types in cervical cancer tissue may be important for tailoring tests for primary screening and types to be included in a vaccine. The aim of this study was to compare test-performance of a 45-type HPV deoxyribonucleic acid (DNA)-test with a 9-type HPV messenger ribonucleic acid (mRNA)-test in cervical cancer tissues.In a case-series design 188 women with diagnosed cervical cancer during the period January 2008 to July 1, 2011 at the Gynaecological Oncology Unit, University of Pretoria, South Africa were recruited to the study. After cases with negative internal controls for DNA/mRNA detection (n = 18) and unconfirmed histology (n = 3) of cervical cancer were excluded, 167 women remained eligible for analysis. We compared 45 DNA-types detected through general primer (GP)5/6 polymerase chain reaction (PCR) and reverse line blot (RLB) genotyping with a modified version of the mRNA test PreTect HPV-Proofer detecting 9 genotypes (16, 18, 31, 33, 35, 45, 51, 52, 58).Histological types were 92.2% squamous cell carcinoma, 4.8% adenocarcinoma, and 3.0% adenosquamous carcinoma. Overall, HPV was detected in 95.2% (159/167) of specimens. The DNA- and mRNA tests each rendered 153/167 (91.6%) HPV positive results. When restricting the analysis to the 9 high-risk HPV-types included in the mRNA test, 91.6% (153/167) and 88.0% (147/167) were positive by the mRNA- and DNA-tests (P = .28), respectively. After hierarchical categorization of 9 comparable types, we found concordance in 66 of 67 specimens for HPV16, 25 of 27 specimens for HPV18, 19 of 21 specimens for HPV45, and only in 33 of 45 for HPV31, 33, 35, 51, 52, 58. The positivity rate for the HPV types 16, 18, and 45 and the positivity rate for HPV 16, 18, 45, 33 and 35 by both tests was 66% to 68% and 80% to 83%, respectively.Overall and when considering established high-risk types, the mRNA test has at least as high detection rate as the DNA test. The mRNA test can be an appropriate research tool to describe causative HPV-types in cervical cancer tissue for health care planning purposes.

Ten-year immune persistence and safety of the HPV-16/18 AS04-adjuvanted vaccine in females vaccinated at 15-55 years of age

Women remain at risk of human papillomavirus (HPV) infection for most of their lives. The duration of protection against HPV-16/18 from prophylactic vaccination remains unknown. We investigated the 10-year immune response and long-term safety profile of the HPV-16/18 AS04-adjuvanted vaccine (AS04-HPV-16/18 vaccine) in females aged between 15 and 55 years at first vaccination. Females who received primary vaccination with three doses of AS04-HPV-16/18 vaccine in the primary phase-III study (NCT00196937) were invited to attend annual evaluations for long-term immunogenicity and safety. Anti-HPV-16/18 antibodies in serum and cervico-vaginal secretions (CVS) were measured using enzyme-linked immunosorbent assay (ELISA). Serious adverse events (SAEs) were recorded throughout the follow-up period. Seropositivity rates for anti-HPV-16 remained high (≥96.3%) in all age groups 10 years after first vaccination. It was found that 99.2% of 15-25-year olds remained seropositive for anti-HPV-18 compared to 93.7% and 83.8% of 26-45-year olds and 45-55-year olds, respectively. Geometric mean titers (GMT) remained above natural infection levels in all age groups. Anti-HPV-16 and anti-HPV-18 titers were at least 5.3-fold and 3.1-fold higher than titers observed after natural infection, respectively, and were predicted to persist above natural infection levels for ≥30 years in all age groups. At Year 10, anti-HPV-16/18 antibody titers in subjects aged 15-25 years remained above plateau levels observed in previous studies. Correlation coefficients for antibody titers in serum and CVS were 0.64 (anti-HPV-16) and 0.38 (anti-HPV-18). This study concluded that vaccinated females aged 15-55 years elicited sustained immunogenicity with an acceptable safety profile up to 10 years after primary vaccination, suggesting long-term protection against HPV.

