Sequential Acquisition of Anal Human Papillomavirus (HPV) Infection Following Genital Infection Among Men Who Have Sex With Women: The HPV Infection in Men (HIM) Study

Sexual risk characteristics, social vulnerability, and anal cancer screening uptake among men living with HIV in the deep south

ABSTRACTWithout standard guidelines, there is a critical need to examine anal cancer screening uptake in the South which has the highest HIV incidence in the U.S. We identified factors associated with screening among men living with HIV (MLHIV) at a large academic HIV outpatient clinic in Alabama. Relationships between sociodemographic, clinical, sexual risk characteristics and screening were examined using T-tests, Fisher's exact, Chi-square, and logistic regression analyses. Unadjusted and adjusted odds ratios (AOR) were computed to estimate the odds of screening. Among 1,114 men, 52% had received annual anal cytology (pap) screening. Men who were screened were more likely to have multiple sexual partners compared to men who were not screened (22.8% vs. 14.8%, p = 0.002). Among men with one partner, the youngest were almost five times more likely to be screened compared to middle-aged men (AOR = 4.93, 95% CI: 2.34-10.39). Heterosexual men had lower odds and men who reported unprotected anal sex had higher odds of screening. Our findings suggest a racial disparity, with older black MLHIV being the least likely to be screened. In the South, MLHIV who are older, black, heterosexual, or live in high social vulnerability counties may be less likely to receive annual anal cancer screening.

Natural History of Anal HPV Infection in Women Treated for Cervical Intraepithelial Neoplasia

Women with high-grade squamous intraepithelial lesions/cervical intraepithelial neoplasia (HSIL/CIN) are at high risk of anal human papillomavirus HPV infection, and it has also been suggested that self-inoculation of the virus from the anal canal to the cervix could explain HPV recurrence in the cervix after treatment of HSIL/CIN. We aimed to evaluate the bidirectional interactions of HPV infection between these two anatomical sites. We evaluated 68 immunocompetent women undergoing excisional treatment for HSIL/CIN. Immediately before treatment, samples from the anus and the cervix were obtained (baseline anal and cervical HPV status). Cervical HPV clearance after treatment was defined as treatment success. The first follow-up control was scheduled 4-6 months after treatment for cervical and anal samples. High resolution anoscopy (HRA) was performed on patients with persistent anal HPV infections or abnormal anal cytology in the first control. Baseline anal HPV was positive in 42/68 (61.8%) of the women. Anal HPV infection persisted after treatment in 29/68 (42.6%) of the women. One-third of these women (10/29; 34.5%) had HSIL/anal intraepithelial neoplasia (AIN). Among women achieving treatment success, cervical HPV in the first control was positive in 34.6% and 17.6% of the patients with positive and negative baseline anal HPV infection, respectively (p = 0.306). In conclusion, patients with persisting anal HPV after HSIL/CIN treatment are at high risk of HSIL/AIN, suggesting that these women would benefit from anal exploration. The study also suggests that women with anal HPV infection treated for HSIL/CIN might be at higher risk of recurrent cervical HPV even after successful treatment.

Incidence and Clearance of Anal Human Papillomavirus Infection in 16 164 Individuals, According to Human Immunodeficiency Virus Status, Sex, and Male Sexuality: An International Pooled Analysis of 34 Longitudinal Studies

BACKGROUND

Understanding the natural history of anal high-risk human papillomavirus (hrHPV) infection is key for designing anal cancer prevention programs but has not been systematically characterized.

METHODS

We reanalyzed data from 34 studies including 16 164 individuals in 6 risk groups defined by human immunodeficiency virus (HIV) status, sex, and male sexuality: men who have sex with men (MSM) and people with HIV (MSMWH), HIV-negative MSM, women with HIV (WWH), HIV-negative women, men who have sex with women (MSW) with HIV (MSWWH), and HIV-negative MSW. We used Markov models to estimate incidence and clearance of 13 hrHPV types and their determinants.

