Human papillomavirus (HPV) genotypes in an Australian sample of anal cancers

Understanding the HPV associated cancers: A comprehensive review

Human papillomavirus (HPV), a common cause of sexually transmitted diseases, may cause warts and lead to various types of cancers, which makes it important to understand the risk factors associated with it. HPV is the leading risk factor and plays a crucial role in the progression of cervical cancer. Viral oncoproteins E6 and E7 play a pivotal role in this process. Beyond cervical cancer, HPV-associated cancers of the mouth and throat are also increasing. HPV can also contribute to other malignancies like penile, vulvar, and vaginal cancers. Emerging evidence links HPV to these cancers. Research on the oncogenic effect of HPV is still ongoing and explorations of screening techniques, vaccination, immunotherapy and targeted therapeutics are all in progress. The present review offers valuable insight into the current understanding of the role of HPV in cancer and its potential implications for treatment and prevention in the future.

Identifying Predictors of Anal HPV Status in HPV-Vaccinated MSM: A Machine Learning Approach

Anal human papillomavirus (HPV) infection has a high prevalence in men who have sex with men (MSM), resulting in an increased risk for anal cancer. The present work aimed to identify factors associated with HPV in a prospective cohort of HPV-vaccinated MSM using a random forest (RF) approach. This observational study enrolled MSM patients admitted to an Italian (sexually transmitted infection) STI-AIDS Unit. For each patient, rectal swabs for 28 different HPV genotype detection were collected. Two RF algorithms were applied to evaluate predictors that were most associated with HPV. The cohort included 135 MSM, 49% of whom were HIV-positive with a median age of 39 years. In model 1 (baseline information), age, age sexual debut, HIV, number of lifetime sex partners, STIs, were most associated with the HPV. In model 2 (follow-up information), age, age sexual debut, HIV, STI class, and follow-up. The RF algorithm exhibited good performances with 61% and 83% accuracy for models 1 and 2, respectively. Traditional risk factors for anal HPV infection, such as drug use, receptive anal intercourse, and multiple sexual partner, were found to have low importance in predicting HPV status. The present results suggest the need to focus on HPV prevention campaigns.

Anal High-risk Human Papillomavirus Infection, Squamous Intraepithelial Lesions, and Anal Cancer in Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

BACKGROUND

Ulcerative colitis [UC] and Crohn's disease [CD] can be associated with severe comorbidities, namely opportunistic infections and malignancies. We present the first systematic review and meta-analysis evaluating the burden of anal human papillomavirus disease in patients with UC and CD.

METHODS

PubMed, Web of Science, and Scopus were searched until November 2022. Meta-analyses were performed using random effects models. The protocol was recorded at PROSPERO register with the number CRD42022356728.

RESULTS

Six studies, including 78 711 patients with UC with a total follow-up of 518 969 person-years, described the anal cancer incidence rate. For anal cancer incidence rate in CD, six studies were selected, including 56 845 patients with a total follow-up of 671 899 person-years. The incidence of anal cancer was 10.2 [95% CI 4.3 - 23.7] per 100 000 person-years in UC and 7.7 [3.5 - 17.1] per 100 000 person-years in CD. A subgroup analysis of anal cancer in perianal CD, including 7105 patients, was calculated with incidence of 19.6 [12.2 - 31.6] per 100 000 person-years [three studies included]. Few studies described prevalence of anal cytological abnormalities [four studies including 349 patients] or high-risk human papillomavirus [three studies including 210 patients], with high heterogeneity. Prevalence of cytological abnormalities or high-risk human papillomavirus was not associated with pharmacological immunosuppression in the studies included.

CONCLUSION

The incidence of anal cancer is higher in UC than in CD, with the exception of perianal CD. There are limited and heterogeneous data on anal high-risk human papillomavirus infection and squamous intraepithelial lesions prevalence in this population.

Global burden of HPV-attributable squamous cell carcinoma of the anus in 2020, according to sex and HIV status: A worldwide analysis

Squamous cell carcinoma of the anus (SCCA) is caused by HPV, and is elevated in persons living with HIV (PLWHIV). We aimed to estimate sex- and HIV-stratified SCCA burden at a country, regional and global level. Using anal cancer incidence estimates from 185 countries available through GLOBOCAN 2020, and region/country-specific proportions of SCCA vs non-SCCA from the Cancer Incidence in Five Continents (CI5) Volume XI database, we estimated country- and sex-specific SCCA incidence. Proportions of SCCA diagnosed in PLWHIV, and attributable to HIV, were calculated using estimates of HIV prevalence (UNAIDS 2019) and relative risk applied to SCCA incidence. Of 30 416 SCCA estimated globally in 2020, two-thirds occurred in women (19 792) and one-third among men (10 624). Fifty-three percent of male SCCA and 65% of female SCCA occurred in countries with a very high Human Development Index (HDI). Twenty-one percent of the global male SCCA burden occurred in PLWHIV (n = 2203), largely concentrated in North America, Europe and Africa. While, only 3% of global female SCCA burden (n = 561) occurred in PLWHIV, mainly in Africa. The global age-standardized incidence rate of HIV-negative SCCA was higher in women (0.55 cases per 100 000) than men (0.28), whereas HIV-positive SCCA was higher in men (0.07) than women (0.02). HIV prevalence reached >40% in 22 countries for male SCCA and in 10 countries for female SCCA, mostly in Africa. Understanding global SCCA burden by HIV status can inform SCCA prevention programs (through HPV vaccination, screening and HIV control) and help raise awareness to combat the disease.