Melatonin increases human cervical cancer HeLa cells apoptosis induced by cisplatin via inhibition of JNK/Parkin/mitophagy axis

Considering that chemotherapy resistance is vital to the progression of cervical carcinoma, emerging researchers are focused on developing anti-tumor drugs to assist the treatment efficiency of chemotherapy. Melatonin has anti-tumor activity via several mechanisms including its anti-proliferative and pro-apoptotic effects as well as its potent pro-oxidant action in tumor cells. Therefore, melatonin may be useful for the treatment of tumors in association with chemotherapy drugs. Here, we studied the effect and mechanism of melatonin on HeLa cells apoptosis under cisplatin (CIS) treatment, particularly focusing on the caspase-9-related apoptosis pathway and mitophagy-mediated anti-apoptotic mechanism. The result indicated that co-stimulation of HeLa cells with CIS in the presence of melatonin further increased cellular apoptosis. Furthermore, concomitant treatments with melatonin and CIS significantly enhanced the mitochondrial structure and function damage, substantially augmented the caspase-9-dependent mitochondrial apoptosis with evidenced by lower mitochondria membrane potential, higher mitochondria ROS, and more pro-apoptotic proteins compared to the treatment with CIS alone. Mechanistically, melatonin inactivated mitophagy via blockade of JNK/Parkin, leading to the inhibition of anti-apoptotic mitophagy. The mitophagy had the ability to clear and remove damaged mitochondria, impairing CIS-mediated mitochondrial apoptosis. Activation of JNK/Parkin could alleviate the lethal effect of melatonin on HeLa cells. In summary, this study confirmed that melatonin sensitizes human cervical cancer HeLa cells to CIS-induced apoptosis through inhibition of JNK/Parkin/mitophagy pathways.

Why Human Papillomavirus Acute Infections Matter

Most infections by human papillomaviruses (HPVs) are `acute', that is non-persistent. Yet, for HPVs, as for many other oncoviruses, there is a striking gap between our detailed understanding of chronic infections and our limited data on the early stages of infection. Here we argue that studying HPV acute infections is necessary and timely. Focusing on early interactions will help explain why certain infections are cleared while others become chronic or latent. From a molecular perspective, descriptions of immune effectors and pro-inflammatory pathways during the initial stages of infections have the potential to lead to novel treatments or to improved handling algorithms. From a dynamical perspective, adopting concepts from spatial ecology, such as meta-populations or meta-communities, can help explain why HPV acute infections sometimes last for years. Furthermore, cervical cancer screening and vaccines impose novel iatrogenic pressures on HPVs, implying that anticipating any viral evolutionary response remains essential. Finally, hints at the associations between HPV acute infections and fertility deserve further investigation given their high, worldwide prevalence. Overall, understanding asymptomatic and benign infections may be instrumental in reducing HPV virulence.

Optimizing secondary prevention of cervical cancer: Recent advances and future challenges

Although human papillomavirus (HPV) vaccines offer enormous promise for the ultimate control and possible elimination of cervical cancer, barriers to uptake and coverage of the vaccine both in high- and low/middle-income settings mean that advances in secondary prevention continue to be essential to prevent unnecessary deaths and suffering from cervical cancer for decades to come. While cytology (the Pap smear) has reduced cervical cancer incidence and prevalence in jurisdictions where it has been systematically implemented in population-based programs-mainly in high-income settings-limitations inherent to this method, and to program delivery, leave many women still vulnerable to cervical cancer. Recent evidence has confirmed that screening based on HPV testing prevents more invasive cervical cancer and precancerous lesions, and offers innovative options such as self-collection of specimens to improve screening uptake broadly. In this paper, we review key advances, future opportunities, and ongoing challenges for secondary prevention of cervical cancer using HPV-based testing.

Cervical Cancer Prevention Through HPV Vaccination in Low- and Middle-Income Countries in Asia

Cervical cancer is ranked the first or second most common cancer in women of low- and middle-income countries (LMICs) in Asia. Cervical cancer is almost exclusively caused by human papillomavirus (HPV), and majority of the cases can be prevented with the use of HPV vaccines. The HPV vaccines have demonstrated high vaccine efficacies against HPV infection and cervical cancer precursors in clinical and post-marketing studies, and are in use in most high-income countries. However, their use in LMICs are limited mainly due to the high costs and logistics in delivering multiple doses of the vaccine. Other issues such as the safety of the vaccines, social and cultural factors, as well as poor knowledge and awareness of the virus have also contributed to the low uptake of the vaccine. This mini-review focuses on the need for HPV vaccine implementation in Asia given the substantial disease burden and underuse of HPV vaccines in LMICs in this region. In addition, the progress towards HPV vaccine introduction, and barriers preventing further rollout of these essential, life-saving vaccines are also discussed in this article.