RESULTS

Human papillomavirus (HPV) 16 had the highest incidence-clearance ratio of the hrHPV types. MSMWH had the highest hrHPV incidence (eg, 15.5% newly HPV-16 infected within 2 years), followed by HIV-negative MSM (7.5%), WWH (6.6%), HIV-negative women (2.9%), MSWWH (1.7%), and HIV-negative MSW (0.7%). Determinants of HPV-16 incidence included HIV status and number of sexual partners for MSM, women, and MSW, and anal sex behavior for MSM only. HPV-16 clearance was lower for people with HIV (PWH) and lower for prevalent than incident infection. Among MSM, increasing age was associated with lower clearance of prevalent, but not incident, HPV-16 infection.

CONCLUSIONS

This robust and unifying analysis of anal hrHPV natural history is essential to designing and predicting the impact of HPV vaccination and HPV-based screening programs on anal cancer prevention, particularly in MSM and PWH. Importantly, it demonstrates the higher carcinogenic potential of longstanding anal prevalent hrHPV infection than more recent incident infection.

Human papillomavirus in men

OBJECTIVE

To describe the clinical behavior of human papillomavirus in men.

MATERIALS AND METHODS

Current international literature was reviewed to describe the clinical behavior of human papillomavirus in men.

RESULTS

Internationally, the overall prevalence of HPV DNA is 50.8%, HPV considered high risk are 14 types. Prevalence of HPV DNA in invasive penile cancer ranges from 33.1% to 47%. HPV-16 has been the most frequent (68.3%), followed by HPV-6 (8.1%) and HPV-18 (6.9%). Positive HPV is described as an independent prognostic factor for cancer-specific survival.

CONCLUSION

It is not clear why HPV infection has a predilection in specific areas of the genital tract. However, it is important to note that there are factors that increase the risk of HPV infection.

Anal Human Papillomavirus Infection in Kidney Transplant Recipients Compared With Immunocompetent Controls

BACKGROUND

Kidney transplant recipients (KTRs) have increased risk of human papillomavirus (HPV)-related anogenital (pre)cancers, including anal high-grade intraepithelial lesions and cancer. Previous studies on anal high-risk HPV (hrHPV) among KTRs are sparse.

METHODS

In a cross-sectional study, we included 247 KTRs and 248 controls from a dermatology department and 5 nephrology departments in Denmark during 2016-2017. All participants provided an anal cytobrush sample that was tested for HPV DNA. Participants completed a questionnaire on lifestyle and sexual habits. We used logistic regression to estimate odds ratios (ORs) of anal hrHPV in KTRs compared with controls and risk factors for anal hrHPV in KTRs.

RESULTS

The anal hrHPV prevalence was higher in female KTRs (45.5%) than in controls (27.2%). Female KTRs had almost 3-fold higher adjusted odds of anal hrHPV than controls (adjusted OR, 2.87 [95% confidence interval, 1.57-5.22]). In contrast, among men we did not observe increased prevalence or odds of anal hrHPV in KTRs compared with controls (prevalence, 19.4% vs 23.6%; adjusted OR, 0.85 [95% 95% confidence interval, .44-1.64]). Among hrHPV-positive KTRs, 63% and 52% of men and women, respectively, were infected with hrHPV types covered by the nonavalent HPV vaccine (type 16, 18, 31, 33, 45, 52, or 58). Current smoking, >10 lifetime sexual partners, history of genital warts, and among men having had receptive anal sex were risk factors for anal hrHPV in KTRs.

CONCLUSIONS

Female KTRs had an increased risk of anal hrHPV compared with immunocompetent controls. Our findings indicate that pretransplant HPV vaccination should be considered to prevent anal high-grade intraepithelial lesions and cancer caused by anal hrHPV infection in KTRs.

CLINICAL TRIALS REGISTRATION

NCT03018327.

Cervical, oral and anal Human papillomavirus infection in women attending the Dermatology Unit of a regional reference hospital in Genoa, Italy: a prevalence study

Human papillomavirus (HPV) infection is the most common sexually transmitted infection (STI) worldwide. In women with genital infection, the virus can be transmitted by sex to the oral cavity of their partners and then to their own oral cavity. The aim of the present study was to establish the prevalence of cervical/anal/oral HPV infection in women attending the Dermatology Unit of the Policlinico San Martino of Genoa, the regional reference hospital in Liguria, Italy.

METHODS

Between January 2016 and December 2018, the female patients attending the STI center (cases) and those requiring a full body skin examination for skin cancer screening ("supposed" healthy population: controls) were recruited. Cervical/anal/oral samples were collected with ThinPrep liquid based cytology preparation system: polymerase chain reaction for HPV and cytological evaluation were performed. Overall, 85 cases and 31 controls were recruited.