Anal Cancer Screening and Prevention: Summary of Evidence Reviewed for the 2021 Centers for Disease Control and Prevention Sexually Transmitted Infection Guidelines

In June 2019 the Centers for Disease Control and Prevention (CDC) convened an advisory group to assist in development of the 2021 CDC sexually transmitted infections (STI) guidelines. The advisory group on anal cancer screening and prevention met to formulate key questions in this field. The group examined published literature and abstracts to assess evidence and give recommendations for development of the CDC guidelines. This article summarizes key questions, evidence, recommendations, and areas for further research for the screening, diagnosis, and prevention of anal cancer.

Evaluating the Jaccard Similarity Index as a Persistence Measure of Multiple Anal Human Papillomavirus Among Nigerian Men Who Have Sex With Men

BACKGROUND

Multiple anal human papillomavirus (HPVs) may increase the risk of anal cancer among men who have sex with men (MSM) living with human immunodeficiency virus (HIV). The Jaccard Similarity Index (JSI) was explored as a measure of multiple HPV persistence.

METHODS

The TRUST/RV368 cohort enrolled MSM living with and without HIV in Abuja and Lagos, Nigeria. Participants with anal swabs at baseline, 3- and 12-month visits were tested for high- and low-risk HPVs using a next-generation sequencing assay. Persistence of the same HPV genotypes over time was calculated using the JSI and categorized into high, medium, and low similarity tertiles. Factors associated with higher versus lower similarity were estimated with multivariable ordinal logistic regression and reported as adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

Of the 225 participants, median age was 25 years (interquartile range, 22-29 years), 62% were living with HIV, median HPVs was 3 (interquartile range, 2-5), and HPV6 (28%), HPV16 (26%), HPV11 (23%), and HPV45 (20%) were most prevalent. Fifty-three percent of participants had highly similar HPVs at 3 months, and the similarity was associated with HIV (aOR, 3.11; 95% CI, 1.6-5.9) and recent receptive sex (aOR, 1.9; 95% CI, 1.0-3.5). By 12 months, 20% had highly similar HPVs, and it was associated with 12 years or longer since anal coital debut (aOR, 6.8; 95% CI, 3.1-5.2), self-reported genital warts (aOR, 3.1; 95% CI, 1.5-6.6), and 200 or less CD4 cells/mm3 (aOR, 13.3; 95% CI, 2.7-65.2) for those living with HIV.

CONCLUSIONS

Studies evaluating the JSI as a predictor of high-grade intraepithelial lesions would further confirm its applicability as a quantitative measure of multiple HPV persistence.

Gene methylation of CADM1 and MAL identified as a biomarker of high grade anal intraepithelial neoplasia

Human papillomavirus (HPV) is detected in up to 96% of anal squamous cell cancers, where screening programs needed. However, the best methodology is still undetermined. Host DNA methylation markers CADM1, MAL and miR124 have been identified in cervical disease, but not anal disease. Anal swabs varying by disease grade were assessed for DNA methylation of CADM1, MAL and miR124-2. Each marker was compared across disease grades, stratified by HPV and HIV status. Receiver operating characteristic curves identified the predictive value of significant gene candidates. CADM1 methylation was significantly higher in high-grade squamous intraepithelial lesions (HSIL) compared with low-grade (LSIL) (p = 0.005) or normal (p < 0.001) samples with 67.2% correctly identified as HSIL. MAL methylation was significantly (p = 0.002) increased in HSIL compared with LSIL in HIV positive participants with 79.8% correctly indicated as HSIL. Gene miR124-2, showed no difference between disease grades. Biomarkers with established diagnostic value in cervical disease have limited utility in the prediction of anal disease, with CADM1 identified as a marker with screening potential in a gay and bisexual men (GBM) population and MAL in HIV positive GBM population. New markers specific to the anal mucosa are required to improve triage of high-risk individuals.

Heterogeneity in the Prevalence of High-Risk Human Papillomavirus Infection in Human Immunodeficiency Virus-Negative and Human Immunodeficiency Virus-Positive Men Who Have Sex With Men in West Africa

BACKGROUND

Men who have sex with men (MSM) are at high risk of human papillomavirus (HPV) infection. We assessed (i) the prevalence of high-risk HPV (HR-HPV) infection and associated factors, and (ii) the prevalence of vaccine-preventable HPV infections in MSM in Burkina Faso, Côte d'Ivoire, Mali, and Togo.

METHODS

A cross-sectional study was conducted in 2017-2018 among MSM ≥18 years old followed in community-based clinics. HPV infection was investigated in oral and anal samples using the e-BRID system. Factors associated with HR-HPV infection were identified using multivariate logistic regressions.

RESULTS

Among 631 participants, 425 were HIV-negative and 206 HIV-positive. HR-HPV prevalence ranged from 9.2% to 34.8% in the former, and 33.3% to 71.0% in the latter, according to the study country. In multivariate analysis, HIV infection (adjusted odds ratio (aOR) 3.61, 95% confidence interval (CI) 2.48-5.27) and study country (4.73, 2.66-8.43 for Mali; 3.12, 1.68-5.80 for Burkina Faso; 3.51, 1.92-6.42 for Togo) were associated with HR-HPV infection. Other associated factors were low educational level, self-defined homosexual identity, and condomless anal sex. The prevalence of infections which can be prevented with bivalent, quadrivalent, and nonavalent vaccines was 5.9, 27.1, and 34.6% in HIV-negative participants, and 18.9, 43.7, and 54.9% in HIV-positive participants, respectively.

CONCLUSIONS

HR-HPV prevalence was very heterogeneous between the study countries in both HIV-negative and HIV-positive MSM. Vaccine-preventable HPV infections predominated. Vaccination should be proposed to young MSM to reduce the burden of HPV infection in this vulnerable population and their female partners in West Africa.