Natural History of HPV Infection across the Lifespan: Role of Viral Latency

Large-scale epidemiologic studies have been invaluable for elaboration of the causal relationship between persistent detection of genital human papillomavirus (HPV) infection and the development of invasive cervical cancer. However, these studies provide limited data to adequately inform models of the individual-level natural history of HPV infection over the course of a lifetime, and particularly ignore the biological distinction between HPV-negative tests and lack of infection (i.e., the possibility of latent, undetectable HPV infection). Using data from more recent epidemiological studies, this review proposes an alternative model of the natural history of genital HPV across the life span. We argue that a more complete elucidation of the age-specific probabilities of the alternative transitions is highly relevant with the expanded use of HPV testing in cervical cancer screening. With routine HPV testing in cervical cancer screening, women commonly transition in and out of HPV detectability, raising concerns for the patient and the provider regarding the source of the positive test result, its prognosis, and effective strategies to prevent future recurrence. Alternative study designs and analytic frameworks are proposed to better understand the frequency and determinants of these transition pathways.

Ten-year follow-up of human papillomavirus vaccine efficacy against the most stringent cervical neoplasia end-point-registry-based follow-up of three cohorts from randomized trials

OBJECTIVE

Due to long lag time between infection/cancer diagnoses human papillomavirus (HPV) vaccination programs will deliver vaccine efficacy (VE) estimates against cancer end-points late. Cancer registry follow-up of population-based, randomised trial cohorts of vaccinated and unvaccinated women was undertaken for the estimation of VE against cervical intraepithelial neoplasia grade three and invasive cancer (CIN3+).

METHODS

We report interim results with 98 561 person years of Finnish Cancer Registry -based follow-up of individually and/or cluster randomised cohorts of HPV-16/18 vaccinated and unvaccinated adolescent women enrolled in June 2003/2005, and between May 2004 and April 2005, respectively. The cohorts comprised 15 627 18- to 19-year-old unvaccinated women (NCT01393470), and 2 401 and 64 16- to 17-year-old HPV-16/18 vaccinated women participating the PATRICIA (NCT00122681) and HPV-012 (NCT00169494) trials, respectively. The age-aligned passive follow-up started 6 months after the clinical trials' end.

RESULTS

During the follow-up of 4.5 to 10 years post enrolment we identified 75 cases of cervical intraepithelial neoplasia grade 3 (CIN3) and 4 cases of invasive cervical cancer (ICC) in the unvaccinated cohort, and 4 CIN3 cases in the HPV-16/18 vaccinated women. Diagnostic blocks were available for HPV typing from 87% of the cases. CIN3+ lesions were detectable in 54 cases. HPV16 was found in 26 of 50 unvaccinated CIN3+ cases, and in 3 CIN3+ cases in the HPV-16/18 vaccinated women. The latter were all baseline positive for cervical HPV16 DNA. Baseline data was not available for the unvaccinated women. Intention-to-treat VE against any CIN3+ was 66% (95% CI 8, 88).

CONCLUSIONS

Ten years post vaccination the AS04-adjuvanted HPV-16/18 vaccine shows continued efficacy against CIN3+ irrespectively of HPV type. Vaccine efficacy was not observed in baseline HPV16 DNA positive subjects.

TRIAL REGISTRATION NUMBER

NCT01393470.

Worldwide burden of cancer attributable to HPV by site, country and HPV type

HPV is the cause of almost all cervical cancer and is responsible for a substantial fraction of other anogenital cancers and oropharyngeal cancers. Understanding the HPV-attributable cancer burden can boost programs of HPV vaccination and HPV-based cervical screening. Attributable fractions (AFs) and the relative contributions of different HPV types were derived from published studies reporting on the prevalence of transforming HPV infection in cancer tissue. Maps of age-standardized incidence rates of HPV-attributable cancers by country from GLOBOCAN 2012 data are shown separately for the cervix, other anogenital tract and head and neck cancers. The relative contribution of HPV16/18 and HPV6/11/16/18/31/33/45/52/58 was also estimated. 4.5% of all cancers worldwide (630,000 new cancer cases per year) are attributable to HPV: 8.6% in women and 0.8% in men. AF in women ranges from <3% in Australia/New Zealand and the USA to >20% in India and sub-Saharan Africa. Cervix accounts for 83% of HPV-attributable cancer, two-thirds of which occur in less developed countries. Other HPV-attributable anogenital cancer includes 8,500 vulva; 12,000 vagina; 35,000 anus (half occurring in men) and 13,000 penis. In the head and neck, HPV-attributable cancers represent 38,000 cases of which 21,000 are oropharyngeal cancers occurring in more developed countries. The relative contributions of HPV16/18 and HPV6/11/16/18/31/33/45/52/58 are 73% and 90%, respectively. Universal access to vaccination is the key to avoiding most cases of HPV-attributable cancer. The preponderant burden of HPV16/18 and the possibility of cross-protection emphasize the importance of the introduction of more affordable vaccines in less developed countries.