RESULTS

Cervical HPV infection was detected in 60% of the cases and 48% of the controls; anal HPV infection in 44% of the cases and 26% of the controls. Cervical and anal HPV infection resulted associated, especially in the control group. Moreover, 32% of the cases and 29% of the controls proved HPV positive in the oral cavity. In the cases of our series, prevalence of cervical, anal and oral HPV infection was higher compared with the controls.

CONCLUSIONS

The high prevalence of anal-oral infections and the frequent association between anal and cervical infections, provide reason to suggest HPV screening also in the anal and oral regions, which may represent HPV reservoirs and grounds for cancer development.

The Association between Smoking and Anal Human Papillomavirus in the HPV Infection in Men Study

BACKGROUND

Previous studies show an association between smoking and anal cancer. The objective of this study was to assess the association between smoking and anal HPV (human papillomavirus) prevalence, incidence, and persistence in men.

METHODS

The HPV Infection in Men (HIM) Study is a multinational study that enrolled HIV-negative men. At baseline and follow-up visits, anal specimens were collected. HPV genotyping was assessed by linear array. Prevalence ratios (PR) were used to assess the association between smoking and anal HPV prevalence. Odds ratios (OR) were used to assess the association between smoking and anal HPV incidence and ≥12-months persistence.

RESULTS

Current smokers have a higher prevalence [adjusted PR (aPR), 1.36; 95% confidence interval (CI), 1.06-1.73) and incidence [adjusted OR (aOR), 1.74; 95% CI, 1.26-2.39] and ≥12-months persistence (aOR, 1.67; 95% CI, 1.19-2.33) of any anal HPV compared with never smokers. There were no differences in the prevalence, incidence, or persistence of anal HPV between former and never smokers. Smoking status was not associated with the prevalence or persistence of anal HPV among men who have sex with men but was associated with higher incidence of HR-HPV. Among men that have sex with women (MSW), current smokers had an increased prevalence and incidence of LR-HPV compared with never smokers.

CONCLUSIONS

Current smokers had a higher prevalence, persistence, and incidence of HPV compared with never smokers. Further research is needed to assess the role smoking in anal HPV persistence and progression to disease.

IMPACT

Prevention initiatives should raise awareness about smoking and the risk factor of anal HPV infection and anal cancer.

Sexual practices and HPV infection in unvaccinated young adults

The present study aimed to evaluate the association of genital and oral HPV infection among different sexual practices in both sexes. In total, 6388 unvaccinated men and women aged 16–25 years from all state capitals of Brazil were enrolled in through primary care services between September 2016 and November 2017. Genital and oral HPV genotyping was performed using the Roche Linear Array. Poisson regression analysis with robust variance was conducted to examine factors associated with overall HPV infection. A higher prevalence of genital HPV was found in women who practiced oral sex (57.85%) and in men who practiced all types of sex (65.87%). However, having more sexual partners and being younger were more important than the type of sex practiced. HPV 6 (7.1%) and 16 (10.5%) were significantly more prevalent in women who practiced oral sex, while HPV 6 (23.96%) and 11 (21.49%) were more prevalent in men who practiced anal sex. The type of sex was not associated with oral HPV prevalence. Genital and oral HPV infection were not associated by different sexual practices in the studied population.

Concurrent and Concordant Anal and Oral Human PapillomaVirus Infections Are Not Associated with Sexual Behavior in At-Risk Males

Men who have sex with men (MSM) harbor the highest prevalence of anal and oral Human Papillomavirus (HPV) infection, particularly if HIV-infected. We investigated anal and oral HPV infections in HIV-infected and HIV-uninfected MSM, to assess concurrent (HPV detected at both sites, irrespective of the genotypes), and concordant infections (same genotype[s] detected at both sites). Matched anal and oral samples from 161 MSM (85 HIV-infected, and 76 HIV-uninfected) were tested with the Linear Array. Determinants of concurrent and concordant infections were evaluated using logistic regression. Anal infections were 4 to 7 times more frequent than oral infections in both study groups (p < 0.0001). Concurrent infections were not significantly different in HIV-infected (25.9%) and HIV-uninfected MSM (17.1%), p = 0.18. A concordant infection was found in 15 MSM (9.3%). Concordance was for one genotype in 14 individuals and for four genotypes in the remaining subject. In the overall population, only age was independently associated with a concurrent infection (AOR = 3.10, 95% CI: 1.34–7.19 for >39 vs. ≤39 years). None of the parameters of sexual behavior showed independent association with concordant infections. Among MSM, concordant anal and oral HPV infections do not seem to be explained by sexual behavior, but might derive from sequential acquisition by autoinoculation.