Anal human papillomavirus prevalence and risk factors among men who have sex with men in Vietnam

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HPV infection in men having sex with men (MSM) was studied in two cities of Vietnam

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Prevalence of any HPV and HPV16/18 among MSM was 32.3% and 11.0%, respectively

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High-risk HPV infections in MSM were associated with risky sexual behaviours

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A targeted HPV vaccination strategy would be beneficial for MSM in Vietnam

Objectives

Men who have sex with men (MSM) are at risk of human papillomavirus (HPV)-related cancers, while published data are scarce. This study determined HPV prevalence and risk factors in MSM in Vietnam to inform HPV prevention strategies in this key population.

Methods

A cross-sectional study of 799 MSM aged 16-50 years was conducted in Vietnam in 2017-2018. Information was collected on risk behaviours, and knowledge of HPV and anal cancer; rectal swabs were taken to detect anal HPV infection. An in-house polymerase chain reaction and Genoflow HPV array test kit were used for HPV detection and genotyping.

Results

The median age of the study participants was 25 years (range 18-52). Overall prevalence of any HPV and HPV16/18 infection was 32.3% and 11.0%, respectively. A higher prevalence of high-risk HPV infection to all 14 types tested was found in Ho Chi Minh City (30.9%) than in Hanoi (18.4%). High-risk HPV infection was associated with inconsistent condom use and history of engaging in sex under the influence of drugs (adjusted odds ratio (aOR), 2.27; 95% CI, 1.48-10.67), as well as having multiple sexual partners (aOR, 1.01; 95% CI, 1.00–1.02).

Conclusions

High-risk anal HPV infections in Vietnamese MSM were significantly associated with risky sexual behaviours. A targeted HPV vaccination strategy would have substantial benefit for MSM in Vietnam.

Prevalence of anal cytological abnormalities and high-risk human papillomavirus prevalence in kidney transplant recipients: A cross-sectional study

BACKGROUND

Transplant recipients are at high-risk of anal squamous cell cancer. We aimed to estimate the prevalence of high-risk human papillomavirus (HPV) and high-grade squamous intraepithelial lesion (HSIL) and assess characteristics associated with results METHODS: We recruited kidney transplant recipients in a single-center, 2015-2018. Participants completed a clinical questionnaire and received an anal-swab sent for HPV-DNA and cytological testing RESULTS: A total of 97 (74%) of 125 recipients approached consented to participate. Participants were median 47 (IQR 40-55) years, 60% male and median 4.5 (IQR .9-13) months-since-transplant. Of 86 assessable samples, at least one HPV genotype was detected in 15 (17%) participants; 1 (1%) HPV16, 8 (9%) other high-risk HPV. Of 76 assessable cytology samples, 9 (12%) showed evidence of abnormality; 1 (1%) HSIL, 1 (1%) atypical-squamous-cells, cannot exclude HSIL. Both HSIL recipients had high-risk HPV and biopsy confirmed HSIL. High-risk HPV was detected in six (9%) recipients with normal cytology. History of sexually transmitted infection, and abnormal cervical pap smear in women, was associated with high-risk HPV and HSIL CONCLUSIONS: High-risk HPV and HSIL testing may identify kidney transplant recipients at higher risk of anal cancer. Longitudinal studies are needed to describe the natural history of anal cancer in transplant recipients.

Prevalence of human papillomavirus in young men who have sex with men after the implementation of gender-neutral HPV vaccination: a repeated cross-sectional study

BACKGROUND

Anal infection with high-risk human papillomavirus (HPV) genotypes 16 and 18 and anal cancer are overrepresented in men who have sex with men (MSM). This study investigated HPV prevalence in young MSM before and after the implementation of a school-based quadrivalent HPV (genotypes 6, 11, 16, and 18) vaccination programme for boys in Australia in 2013.

METHODS

In this repeated cross-sectional study, MSM aged 16-20 years were recruited from two successive birth cohorts via sexual health clinics and the community in Melbourne, Australia. The first cohort was before the implementation of gender-neutral vaccination (HYPER1 study, done in 2010-12, NCT01422356), and the second was the post-vaccination cohort (HYPER2 study, done in 2017-18, NCT03000933). Men who self-identified as being same-sex attracted were enrolled, and those recruited via the HYPER2 study had to be resident in Australia since 2013 to ensure eligibility. Study procedures were done in the Melbourne Sexual Health Centre. A clinician-collected anal swab and self-collected penile swab and oral rinse were tested for 28 HPV genotypes, and data on demographics and sexual health practices were collected via questionnaires. Only assessable samples were included in the analyses. We compared anatomical site-specific prevalence of HPV genotypes between cohorts by calculating the prevalence ratio, adjusting for age, circumcision, and sex with women. Herd protection was also assessed, by calculating the adjusted prevalence ratios by vaccination status.

FINDINGS

400 MSM, 200 per cohort, were included in the study. In both cohorts, the median number of lifetime male partners was ten (IQR 5-25). The prevalence of any anal quadrivalent vaccine-preventable HPV genotype was higher in the pre-vaccination cohort (54 [28%] of 193) than in the post-vaccination cohort (14 [7%] of 193; adjusted prevalence ratio [PR] 0·24, 95% CI 0·14-0·42), largely driven by decreases in HPV6, followed by HPV11, 16, and 18. Nevertheless, there was also a significant reduction in anal HPV16 and 18 in the post-vaccination cohort from the pre-vaccination cohort (0·31, 0·14-0·68). The prevalence of any penile quadrivalent vaccine-preventable HPV genotype was also higher in the pre-vaccination cohort (21 [12%] of 177) than in the post-vaccination cohort (11 [6%] of 179; 0·48, 0·24-0·97), driven by decreases in HPV 6 and 11, but not by 16 and 18. The prevalence of any oral quadrivalent vaccine-preventable HPV genotype was higher in the pre-vaccination cohort (seven [4%] of 200) than in the post-vaccination cohort (one [1%] of 199; 0·10, 0·01-0·97); there were no cases of oral HPV6 or 11 detected in HYPER2. Comparing the pre-vaccinated cohort with the 149 confirmed vaccinated men from HYPER2 showed a reduction in any quadrivalent vaccine-preventable HPV genotype for anal (0·09, 0·03-0·25) and penile (0·18, 0·05-0·59) infection but not for oral infection (0·17, 0·03-1·08).