Progress in prophylactic human papillomavirus (HPV) vaccination in 2016: A literature review

Prophylactic human papillomavirus (HPV) vaccine represents a revolutionary step forward in preventing HPV-related cancers, especially cervical carcinoma. Alongside appropriate screening, it has the potential to dramatically reduce cervical cancer incidence and even eradicate it. Following extensive evaluations in clinical trials, the first decade of routine HPV vaccine use provides overwhelming evidence of the vaccines' safety and their real-life effectiveness. In 2016, further clinical trials showed high vaccine efficacy in adult women, especially those that were HPV DNA-negative at baseline, and indicated possible protection from HPV-related diseases after treatment of precancerous cervical lesions. The recommendation for a two-dose schedule in individuals under 15 is further supported for all three licensed vaccines by immunogenicity studies that show non-inferior immune responses and similar clinical efficacy compared to the three-dose schedule. So far, natural competition between HPV types has not been confirmed and therefore vaccine-induced clinically significant type replacement is unlikely. The real-world effectiveness data showed cross-sectional reduction in the prevalence/incidence of vaccine-related HPV types, genital warts and precancerous cervical lesions in countries and regions with HPV vaccination coverage. These declines were evident not only in vaccinated females, but also in unvaccinated females and males, strongly suggesting herd protection. Despite an excellent safety profile consistently demonstrated in clinical trials and confirmed in real-life settings, recently invented controversial syndromes allegedly linked to HPV vaccines temporarily compromised some previously very successful vaccination programs and significantly contributed to the failure of HPV vaccine implementation in some countries with the highest prevalence of cervical cancer. However, several safety studies failed to confirm any association of these syndromes with HPV vaccination in various settings and geographic locations. The main challenges remain implementing HPV vaccination in national vaccination programs, especially in low-and middle-income countries with the highest burden of cervical cancer, and achieving and sustaining high vaccine coverage rates.

Psycho-social influences upon older women's decision to attend cervical screening: A review of current evidence

Cervical cancer is the fourth most common cancer in women worldwide (WHO, 2016). In many developed countries the incidence of cervical cancer has been significantly reduced by the introduction of organised screening programmes however, in the UK, a fall in screening coverage is becoming a cause for concern. Much research attention has been afforded to younger women but age stratified mortality and incidence data suggest that older women's screening attendance is also worthy of study. This paper provides a review of current evidence concerning the psycho-social influences that older women experience when deciding whether to attend cervical screening. Few studies have focussed on older women and there are significant methodological issues with those that have included them in their samples. Findings from these studies indicate several barriers which may deter older women from screening, such as embarrassment and logistical issues. Drivers to screening include reassurance and a sense of obligation. Physical, social and emotional changes that occur as women age may also have an impact on attendance. This review concludes that there is a clear need for better understanding of the perceptions of older women specifically with regard to cervical cancer and screening. Future research should inform the design of targeted interventions and provision of information to enable informed decision-making regarding cervical screening among older women.

Human papillomavirus E7 protein detection as a method of triage to colposcopy of HPV positive women, in comparison to genotyping and cytology. Final results of the PIPAVIR study

The objective of the presented cross-sectional-evaluation-screening study is the clinical evaluation of high-risk(hr)HPVE7-protein detection as a triage method to colposcopy for hrHPV-positive women, using a newly developed sandwich-ELISA-assay. Between 2013-2015, 2424 women, 30-60 years old, were recruited at the Hippokratio Hospital, Thessaloniki/Greece and the Im Mare Klinikum, Kiel/Germany, and provided a cervical sample used for Liquid Based Cytology, HPV DNA genotyping, and E7 detection using five different E7-assays: "recomWell HPV16/18/45KJhigh", "recomWell HPV16/18/45KJlow", "recomWell HPV39/51/56/59", "recomWell HPV16/31/33/35/52/58" and "recomWell HPVHRscreen" (for 16,18,31,33,35,39,45,51,52,56,58,59 E7), corresponding to different combinations of hrHPVE7-proteins. Among 1473 women with eligible samples, those positive for cytology (ASCUS+ 7.2%), and/or hrHPV DNA (19.1%) were referred for colposcopy. Cervical Intraepithelial Neoplasia grade 2 or worse (CIN2+) was detected in 27 women (1.8%). For HPV16/18-positive women with no triage, sensitivity, positive predictive value (PPV) and the number of colposcopies needed to detect one case of CIN2+ were 100.0%, 11.11% and 9.0 respectively. The respective values for E7-testing as a triage method to colposcopy ranged from 75.0-100.0%, 16.86-26.08% and 3.83-5.93. Sensitivity and PPV for cytology as triage for hrHPV(non16/18)-positive women were 45.45% and 27.77%; for E7 test the respective values ranged from 72.72-100.0% and 16.32-25.0%. Triage of HPV 16/18-positive women to colposcopy with the E7 test presents better performance than no triage, decreasing the number of colposcopies needed to detect one CIN2+. In addition, triage of hrHPV(non16/18)-positive women with E7 test presents better sensitivity and slightly worse PPV than cytology, a fact that advocates for a full molecular screening approach.