Sequential acquisition of human papillomavirus infection between genital and oral anatomic sites in males

Oral human papillomavirus (HPV) is associated with increasing rates of HPV-associated oropharyngeal cancer (OPC) in men. Sequential infection from one site to another has been demonstrated at the cervix and anus. Thus, risk of an oral HPV infection after a genital infection of the same type in the HPV infection in men study was investigated. Samples from 3140 men enrolled in a longitudinal cohort were assessed for sequential genital to oral infection with one of nine HPV types (HPV 6, 11, 16, 18, 31, 33, 45, 52 and 58); and then also sequential, same-type oral to genital infection. Incidence rate ratios (IRRs) compared rates of oral HPV among men with and without prior genital infection of the same type. Risk of sequential HPV infections were assessed using Cox proportional hazards model. Incidence of an oral HPV infection was significantly higher among men with a prior genital infection of the same type for any of the 9 HPV types (IRR: 2.3; 95% CI: 1.7-3.0). Hazard ratio of a sequential genital to oral HPV infection was 2.3 (95% CI: 1.7-3.1) and 3.5 (95% CI: 1.9-6.4) for oral to genital infection. Both changed minimally after adjustment for age, country, circumcision, alcohol use, lifetime sexual partners and recent oral sex partners. HPV infections at one site could elevate risk of a subsequent genital or oral HPV infection of the same type in men, emphasizing the importance of vaccination to prevent all HPV infections.

Sequential Acquisition of Human Papillomavirus Infection at Genital and Anal Sites, Liuzhou, China

Little is known about the risk for acquiring a concordant human papillomavirus (HPV) infection in a genital (or anal) site after an anal (or genital) HPV infection. We collected 3 sets of anogenital specimens at 6-month intervals from 2,309 men and 2,378 women in Liuzhou, China, and tested these specimens for HPV. The risk for sequential anal HPV infection in participants with a previous genital HPV infection was higher than for participants without an infection (hazard ratio [HR] 4.4, 95% CI 3.4–5.8 for women and HR 2.6, 95% CI 1.4–4.6 for men). For sequential genital HPV infection, women with a previous anal infection had a higher risk (HR 1.9, 95% CI 1.2–3.1), but no major difference was found for men (HR 0.7, 95% CI 0.2–1.9). Our study indicates that autoinoculation might play a major role in anogenital HPV transmission, in addition to direct sexual intercourse, especially for anal infection in women.

Differences in Factors Associated With High- and Low-Risk Oral Human Papillomavirus Genotypes in Men

BACKGROUND

Human papillomavirus (HPV) causes oral warts and oropharyngeal cancer (OPC). Human papillomavirus-attributable OPC incidence among men is significantly increasing worldwide, yet few studies have reported oral HPV across multiple countries or examined factors associated with low- and high-risk HPV separately.

METHODS

Oral gargles from 3095 men in the multinational HPV Infection in Men (HIM) Study were HPV genotyped. Multivariable models assessed factors independently associated with high-risk and low-risk HPV prevalence.

RESULTS

The prevalence of high-risk and low-risk HPV was 6.0% and 2.8%, respectively. Greater number of sexual partners was only associated with high-risk HPV (1.88; 95% confidence interval [CI], 1.22-2.90) prevalence. In multivariable models, residing in Mexico (1.66; 95% CI, 1.15-2.40) and smoking (1.66; 95% CI, 1.13-2.44) were significantly associated with high-risk HPV, and history of consistent gum bleeding (2.16; 95% CI, 1.35-3.45) was significantly associated with low-risk HPV. Gender of the sexual partner did not alter the results for either high- or low-risk HPV endpoints.

CONCLUSIONS

Different factors were independently associated with high- and low-risk oral HPV. Oral sexual behaviors were associated with high-risk HPV, and oral health was associated with low-risk HPV. High-risk HPV prevalence differed by country of residence, highlighting the need for additional studies in multiple countries.