INTERPRETATION

A reduction in anal, penile, and oral quadrivalent vaccine-targeted genotypes occurred in young MSM following the implementation of a school-based gender-neutral HPV vaccination programme. The fall in anal HPV16 and 18 may lead to a reduction in the incidence of anal cancer.

FUNDING

Merck and the Australian Government Department of Health.

Human Papillomavirus Genotypes in Anal High-Grade Squamous Intraepithelial Lesion (HSIL): Anal Intraepithelial Neoplasia Grades 2 (AIN2) and 3 (AIN3) Are Different

BACKGROUND

Anal high-grade squamous intraepithelial lesion (HSIL) can be histomorphologically categorized into anal intraepithelial neoplasia (AIN) grade 2 (AIN2) and grade 3 (AIN3). Different risk factors for these two categories have been described. We investigated whether there were also differences in lesion-specific human papillomavirus (HPV) genotypes.

METHODS

The Study of the Prevention of Anal Cancer (SPANC) recruited 617 gay and bisexual men (GBM); 36% of participants were HIV positive. At baseline, 196 men (31.8%) had histologic HSIL lesions. Tissue was available for genotyping in 171, with a total of 239 HSIL lesions (183 AIN3 and 56 AIN2). Using laser capture microdissection, each lesion revealed a maximum of one genotype.

RESULTS

High-risk HPV (HR-HPV) genotypes were found in 220 (92.1%) HSIL lesions, with no significant difference between AIN3 (93.4%) and AIN2 (87.5%). AIN3 lesions had significantly more HPV16 (42.1%) than AIN2 lesions (12.5%; P < 0.001) and AIN2 lesions had significantly more non-16 HR-HPV types (75.0%) than AIN3 lesions (51.4%; P = 0.002). These associations were similar for HIV-negative men with HPV16 in 51.1% AIN3 and 18.2% AIN2 (P = 0.001) and non-16 HR-HPV in 40.0% AIN3 and 75.8% AIN2 (P < 0.001). For HIV-positive men, HPV16 remained more frequently detected in AIN3 (33.3% vs. 4.4% for AIN2; P = 0.004), but there was no difference between AIN3 and AIN2 for non-16 HR-HPV (62.4% vs. 73.9%; P = 0.300).

CONCLUSIONS

As HPV16 has the strongest link with anal cancer, the subcategorization of HSIL may enable stratification of lesions for anal cancer risk and guide anal HSIL management.

IMPACT

Stratification of anal cancer risk by histologic HSIL grade.

Distribution of HPV Genotypes in Patients with a Diagnosis of Anal Cancer in an Italian Region

Objectives: Anal cancer is a rare disease. However, its incidence is increasing in some population groups. Infection caused by Human Papillomavirus (HPV) is strongly associated with the risk of anal cancer, whose variability depends on samples, histology, and HPV detection methods. The aim of the study was to assess prevalence and distribution of HPV genotypes in patients diagnosed with anal carcinoma. Methods: An observational, retrospective study was carried out in a tertiary care hospital in North Sardinia, Italy. Specimens of anal cancer diagnosed from 2002–2018 were selected. Demographic, epidemiological, and clinical variables were collected to assess their relationship with the occurrence of anal cancer. Results: The overall HPV positivity was 70.0% (21/30), with HPV-16 being the predominant genotype (~85%). The highest prevalence of anal cancer was in patients aged ≥55 years. HPV positivity was higher in women (p-value > 0.05) and in moderately differentiated samples (G2) (p-value < 0.05). p16^INK4a and E6-transcript positivity were found in 57% and 24% of the HPV positive samples, respectively. The OS (overall survival) showed a not statistically significant difference in prognosis between HPV positive sand negatives (10, 47.6%, vs. 4, 44.4%; p-value = 0.25). Conclusions: HPV-DNA and p16^INK4a positivity confirmed the role of HPV in anal carcinoma. Our findings could support the implementation and scale-up of HPV vaccination in males and females to decrease the incidence of HPV-associated cancers. Further studies are needed to better clarify the prognostic role of HPV/p16 status.

Multiple HPV infections among men who have sex with men engaged in anal cancer screening in Abuja, Nigeria

Background

Anal precancers and cancers can be detected during screening with high-resolution anoscopy (HRA). The sensitivity of HRA depends on the burden and duration of human papillomavirus (HPV) among those screened as well as anoscopist proficiency, which is highly correlated with prior screening experience. Our objective was to compare the identification and type of HPV and the likelihood of HRA-detected precancer for men who have sex with men (MSM) undergoing their first HRA-screening in Nigeria.

Methods

MSM were recruited from an HIV test-and-treat cohort, TRUST/RV368, into a new anal cancer screening program. Anal swabs obtained during screening underwent Ion Torrent next-generation sequencing using barcoded HPV PCR broad-spectrum primers 5+/6+ to detect up to 161 HPVs. All high-risk (HR) HPVs and the most abundant low-risk (LR)-HPVs were evaluated as type-specific infections with some categorized as belonging to a multiple infection. HRA screening results included benign, low-grade squamous intraepithelial lesions (LSIL), or HSIL as detected by cytology or histology. Multivariable logistic regression was used to assess the association of HPV and other cofactors with any SIL.