Human papillomavirus vaccination: the population impact

We currently have the knowledge and experience to prevent much of human papillomavirus (HPV)-related disease burden globally. In many countries where prophylactic HPV vaccination programs have been adopted as highly effective public health programs with good vaccine coverage, we are already seeing, in real-world settings, reduction of vaccine-related HPV-type infections, genital warts and cervical pre-cancers with potential reductions in vulvar, vaginal and anal pre-cancers. Moreover, we are seeing a change in cervical screening paradigms, as HPV-based screening programs now have strong evidence to support their use as more sensitive ways to detect underlying cervical abnormalities, as compared with conventional cervical cytology. This article describes the impact of prophylactic vaccination on these outcomes and in settings where these vaccines have been implemented in national immunisation programs. Given the successes seen to date and the availability of essential tools, there has been a global push to ensure that every woman has access to effective cervical screening and every girl has the opportunity for primary prevention through vaccination. A gender-neutral approach by offering vaccination to young boys has also been adopted by some countries and is worthy of consideration given that HPV-related cancers also affect males. Furthermore, vaccination of young boys has the advantage of reducing the risk of HPV transmission to sexual partners, lowering the infectious pool of HPV in the general population and ultimately HPV-related diseases for both genders. Therefore, it is appropriate that all countries consider and promote national guidelines and programs to prevent HPV-related diseases.

Cervical cancer screening in the era of HPV vaccination: A review of shifting paradigms in cytopathology

Significant changes in cervical cancer screening practice, guidelines, and prevention of cervical cancer have taken place in recent years including the raising of initial cervical cancer screening age, changes in frequency of cytology screening, and the adoption of high risk HPV and cytology co-testing for some patients; the introduction of the bivalent, quadrivalent, and 9-valent HPV vaccines; and the recent approval of high risk HPV testing as primary screening with the use of cytology as triage in positive cases. This review discusses the significance of primary HPV screening, the impact of HPV vaccination in the prevalence of cervical cancer and its precursors, the interplay between high risk HPV testing and vaccination, and the implications for clinical and cytological management. Future strategies for cervical screening in the post-vaccination era are also discussed.

Vaccination to prevent human papillomavirus infections: From promise to practice

In an essay, Paul Bloem and Ikechukwu Ogbuanu discuss the public health implications of HPV vaccination.

[Human papillomavirus nonavalent vaccine. Update 2017]

Human papillomavirus (HPV) is the causative agent of 5% of human cancers. HPV infection is necessary for the development of cervical cancer and is responsible of a variable percentage of cancers of anus, vulva, vagina, penis, and oropharynx. Since 2007, 2 vaccines against HPV have been commercially available in Spain: bivalent (HPV types 16/18), and tetravalent (HPV types 6/11/16/18). In order to extend the protection afforded by HPV vaccines, a clinical program was launched in 2006 for the new nonavalent vaccine, including 9 HPV types (6/11/16/18/31/33/45/52/58). These types are responsible for 90% of cervical cancers, 82% of high-grade ano-genital pre-cancerous lesions, and 90% of genital warts. The purpose of this publication is to provide healthcare professionals with the scientific evidence that supports the new vaccine, as well as the clinical value that it offers in our environment.

Considerations for HPV primary screening in lower-middle income countries

The accumulated scientific evidence now provides ample support for HPV primary screening as a superior method for detecting cervical precancer and preventing cervical cancer. Approximately half of the global burden of cervical cancer could be reduced in lower-middle income countries where attempts to implement traditional cytology-based programs have not experienced successes. In these countries screening programs have struggled with poor screening and diagnostic test sensitivity, difficulties maintaining quality control and adequate population coverage. HPV testing is not only more accurate and reliable, but also requires less training, quality assurance and expensive personnel. Because these countries are especially vulnerable to economic, political and societal instabilities, HPV tests must become more affordable and accessible in order to enable Ministries of Health to make long-term resource commitments.