Prevalence and sociodemographic correlates of anogenital Human Papillomavirus (HPV) carriage in a cross-sectional, multi-ethnic, community-based Asian male population

Background

Addressing the burden of HPV-associated diseases among men is increasingly becoming a public health issue. The main objective of this study was to determine HPV prevalence among a healthy community-based Malaysian men.

Method

This was a cross-sectional study that recruited 503 healthy males from 3 community-based clinics in Selangor, Malaysia. Genital and anal samples were collected from each participant for 14 high risk and 2 low risk HPV DNA detection and genotyping. All participants responded to a set of detailed sociodemographic and sexual behaviour questionnaire.

Results

The median age at enrolment was 40 years old (IQR: 31–50). The anogenital HPV6/11 prevalence was 3.2% whereas high risk HPV prevalence was 27.1%. The genital HPV prevalence for HPV6/11 was 2.9% while high risk HPV was 18.8%. HPV6/11 prevalence in the anal canal was 1.6% and high risk HPV was 12.7%. HPV 18 was the most prevalent genotype detected in the anogenital area. There was a significant independent association between genital and anal HPV infections.

Conclusion

Anogenital HPV infection is common among Malaysian men. These findings emphasize the ubiquity of HPV infection and thus the value of population-wide access to HPV prevention.

Analysis of the prevalence of human papillomavirus and abnormal anal cytology in women at risk

Our aim was to analyze the association between anal human papillomavirus (HPV) infection and abnormal anal cytology in women with high-grade cervical intraepithelial neoplasia (CIN 2+). We also analysed what other risk factors might be significant. We carried out a prevalence study from April 2015 to March 2017 at La Paz University Hospital. Genotyping of HPV, anal cytology and high-resolution anoscopy were performed. Of 171 patients recruited, 53 cases (31%) were diagnosed as histological CIN 2+: there were no statistically significant differences in the prevalence of anal HPV (OR = 0.8), nor the prevalence of abnormal anal cytology (OR = 2.15, 95% CI 0.8-5.7) compared to women with CIN 1 or no cervical dysplasia. Immunosuppression (OR = 2.51, 95% CI 1-6.3, p < .05), cervical HPV (OR = 3.9, 95% CI 1.9-8.0, p < .01) and being older than 40 years old (p < .05) were also associated with anomalous anal results.Impact StatementWhat is already known on this subject? Anal HR-HPV and abnormal anal cytology may precede anal intraepithelial neoplasia (AIN): a premalignant lesion that may progress to anal cancer. It is known that there are four populations which present a higher risk of developing anal cancer compared to the general population: human immunodeficiency virus (HIV)-positive patients, other immunocompromised populations, men who have sex with men and women with a history of disease secondary to HPV infection.What do the results of this study add? This study allowed us to compare the prevalence of anal HPV and abnormal anal cytology in women with CIN 2+: it analysed whether these women already presented alterations in anal tests at the moment of the diagnosis of the preneoplastic cervical lesion. It also provides information for the management of the populations at a higher risk of developing anal cancer; specifically, the group of women with a prior history of HPV-associated anogenital disease.What are the implications of these findings for clinical practice and/or further research? Our findings improve the existing evidence on anal HPV infection and anal cytology on the least studied population at risk. Data could be useful for further research in order to clarify the role of anal screening in this population and standardise the clinical practice.

Diversity of human papillomavirus in the anal canal of HIV-positive and HIV-negative men

BACKGROUND

To characterize the HPV diversity in the anal mucosa of men with different sexual behavior and HIV status by next-generation sequencing (NGS).

METHODS

Anal swabs from HIV-positive (n = 94; mean age, 38 years) and HIV-negative (n = 100; mean age, 37.5 years) men who have sex with men (MSM) and HIV-negative men (predominantly men who have sex with women, MSW) (n = 99; mean age, 38.2 years) were analyzed by broad-spectrum PCR protocols combined with NGS.