Results

Among 342 MSM, 60% were HIV-infected, 89% were under 35 years of age, and 51% had 8 or more years since anal coital debut. Of those with SIL, 89% had LSIL and only 11% had HSIL. Prevalence of any HPV and high-risk (HR)-HPV was 92% and 74%, respectively. The most prevalent genotypes in rank order were HPV6 (31%), HPV16 (23%), HPV42 (20%), HPV11 (18%), HPV45 (18%), and HPV51 (17%). For multiple HR-HPVs, 31% had a single HR-HPV, 32% had 2-3, and 10% had 4 or more. Low-risk HPVs, type 6 and/or 11, were common (42%) and were significantly associated with SIL (adjusted odds ratio [aOR]:1.8, 95% confidence interval [CI]: 1.1–3.1) together with perianal warts (aOR:6.7, 95% CI: 3.3–13.5). In contrast, HR-HPV and multiple HR-HPVs were not significantly associated with SIL (all p > 0.05).

Conclusions

Detection of HSIL was low. Although HR-HPV was abundant, HSIL development also depends on the duration of HR-HPV infections and the anoscopist's level of experience. As our cohort ages and the anoscopist becomes more skilled, detection of HSIL will likely improve.

Scientific evidence supporting recommendations on the use of the 9-valent HPV vaccine in a 2-dose vaccine schedule in Australia

The Australian Technical Advisory Group on Immunisation (ATAGI) updated recommendations on the use of human papillomavirus (HPV) vaccines in the Australian Immunisation Handbook in 2018, regarding the use of the recently available 9-valent (9vHPV) vaccine, Gardasil 9, and a 2-dose schedule for young adolescents for HPV vaccines. This report provides an overview of the relevant scientific evidence that underpinned these updated recommendations. The 9vHPV vaccine includes 5 HPV types (HPV 31, 33, 45, 52 and 58) additional to the 4 that are also covered by the 4vHPV (Gardasil) vaccine (HPV 6,11,16,18). Accordingly, the 9vHPV vaccine is expected to prevent an additional 15% of cervical cancers and up to 20% of other HPV-related cancers. Non-inferior antibody responses after two 9vHPV vaccine doses given 6-12 months apart in girls and boys aged 9-14 years compared to women aged 16-26 years after three doses support the 2-dose schedule for adolescents of this age group. In clinical trials 9vHPV vaccine was well-tolerated with a similar safety profile to 4vHPV vaccine. The switch to 9vHPV vaccine and a 2-dose schedule is anticipated to improve public acceptability of the program and reduce HPV-related disease in the long-term.

Prevalence and associations of larger burden of intra-anal high-grade squamous intraepithelial lesions at baseline in an Australian cohort of gay and bisexual men: The Study of the Prevention of Anal Cancer

OBJECTIVES

To investigate factors associated with larger burden of intra-anal high-grade squamous intraepithelial lesions (HSIL) in a natural history study of HSIL.

METHODS

617 gay and bisexual men (GBM) attended a baseline visit. High-resolution anoscopy-directed biopsy was performed of suspected HSIL. GBM with biopsy-confirmed HSIL (bHSIL) affecting a single-octant were compared with those who had bHSIL affecting a larger area.

RESULTS

Of 196 men with bHSIL at baseline, 73 (37.2 %) had larger bHSIL burden. Larger burden was independently associated with anal HPV16 detection (aOR 2.06, 95 % CI 1.09-3.89, p = 0.026) and infection with a greater number of high-risk HPV types (aOR per type increase 1.25, 95 % CI 1.05-1.49, p-trend = 0.010).

CONCLUSION

The observation that men with a larger burden of HSIL also had more risk factors for anal cancer suggests this group may warrant closer observation to ensure earlier detection, and thus improved prognosis, of individuals whose HSIL may progress to anal cancer.

The impact of 10 years of human papillomavirus (HPV) vaccination in Australia: what additional disease burden will a nonavalent vaccine prevent?

Background: A National human papilloma virus (HPV) Vaccination Programme for the prevention of HPV infection and associated disease using the quadrivalent HPV vaccine (4vHPV) has been funded and implemented in Australia since 2007, initially for girls only and extended to boys in 2013, with uptake rates among the highest observed worldwide. Aim: We report on the impact of this national programme on HPV prevalence and associated disease burden and estimate the potential impact of adopting a nonavalent HPV (9vHPV) vaccine. Methods: We performed a non-systematic literature review of studies measuring the burden of HPV-associated disease and infection in Australia before and after introduction of HPV vaccination. We also included key national reports with estimates of HPV-related disease burden. Results: Substantial declines in high-grade cervical disease and genital warts among vaccine-eligible women have been observed. Reductions in genital warts incidence and HPV prevalence among heterosexual men of similar age were observed before introduction of the male vaccination programme, indicating a substantial herd effect. 9vHPV vaccine is expected to prevent up to 90% of cervical and 96% of anal cancers. Of an estimated 1,544 HPV-associated cancers in 2012, 1,242 would have been preventable by the 4vHPV vaccine and an additional 187 anogenital cancers by the 9vHPV vaccine. Conclusions: Vaccination using 4vHPV vaccine has had a large demonstrable impact on HPV-related disease in Australia. A switch to 9vHPV could further reduce the HPV-associated cancer burden. With continued high coverage among both males and females, elimination of vaccine-type HPV disease seems achievable in Australia.

Human Papillomavirus and Anal Cancer: Prevalence, Genotype Distribution, and Prognosis Aspects from Midwestern Region of Brazil

BACKGROUND

Approximately 90% of all anal cancers are associated with human papillomavirus (HPV), especially high-risk genotypes such as HPVs 16 and 18.

OBJECTIVE

To investigate the clinical and prognostic aspects of anal cancers associated with the presence, as well as the genotypic distribution of human papillomavirus (HPV).

METHODS

A retrospective study carried out over a 10-year period, using clinical and molecular data, with PCR analysis and reverse hybridization (INNO-LIPA kit), in anal cancers. The data analysis was done using descriptive univariate statistics, and the survival curves were made using the Kaplan-Meier and log-rank methods.