HPV vaccines - A review of the first decade

Pre-adolescent girls (9-15years) have the option of receiving a two dose HPV vaccine series at either a six month or one year interval to provide protection from HPV 16, the most prevalent type associated with cervical cancers, as well as several other less prevalent types. This series of vaccinations is highly likely to protect her from HPV infection until she enters the routine screening program, whether that be primary HPV testing or a combination of HPV testing and cytology. The two dose program has been recommended by the World Health Organization (WHO) since 2015. For women 15years and older, the three dose vaccine schedule is still recommended. The past ten years of Gardasil use has provided evidence of reduced HPV 16/18 infections in countries where there has been high coverage. Gardasil9 has replaced Gardasil. Gardasil9 has the same rapid anti-HPV 18 and HPV45 titer loss as Gardasil did. Cervarix remains equivalent to Gardasil9 in the prevention of HPV infections and precancers of any HPV type; Cervarix also has demonstrated sustained high antibody titers for at least 10years. One dose of Cervarix provides protection against HPV 16/18 infection with robust antibody titers well above natural infection titers. This may offer the easiest and most cost effective vaccination program over time, especially in low and lower middle income countries. Cervical cancer screening must continue to control cancer incidence over the upcoming decades. Future studies of prophylactic HPV vaccines, as defined by the WHO, must demonstrate protection against six month type specific persistent infections, not actual cervical cancer precursor disease endpoints, such as cervical intraepithelial neoplasia grade 3 (CIN 3) or adenocarcinoma in situ (AIS). This simplifies and makes less expensive future comparative studies between existing and new generic vaccines.

Molecular tests potentially improving HPV screening and genotyping for cervical cancer prevention

INTRODUCTION

Human papillomavirus (HPV)-related cancers can be averted by type-specific vaccination (primary prevention) and/or through detection and ablation of precancerous cervical lesions (secondary prevention). This review presents current challenges to cervical cancer screening programs, focusing on recent molecular advances in HPV testing and potential improvements on risk stratification. Areas covered: High-risk (HR)-HPV DNA detection has been progressively incorporated into cervix cancer prevention programs based on its increased sensitivity. Advances in next-generation sequencing (NGS) are being rapidly applied to HPV typing. However, current HPV DNA tests lack specificity for identification of cervical precancer (CIN3). HPV typing methods were reviewed based on published literature, with a focus on these applications for screening and risk stratification in the emerging complex clinical scenario post-vaccine introduction. In addition, the potential for NGS technologies to increase specificity is discussed in regards to reflex testing of specimens for emerging biomarkers for cervix precancer/cancer. Expert commentary: Integrative multi-disciplinary molecular tests accurately triaging exfoliated cervical specimens will improve cervical cancer prevention programs while simplifying healthcare procedures in HPV-infected women. Hence, the concept of a 'liquid-biopsy' (i.e., 'molecular' Pap test) highly specific for early identification of cervical precancerous lesions is of critical importance in the years to come.

Mechanistic mathematical models: An underused platform for HPV research

Health economic modeling has become an invaluable methodology for the design and evaluation of clinical and public health interventions against the human papillomavirus (HPV) and associated diseases. At the same time, relatively little attention has been paid to a different yet complementary class of models, namely that of mechanistic mathematical models. The primary focus of mechanistic mathematical models is to better understand the intricate biologic mechanisms and dynamics of disease. Inspired by a long and successful history of mechanistic modeling in other biomedical fields, we highlight several areas of HPV research where mechanistic models have the potential to advance the field. We argue that by building quantitative bridges between biologic mechanism and population level data, mechanistic mathematical models provide a unique platform to enable collaborations between experimentalists who collect data at different physical scales of the HPV infection process. Through such collaborations, mechanistic mathematical models can accelerate and enhance the investigation of HPV and related diseases.

Carcinogenic human papillomavirus infection

Infections with human papillomavirus (HPV) are common and transmitted by direct contact. Although the great majority of infections resolve within 2 years, 13 phylogenetically related, sexually transmitted HPV genotypes, notably HPV16, cause - if not controlled immunologically or by screening - virtually all cervical cancers worldwide, a large fraction of other anogenital cancers and an increasing proportion of oropharyngeal cancers. The carcinogenicity of these HPV types results primarily from the activity of the oncoproteins E6 and E7, which impair growth regulatory pathways. Persistent high-risk HPVs can transition from a productive (virion-producing) to an abortive or transforming infection, after which cancer can result after typically slow accumulation of host genetic mutations. However, which precancerous lesions progress and which do not is unclear; the majority of screening-detected precancers are treated, leading to overtreatment. The discovery of HPV as a carcinogen led to the development of effective preventive vaccines and sensitive HPV DNA and RNA tests. Together, vaccination programmes (the ultimate long-term preventive strategy) and screening using HPV tests could dramatically alter the landscape of HPV-related cancers. HPV testing will probably replace cytology-based cervical screening owing to greater reassurance when the test is negative. However, the effective implementation of HPV vaccination and screening globally remains a challenge.