FINDINGS

Alpha HPV types (n = 74) were detected mainly in the MSM groups (HPV6, 11, and 43 were the most abundant types) compared with MSW (n = 16) (HPV11, 32, and 87 were among the most abundant). In contrast, beta HPVs were more abundantly detected among MSW (n = 45) than in the HIV-positive (n = 16) and HIV-negative (n = 26) MSM groups. Gamma HPVs were detected almost equally in HIV-positive MSM (n = 62), HIV-negative MSM (n = 58), and MSW (n = 57). In addition, 31 putative novel PV types were identified.

CONCLUSIONS

Our data show that beta and gamma HPV types are present in the anal mucosa, thus reinforcing the existing evidence that they can be detected at anatomical sites other than skin. Alpha and beta HPV distribution among these three groups appears to vary according to sexual behavior.

Cervical, anal and oral HPV detection and HPV type concordance among women referred for colposcopy

BACKGROUND

Infection with human papillomaviruses (HPVs) can cause benign and malignant tumours in the anogenital tract and the oropharynx both in men and women. The aim of the presented study was to investigate cervical, anal, and oral HPV-detection rates among women referred to colposcopy for abnormal Cervical Cancer (CaCx) screening results and assess the concordance of HPV-types among these anatomical sites.

METHODS

Women referred to colposcopy at a single centre due to abnormal cytology, conducted for CaCx screening, were subjected to cervical Liquid-based Cytology (LBC) smear testing, anal and oral sampling. Routine colposcopy consisted in multiple biopsies and/or Endocervical Curettage (ECC). HPV-detection was performed by PCR genotyping in all three anatomical sites. In high-risk (hr) HPV-DNA positive samples either from anal canal or oral cavity, anal LBC cytology and anoscopy were performed, or oral cavity examination respectively. Descriptive statistics was used for the analysis of HPV-detection rates and phi-coefficient for the determination of HPV-positivity concordance between the anatomical sites.

RESULTS

Out of 118 referred women, hr. HPV-DNA was detected in 65 (55.1%), 64 (54.2%) and 3 (2.5%) at cervix, anal canal and oral cavity respectively while low-risk HPV-DNA was detected in 14 (11.9%) and 11 (9.3%) at cervix and anal canal respectively. The phi-coefficient for cervix/anal canal was 0.392 for HPV16, 0.658 for HPV31, 0.758 for HPV33, - 0.12 for HPV45, 0.415 for HPV52 and 0.473 for HPV58. All values were statistically significant (p < 0.001).

CONCLUSIONS

The results suggest that most HPV-types, high-risk and low-risk, detected in the cervix of women with prevalent cervical dysplasia, correlate with the ones detected in their anal canal. This particularly applies for the HPV-types included in the nonavalent HPV-vaccine (HPVs 6/11/16/18/31/33/45/52/58).

Integrating measures of viral prevalence and seroprevalence: a mechanistic modelling approach to explaining cohort patterns of human papillomavirus in women in the USA

Incidence of human papillomavirus (HPV) related cancers is increasing, generating substantial interest in understanding how trends in population prevalence of HPV infection are changing. However, there are no direct, population-scale measurements of HPV prevalence prior to 2003. Previous work using models to reconstruct historical trends have focused only on genital infection or seroprevalence (prevalence of antibodies) separately, and the results of these single-measure studies have been hard to reconcile. Here, we develop a mechanistic disease model fit jointly to cervicogential prevalence and seroprevalence in unvaccinated women in the USA using National Health and Nutrition Examination Survey data (2003-2010) and compare it to fits of statistical age-cohort models. We find that including a latent HPV state in our model significantly improves model fit and that antibody waning may be an important contributor to observed patterns of seroprevalence. Moreover, we find that the mechanistic model outperforms the statistical model and that the joint analysis prevents the inconsistencies that arise when estimating historical cohort trends in infection from genital prevalence and seroprevalence separately. Our analysis suggests that while there is substantial uncertainty associated with the estimation of historic HPV trends, there has likely been an increase in the force of infection for more recent birth cohorts. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.

Prevalence and incidence of anal human papillomavirus infection in Mexican men: Need for universal prevention policies

OBJECTIVE

Describe the natural history of anal HPV among men.

MATERIALS AND METHODS

Prospective study among men 18-70 years (n=665), from Cuernavaca, Mexico who completed questionnaires and provided specimens (HPV genotyped) at enrollment and 1+ follow-up visit. HPV prevalence and incidence were estimated. Prevalence ratios were calculated with Poisson regression using robust variance estimation. Person-time for incident HPV infection was estimated using number of events modeled as Poisson variable for total person-months.