RESULTS

Of the 81 formalin-fixed and paraffin-embedded specimens, HPV prevalence was 69% and was significantly higher in squamous cell carcinomas (SCC) than in other anal tumors (p=0.0001). Female patients had a higher prevalence of HPV (p=0.01). Multiple infections were detected in 14.3% of cases. The most prevalent genotypes were HPVs 16, 33, and 18. The overall survival at 60 months was 44.3%, and the prognostic factors included gender (p=0.008) with greater survival for men (52.9%) in comparison to women (29.6%), histological type (p=0.01), SCC (54.4%), adenocarcinomas (37.5%), other carcinomas (14.2%), and the presence of distant metastasis (p=0.01). Survival was not influenced by the presence of HPV (p=0.54).

CONCLUSIONS

The association of HPV to anal cancer was found in this study, especially in SCC. However, the presence of HPV did not influence the prognosis of patients with anal cancer.

New Insights into the Role of Human Papillomavirus in Anal Cancer and Anal Wart Development

Human papillomavirus is associated with several anogenital and oropharyngeal lesions, including warts, premalignant lesions, and cancer. There are specific groups that were identified as high-risk groups for anal squamous cell carcinoma and anal human papillomavirus infection, namely HIV-positive patients, men who have sex with men, women with genital tract neoplasia, and solid organ transplant recipients. Condylomas have classically been considered to be a benign lesion, with an exception made for the Buschke-Loewenstein tumor, but several publications have shown that a high percentage of condylomas harbor high-grade lesions. Due to the similarities between anal and cervical carcinogenesis, anal cancer screening based on anal cytology and referral to high-resolution anoscopy, in case of abnormalities, have been advocated. Testing for anal human papillomavirus is not routinely done in anal cancer screening, because of the very high prevalence in high-risk populations. The large majority of anal cancers are squamous cell carcinomas (SCC), and around 90% are attributed to human papillomavirus. Human papillomavirus positivity in anal SCC seems to have a prognostic value, with better survival in those patients with positive tumors. Prophylactic vaccination has been shown to be important for prevention of anal human papillomavirus-related lesions.

Histological outcomes of anal high-grade cytopredictions

BACKGROUND

Longitudinal studies of histological outcomes after anal cytological screening in men who have sex with men (MSM) are rare. This study measured the positive predictive values (PPVs) of each level of baseline cytological abnormality in MSM in Sydney, Australia, over a 12-month period.

METHODS

The Study of the Prevention of Anal Cancer is a 3-year prospective study of the natural history of anal human papillomavirus infection in MSM at least 35 years old. For each participant with a baseline cytological abnormality, the worst histology was recorded at the baseline high-resolution anoscopy and at 6 and 12 months. PPVs for a histological high-grade squamous intraepithelial lesion (HSIL) diagnosis were calculated for each level of baseline cytological abnormality at each time point.

RESULTS

Among 424 men who completed 3 visits, the PPV of a cytological HSIL increased from 71.6% at the baseline to 86.4% at 6 months and to 92.6% at 12 months (P < .001). For cytological atypical squamous cells, cannot rule out high-grade squamous intraepithelial lesion (ASC-H), the PPV increased from 51.5% at the baseline to 69.7% at 6 months and to 75.8% at 12 months (P = .004). At each time point, the PPV of a cytological HSIL was significantly higher than the PPV of ASC-H. The PPV of low-grade cytology reports was significantly lower than the PPV of ASC-H at each time point.

CONCLUSIONS

In a cohort of MSM, a baseline histological HSIL diagnosis after an HSIL cytoprediction is high, and it increases with further examinations over the course of 12 months. Lower levels of cytological abnormalities have significantly lower PPVs. These data can inform patient management and the quality assessment of each aspect of the screening pathway. Cancer Cytopathol 2018;126:136-44. © 2017 American Cancer Society.

Human papillomavirus antibody response following HAART initiation among MSM

OBJECTIVE

To describe effects of HAART on high-risk human papillomavirus (HPV) antibody response in HIV-positive MSM and the meaning of this response for subsequent HPV-related cancer risk.

DESIGN

Prospective seroepidemiological study of 281 HIV-positive MSM initiating HAART between 1995 and 2004 in the Swiss HIV Cohort Study.

METHODS

For each individual, two serum samples, one at HAART initiation (pre-HAART) and another 24 months later (post-HAART), were tested for L1 antibodies to HPV6, 11, 16, 18, 31, 33, 35, 45, 52 and 58, as well as HPV16-E6 antibodies, using a multiplex serology assay. Identification of HPV-related cancer included data linkage with Swiss cancer registries.

RESULTS

Pre-HAART, 45.2% were seropositive for any high-risk HPV-L1 and 32.4% for HPV16-L1. Sexual intercourse during the last 6 months was the only evaluated factor associated with L1 seropositivity pre-HAART. Seropositivity increased post-HAART to 60.5% for any high-risk HPV-L1 [prevalence ratio versus pre-HAART = 1.34, 95% confidence interval (CI) 1.14-1.57] and 48.0% for HPV16-L1 (prevalence ratio versus pre-HAART = 1.48, 95% CI 1.20-1.83), and seroconversion was significantly associated with both lower CD4 cell count and CD4/CD8 ratio (P < 0.01). Only one individual was HPV16-E6-seropositive pre-HAART, but two more seroconverted post-HAART. Anal cancer incidence among the three HPV16-E6-positives post-HAART was significantly increased compared with HPV16-E6-negatives (incidence rate ratio = 63.1, 95% CI 1.1-1211).

CONCLUSION

HAART-related immune reconstitution increases HPV-specific antibody responses, which may discriminate future anal cancer risk in this high-risk population.

Cancers in Australia in 2010 attributable to infectious agents

OBJECTIVES

To estimate the proportion and numbers of cancers in Australia in 2010 attributable to infectious agents.