Preventable fractions of cervical cancer via effective screening in six Baltic, central, and eastern European countries 2017-40: a population-based study

BACKGROUND

Cervical cancer incidence remains high in several Baltic, central, and eastern European (BCEE) countries, mainly as a result of a historical absence of effective screening programmes. As a catalyst for action, we aimed to estimate the number of women who could be spared from cervical cancer across six countries in the region during the next 25 years, if effective screening interventions were introduced.

METHODS

In this population-based study, we applied age-period-cohort models with spline functions within a Bayesian framework to incidence data from six BCEE countries (Estonia, Latvia, Lithuania, Belarus, Bulgaria, and Russia) to develop projections of the future number of new cases of cervical cancer from 2017 to 2040 based on two future scenarios: continued absence of screening (scenario A) versus the introduction of effective screening from 2017 onwards (scenario B). The timespan of available data varied from 16 years in Bulgaria to 40 years in Estonia. Projected rates up to 2040 were obtained in scenario A by extrapolating cohort-specific trends, a marker of changing risk of human papillomavirus (HPV) infection, assuming a continued absence of effective screening in future years. Scenario B added the effect of gradual introduction of screening in each country, under the assumption period effects would be equivalent to the decreasing trend by calendar year seen in Denmark (our comparator country) since the progressive regional introduction of screening from the late 1960s.

FINDINGS

According to scenario A, projected incidence rates will continue to increase substantially in many BCEE countries. Very high age-standardised rates of cervical cancer are predicted in Lithuania, Latvia, Belarus, and Estonia (up to 88 cases per 100 000). According to scenario B, the beneficial effects of effective screening will increase progressively over time, leading to a 50-60% reduction of the projected incidence rates by around 2040, resulting in the prevention of cervical cancer in 1500 women in Estonia and more than 150 000 women in Russia. The immediate launch of effective screening programmes could prevent almost 180 000 new cervical cancer diagnoses in a 25-year period in the six BCEE countries studied.

INTERPRETATION

Based on our findings, there is a clear need to begin cervical screening in these six countries as soon as possible to reduce the high and increasing incidence of cervical cancer over the next decades.

FUNDING

None.

Prior human papillomavirus-16/18 AS04-adjuvanted vaccination prevents recurrent high grade cervical intraepithelial neoplasia after definitive surgical therapy: Post-hoc analysis from a randomized controlled trial

We evaluated the efficacy of the human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine in preventing HPV-related disease after surgery for cervical lesions in a post-hoc analysis of the PApilloma TRIal against Cancer In young Adults (PATRICIA; NCT00122681). Healthy women aged 15-25 years were randomized (1:1) to receive vaccine or control at months 0, 1 and 6 and followed for 4 years. Women were enrolled regardless of their baseline HPV DNA status, HPV-16/18 serostatus, or cytology, but excluded if they had previous or planned colposcopy. The primary and secondary endpoints of PATRICIA have been reported previously; the present post-hoc analysis evaluated efficacy in a subset of women who underwent an excisional procedure for cervical lesions after vaccination. The main outcome was the incidence of subsequent HPV-related cervical intraepithelial neoplasia grade 2 or greater (CIN2+) 60 days or more post-surgery. Other outcomes included the incidence of HPV-related CIN1+, and vulvar or vaginal intraepithelial neoplasia (VIN/VaIN) 60 days or more post-surgery. Of the total vaccinated cohort of 18,644 women (vaccine = 9,319; control = 9,325), 454 (vaccine = 190, control = 264) underwent an excisional procedure during the trial. Efficacy 60 days or more post-surgery for a first lesion, irrespective of HPV DNA results, was 88.2% (95% CI: 14.8, 99.7) against CIN2+ and 42.6% (-21.1, 74.1) against CIN1+. No VIN was reported and one woman in each group had VaIN2+ 60 days or more post-surgery. Women who undergo surgical therapy for cervical lesions after vaccination with the HPV-16/18 vaccine may continue to benefit from vaccination, with a reduced risk of developing subsequent CIN2+.

Validation of Novaprep(®) HQ+ liquid-based cytology medium for high-risk human papillomavirus detection by hc2

Background

Preanalytical conditions determine the reliability and validity of bioassays. Therefore, the analytic performances of biological tests need to be determined when preanalytical steps differ from those recommended by the manufacturer. The objective of the study was to assess the analytic performance of the hc2 test for the detection of high-risk HPV DNA from cells stored in the new Novaprep® HQ+ medium.