RESULTS

Anal infection prevalence: any HPV type=15%, high-risk=8.4%, HPV16=1.4%, tetravalent vaccine types (4vHPV)=4.4%, nonavalent vaccine types (9vHPV)=6.3%. Factors associated with prevalence: 50+ lifetime female sex partners (adjusted prevalence ratio, a PR=3.25, 95% CI:1.12- 9.47), 10+ lifetime male sex partners (aPR=3.06, 95%CI:1.4- 6.68), and 1+ recent male anal sex partners (aPR=2.28, 95%CI:1.15-4.5). Anal incidence rate: high-risk HPV=7.8/1000 person-months (95%CI:6.0-10.1), HPV16=1.8/1000 personmonths (95%CI:1.1-2.9),4vHPV=3.4/1000 person-months (95%CI:2.3-4.9) and 9vHPV=5.5/1000 person-months (95%CI:4.1-7.5).

CONCLUSIONS

Implementation of universal HPV vaccination programs, including men, is a public health priority.

Anal cancer in high-income countries: Increasing burden of disease

BACKGROUND

Previous studies have reported that anal cancer incidence has increased in individual countries; however, age-specific trends were not examined in detail. This study describes pooled and country-specific anal cancer incidence trends by sex, age (all ages, <60 and 60+ years) and histological subtype (all subtypes, squamous cell carcinoma [SCC] and adenocarcinoma [ADC]).

METHODS

Five-year incidence and population-at-risk data were obtained from IARC's Cancer Incidence in Five Continents for the years 1988-1992 to 2008-2012. The standardised rate ratios (SRRs) for 2008-2012 vs 1988-1992 and the 5-year average percent change (AvPC) during the period were used to assess changes in the age-standardised incidence rates.

RESULTS

During the study period, there were significant increases in the incidence of SCC in both men and women of all age groups with significant increasing trend, and these increases were highest in those aged <60 years (SRR = 2.34 [95% CI:2.11-2.58] in men and SRR = 2.76 [95% CI:2.54-3.00] in women). By contrast, there were significant decreases in the incidence of ADC in men and women of all ages (SRR = 0.60 [95% CI:0.54-0.67]) and (SRR = 0.63 [95% CI:0.56-0.71], respectively), with similar decreases in those aged <60 years and 60+ years. These competing trends still resulted in significant increases in the overall incidence of anal cancer in men and women of all ages groups with significant increasing trend. The SRRs in men of all ages, <60 years and 60+ years were 1.35 (95% CI:1.28-1.42), 1.77 (95% CI:1.62-1.92) and 1.08 (95% CI:1.00-1.15), respectively. The corresponding SRRs in women were 1.75 (95% CI:1.67-1.83), 2.31 (95% CI:2.14-2.48) and 1.38 (95% CI 1.31-1.46), respectively.

CONCLUSION

Increases in the incidence of anal SCC has driven an overall increase in anal cancer incidence; this may be associated with changing sexual behaviours and increasing levels of HPV exposure in younger cohorts. The findings further reinforce the importance of HPV vaccination.

Dynamics and Determinants of HPV Infection: The Michigan HPV and Oropharyngeal Cancer (M-HOC) Study

INTRODUCTION

Human papillomavirus (HPV) is the primary cause of cervical and other anogenital cancers and is also associated with head and neck cancers. Incidence of HPV-related oropharyngeal squamous cell cancers (OPSCCs) is increasing, and HPV-related OPSCCs have surpassed cervical cancer as the most common HPV-related cancer in the USA. Given the multisite nature of HPV, there is strong interest in collecting data from both genital and oral sites, as well as associated data on social and sexual behaviours. The overarching goal of this study is to evaluate patterns of oral HPV infection incidence, clearance and persistence and their relationship to sexual behaviour history.