METHODS

The population attributable fraction (PAF) and number of cancers caused by hepatitis B and C viruses (HBV, HCV), Helicobacter pylori and human immunodeficiency virus (HIV) were calculated using standard formulae incorporating prevalence of infection in the Australian population, the relative risks associated with that infection and cancer incidence. For cancers with very strong associations to the infectious agent (Epstein-Barr virus [EBV], human papillomavirus [HPV] and HIV/Kaposi's sarcoma herpes virus [KSHV]), calculations were based on viral prevalence in the tumour.

RESULTS

An estimated 3,421 cancers (2.9% of all cancers) in Australia in 2010 were attributable to infections. Infectious agents causing the largest numbers of cancers were HPV (n=1,706), H. pylori (n=793) and HBV/HCV (n=518). Cancer sites with the greatest number of cancers caused by infections were cervix (n=818), stomach (n=694) and liver (n=483). Cancers with highest proportions attributable to infectious agents were Kaposi's sarcoma (100%), cervix (100%), nasopharynx (87%), anus (84%) and vagina (70%).

CONCLUSIONS

Infectious agents cause more than 3,000 cancers annually in Australia.

IMPLICATIONS

Opportunities for cancer prevention through infection control are considerable, even in a 'first world' nation like Australia.

A Composite Cytology-Histology Endpoint Allows a More Accurate Estimate of Anal High-Grade Squamous Intraepithelial Lesion Prevalence

BACKGROUND

There is debate about the accuracy of anal cytology and high-resolution anoscopy (HRA), in the diagnosis of anal human papillomavirus (HPV)-related squamous intraepithelial lesions (SIL). Few studies have performed both simultaneously in a large sample of high-risk individuals.

METHODS

At baseline in a community-based cohort of HIV-infected and uninfected homosexual men ages ≥35 years in Sydney, Australia, all men underwent anal swabbing for cytology and HPV genotyping, and HRA-guided biopsy. We evaluated the separate and combined diagnostic accuracy of cytology and histology, based on a comparison with the prevalence of HPV16 and other high-risk (HR) HPV. We examined trends in HPV prevalence across cytology-histology combinations.

RESULTS

Anal swab, HRA, and HPV genotyping results were available for 605 of 617 participants. The prevalence of cytologically predicted high-grade SIL (HSIL, 17.9%) was lower than histologically diagnosed HSIL (31.7%, P < 0.001). The prevalence of composite-HSIL (detected by either method) was 37.7%. HPV16 prevalence was similar in men with HSIL by cytology (59.3%), HSIL by histology (51.0%), and composite-HSIL (50.0%). HPV16 prevalence was 31.1% in men with composite-atypical squamous cells suggestive of HSIL, to 18.5% in men with composite-low-grade SIL, to 12.1% in men with composite-negative results (Ptrend < 0.001).

CONCLUSIONS

Significantly more HSIL was detected when a composite cytology-histology endpoint was used. Increasing grade of composite endpoint was associated with increasing HPV16 prevalence.

IMPACT

These data suggest that a composite cytology-histology endpoint reflects meaningful disease categories and is likely to be an important biomarker in anal cancer prevention. Cancer Epidemiol Biomarkers Prev; 25(7); 1134-43. ©2016 AACR.

[HPV-induced anal lesions]

Human papillomavirus (HPV) infections belong to the most common sexually transmitted infections. To date, more than 200 completely classified HPV-types have been reported, and those belonging to the genus alpha predominantly infect the anogenital region. Condylomata acuminata are caused by the two low-risk types HPV6 and HPV11 in more than 90 % of cases. Treatment of genital warts might be either ablative (e.g. electrocautery, surgical excision, or laser therapy) or topical (e.g. podophyllotoxine, trichloroacetic acid, or imiquimod), and depends on the size, location, morphology and anatomical region. Recurrences after treatment are frequent. Therefore, combination therapies (e.g. topical and ablative) play an important role in daily routine. HIV-infected individuals, especially HIV-positive MSM, have a strongly increased risk for anal dysplasia and anal cancer. Condylomata acuminata and a large proportion of anal dysplasia and anal carcinoma are preventable by prophylactic HPV-vaccination.

Prophylactic HPV vaccination and anal cancer

The incidence of anal cancer is increasing. High risk populations include HIV-positive men who have sex with men (MSM), HIV-negative MSM, HIV-positive women and heterosexual men and women with a history of cervical cancer. HPV has been detected in over 90% of anal cancers. HPV16 is the most common genotype detected in about 70% of anal cancers. The quadrivalent HPV (qHPV) vaccine has been demonstrated to prevent vaccine associated persistent anal HPV infections as well as anal intraepithelial neoplasia grades 2-3 (AIN2+) in young MSM not previously infected. A retrospective analysis also suggests that qHPV vaccination of older MSM treated for AIN2+ may significantly decrease the risk of recurrence of the AIN2+. The HPV types detected in anal cancer are included in the 9-valent vaccine. Thus, the 9-valent HPV vaccine, when administered to boys and girls prior to the onset of sexual activity, should effectively prevent anal cancer.

Anal cancer and intraepithelial neoplasia screening: A review

This review focuses on the early diagnosis of anal cancer and its precursor lesions through routine screening. A number of risk-stratification strategies as well as screening techniques have been suggested, and currently little consensus exists among national societies. Much of the current clinical rationale for the prevention of anal cancer derives from the similar tumor biology of cervical cancer and the successful use of routine screening to identify cervical cancer and its precursors early in the disease process. It is thought that such a strategy of identifying early anal intraepithelial neoplasia will reduce the incidence of invasive anal cancer. The low prevalence of anal cancer in the general population prevents the use of routine screening. However, routine screening of selected populations has been shown to be a more promising strategy. Potential screening modalities include digital anorectal exam, anal Papanicolaou testing, human papilloma virus co-testing, and high-resolution anoscopy. Additional research associating high-grade dysplasia treatment with anal cancer prevention as well as direct comparisons of screening regimens is necessary to develop further anal cancer screening recommendations.