Methods

Repeatability, reproducibility, method comparison and stability (-20 °C, +4 °C, +20 °C and +40 °C up to six months) were evaluated from HPV16 and HPV18 positive cell lines diluted in the Novaprep® HQ+ medium and the reference Specimen Transport Medium (STM). A series of cervical samples with atypical squamous cells of undetermined significance (ASC-US) cytology and stored in the Novaprep® HQ+ medium was also tested.

Results

Coefficients of variation for repeatability and reproducibility were less than 8 %. Method comparison showed perfect agreement in hc2 results when the HPV-positive cells were diluted in HQ+ and reference media. Stability experiments demonstrated that the storage conditions did not alter the hc2 test results. Furthermore, clinical samples were adequately preserved for hc2 testing.

Conclusions

Overall, our data show that the new Novaprep HQ+ medium is suitable for high-risk HPV testing by hc2.

Efficacy, safety, and immunogenicity of the human papillomavirus 16/18 AS04-adjuvanted vaccine in women older than 25 years: 7-year follow-up of the phase 3, double-blind, randomised controlled VIVIANE study

BACKGROUND

Although the risk of human papillomavirus (HPV) infection is greatest in young women, women older than 25 years remain at risk. We present data from the VIVIANE study of the HPV 16/18 AS04-adjuvanted vaccine in adult women after 7 years of follow-up.

METHODS

In this phase 3, double-blind, randomised controlled trial, healthy women older than 25 years were enrolled (age stratified: 26-35 years, 36-45 years, and ≥46 years). Up to 15% in each age stratum had a history of HPV infection or disease. Women were randomly assigned (1:1) to receive HPV 16/18 vaccine or aluminium hydroxide control, with an internet-based system. The primary endpoint was vaccine efficacy against 6-month persistent infection or cervical intraepithelial neoplasia grade 1 or greater (CIN1+) associated with HPV 16/18. We did analyses in the according-to-protocol cohort for efficacy and total vaccinated cohort. Data for the combined primary endpoint in the according-to-protocol cohort for efficacy were considered significant when the lower limit of the 96·2% CI around the point estimate was greater than 30%. For all other endpoints and cohorts, data were considered significant when the lower limit of the 96·2% CI was greater than 0%. This study is registered with ClinicalTrials.gov, number NCT00294047.

FINDINGS

The first participant was enrolled on Feb 16, 2006, and the last study visit took place on Jan 29, 2014. 4407 women were in the according-to-protocol cohort for efficacy (n=2209 vaccine, n=2198 control) and 5747 women in the total vaccinated cohort (n=2877 vaccine, n=2870 control). At month 84, in women seronegative for the corresponding HPV type in the according-to-protocol cohort for efficacy, vaccine efficacy against 6-month persistent infection or CIN1+ associated with HPV 16/18 was significant in all age groups combined (90·5%, 96·2% CI 78·6-96·5). Vaccine efficacy against HPV 16/18-related cytological abnormalities (atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion) and CIN1+ was also significant. We also noted significant cross-protective efficacy against 6-month persistent infection with HPV 31 (65·8%, 96·2% CI 24·9-85·8) and HPV 45 (70·7%, 96·2% CI 34·2-88·4). In the total vaccinated cohort, vaccine efficacy against CIN1+ irrespective of HPV was significant (22·9%, 96·2% CI 4·8-37·7). Serious adverse events related to vaccination occurred in five (0·2%) of 2877 women in the vaccine group and eight (0·3%) of 2870 women in the control group.

INTERPRETATION

In women older than 25 years, the HPV 16/18 vaccine continues to protect against infections, cytological abnormalities, and lesions associated with HPV 16/18 and CIN1+ irrespective of HPV type, and infection with non-vaccine types HPV 31 and HPV 45 over 7 years of follow-up.

FUNDING

GlaxoSmithKline Biologicals SA.

Immunologic approaches to cancer prevention-current status, challenges, and future perspectives

The potential of the immune system to recognize and reject tumors has been investigated for more than a century. However, only recently impressive breakthroughs in cancer immunotherapy have been seen with the use of checkpoint inhibitors. The experience with various immune-based strategies in the treatment of late cancer highlighted the importance of negative impact advanced disease has on immunity. Consequently, use of immune modulation for cancer prevention rather than therapy has gained considerable attention, with many promising results seen already in preclinical and early clinical studies. Although not without challenges, these results provide much excitement and optimism that successful cancer immunoprevention could be within our reach. In this review we will discuss the current state of predominantly primary and secondary cancer immunoprevention, relevant research, potential barriers, and future directions.