Trends in incidence and survival for anal cancer in New South Wales, Australia, 1972-2009

INTRODUCTION

Little is known about the incidence and survival of anal cancer in New South Wales (NSW), Australia, as anal cancer cases are often grouped together with other colorectal cancers in descriptive epidemiological analyses.

METHODS

We studied patterns and trends in the incidence and survival of people diagnosed with anal cancer in NSW, Australia, 1972-2009 (n=2724). We also predicted anal cancer incidence in NSW during 2010-2032. Given the human papilloma virus-associated aetiology for most anal cancers, we quantified these changes over time in incidence and survival by histological subtype: anal squamous cell carcinoma (ASCC); and anal adenocarcinoma (AAC).

RESULTS

There was a linear increase in incident anal cancer cases in NSW with an average annual percentage change (AAPC) of 1.6 (95% CI 1.1-2.0) such that, in combination with age-period-cohort modelling, we predict there will be 198 cases of anal cancer in the 2032 calendar year (95% CI 169-236). Almost all of these anal cancer cases are projected to be ASCC (94%). Survival improved over time regardless of histological subtype. However, five-year relative survival was substantially higher for people with ASCC (70% (95% CI 66-74%)) compared to AAC (51% (95% CI 43-59%)), a 37% difference. Survival was also greater for women (69% (95% CI 64-73%)) with ASCC compared to men (55% (95% CI 50-60%)). It was not possible to estimate survival by stage at diagnosis particularly given that 8% of all cases were recorded as having distant stage and 22% had missing stage data.

INTERPRETATION

Aetiological explanations, namely exposure to oncogenic types of human papillomavirus, along with demographic changes most likely explain the actual and projected increase in ASCC case numbers. Survival differences by gender and histological subtype point to areas where further research is warranted to improve treatment and outcomes for all anal cancer patients.

Laser capture microdissection as a tool to evaluate human papillomavirus genotyping and methylation as biomarkers of persistence and progression of anal lesions

INTRODUCTION

Anal squamous cell carcinoma is preceded by persistent infection with high-risk human papillomavirus (HPV) and the cancer precursor, high-grade squamous intraepithelial lesion (HSIL). Detection of specific HPV genotypes and HPV-related biomarkers may be an option for primary anal screening. However, more data on the natural history of HPV-related anal lesions are required. The outcomes from this study will enhance our understanding of the clinical and biological behaviour of HPV-related anal lesions and inform the development of future HPV genotype and/or biomarker screening tests.

METHODS AND ANALYSIS

HIV-negative and HIV-positive men who have sex with men, aged 35 years and over, recruited from community-based settings in Sydney, Australia, attend 6 clinic visits over 3 years. At the first 5 visits, participants undergo a digital anorectal examination, an anal swab for HPV genotyping and anal cytology, and high-resolution anoscopy with directed biopsy of any visible abnormalities that are suggestive of any abnormality suspicious of SIL. Tissue sections from participants diagnosed with histologically confirmed HSIL at the baseline clinic visit will undergo laser capture microdissection, HPV detection and genotyping, and quantitation of CpG methylation in baseline and follow-up biopsies. Histological and cytological findings in combination with HPV genotyping data will be used to identify persistent HSIL. HSIL will be stratified as non-persistent and persistent based on their status at 12 months. The performance of HPV genotype and methylation status in predicting disease persistence at 12 months will be assessed, along with associations with HIV status and other covariates such as age.

ETHICS AND DISSEMINATION

The St Vincent's Hospital Ethics Committee granted ethics approval for the study. Written informed consent is obtained from all individuals before any study-specific procedures are performed. Findings from this study will be disseminated to participants and the community through study newsletters, and through peer-reviewed publications and international conferences.

Human papillomavirus status, anal cytology and histopathological outcome in HIV-positive patients

BACKGROUND

Human papillomavirus (HPV) are responsible for a broad spectrum of mucocutaneous infections and may cause squamous cell carcinoma following long-standing infection . Oncogenic HPV, most commonly HPV 16, are detectable in over 90% of cervical intraepithelial neoplasia and anal intraepithelial neoplasia (AIN). Human immunodeficiency virus (HIV) infection is strongly associated with a higher prevalence of chronic HPV infection, a higher incidence of AIN and an increased risk for anal cancer (AC). In September 2013, guidelines concerning prevention, screening and treatment of AIN for patients affected by HIV were issued by the German AIDS society.

OBJECTIVE

In order to validate the suggested screening procedure, we analysed data from 123 male and female patients with HIV infection that regularly present in our outpatient clinic.

METHODS

Anal cytology, HPV typing and high-resolution anoscopy (HRA) were performed.

RESULTS

Our results show that screening by anal cytology only identifies a minority of patients with high grade AIN (AIN 3) histology. Patients with normal cytology (NILM, cytology graded negative for intraepithelial lesion or malignancy; n = 5, 29.4%), atypical squamous cells of undetermined significance (ASCUS; n = 5, 71.4%) and low grade squamous intraepithelial lesion (LSIL; n = 8, 44.5%) showed highly dysplastic lesions (AIN 2 and 3) in the histological workup more frequently than expected. Additionally, high-grade squamous intraepithelial lesion (HSIL) was strongly associated with detection of high-risk oncogenic HPV.

CONCLUSION

Anal cytology as the solitary screening tool for anal cancer fails to detect anal dysplasia in a considerable number of patients. Additionally, HPV typing and possibly further biomarkers might be applied to identify those patients with a higher risk of developing anal carcinoma, in order to monitor them more closely or directly transfer them to HRA.