METHODS AND ANALYSIS

Participants are recruited from two populations: college students at a large public university and general population from the surrounding area. At the first study visit, participants complete a detailed sexual history, health and behaviour questionnaire. Follow-up visits occur every 3-4 months over 3 years, when participants complete an abbreviated questionnaire. All participants provide a saliva sample at each visit, and eligible participants may provide a cervicovaginal self-swab. Genetic material isolated from specimens is tested for 15 high-risk and 3 low-risk HPV types. Statistical analyses will examine outcome variables including HPV prevalence, incidence, persistence and clearance. Logistic regression models will be used to estimate odds ratios and 95% confidence intervals for associations between the outcomes of interest and demographic/behavioural variables collected in the questionnaires. The longitudinal HPV infection data and detailed sexual history data collected in the questionnaires will allow us to develop individual-based network models of HPV transmission and will be used to parameterise multiscale models of HPV-related OPSC carcinogenesis.

ETHICS AND DISSEMINATION

This study has been approved by the University of Michigan Institutional Review Board. All participants are consented in person by trained study staff. Study results will be disseminated through peer-reviewed publications.

Recurring infection with ecologically distinct HPV types can explain high prevalence and diversity

The high prevalence of human papillomavirus (HPV), the most common sexually transmitted infection, arises from the coexistence of over 200 genetically distinct types. Accurately predicting the impact of vaccines that target multiple types requires understanding the factors that determine HPV diversity. The diversity of many pathogens is driven by type-specific or "homologous" immunity, which promotes the spread of variants to which hosts have little immunity. To test for homologous immunity and to identify mechanisms determining HPV transmission, we fitted nonlinear mechanistic models to longitudinal data on genital infections in unvaccinated men. Our results provide no evidence for homologous immunity, instead showing that infection with one HPV type strongly increases the risk of infection with that type for years afterward. For HPV16, the type responsible for most HPV-related cancers, an initial infection increases the 1-year probability of reinfection by 20-fold, and the probability of reinfection remains 14-fold higher 2 years later. This increased risk occurs in both sexually active and celibate men, suggesting that it arises from autoinoculation, episodic reactivation of latent virus, or both. Overall, our results suggest that high HPV prevalence and diversity can be explained by a combination of a lack of homologous immunity, frequent reinfections, weak competition between types, and variation in type fitness between host subpopulations. Because of the high risk of reinfection, vaccinating boys who have not yet been exposed may be crucial to reduce prevalence, but our results suggest that there may also be large benefits to vaccinating previously infected individuals.

The EVVA Cohort Study: Anal and Cervical Type-Specific Human Papillomavirus Prevalence, Persistence, and Cytologic Findings in Women Living With HIV

Background

The risk of anal cancer due to high-risk human papillomavirus (HR-HPV) is higher in women living with human immunodeficiency virus (HIV) than in the general population. We present findings of cervical and anal HPV and cytologic tests at baseline in the EVVA cohort study and HPV persistence data 6 months after baseline.

Methods

Semiannual visits included questionnaires, chart reviews, cervical/anal cytologic and cervical/anal HPV testing for 2 years. Genotyping for 36 HPV genotypes was performed using the Roche Linear Array HPV genotyping test.

Results

A total of 151 women living with HIV were recruited. At baseline, 75% had anal HPV, 51% had anal HR-HPV, 50% had cervical HPV, and 29% had cervical HR-HPV. Anal HPV-16 and HPV-51 were more frequent in women born in Canada (31% and 29%, respectively, compared with ≤16% for other women). Most anal HR-HPV types detected at 6 months (57%-93%) were persistent from baseline. Findings of anal cytologic tests were abnormal for 37% of women.

Conclusions

Anal HPV is highly prevalent in women living with HIV, and type distribution varies by place of birth. High-resolution anoscopy was indicated in more than one third of results. As anal cancer is potentially preventable, these important findings need to be considered when selecting the best approach for anal cancer screening programs.

Concordance of Penile and Oral Human Papillomavirus Infections Among Men in the United States

This study examined the concordance of penile and oral human papillomavirus (HPV) infections in the United States. A total of 1683 men aged 18-59 years who participated in the 2013-2014 National Health and Nutrition Examination Survey and had results of oral and penile HPV DNA testing were examined. The prevalence of any HPV genotype was 45.3% on the penis, 11.2% in the oral cavity, and 8.8% at both sites. The prevalence of HPV in the oral cavity was higher among those with than among those without penile HPV infection (19.3% vs 4.4%; prevalence ratio, 4.37 [95% confidence interval, 2.66-7.16]). The prevalence of ≥1 genotype-concordant HPV infection was 3.2% and was associated with sexual behavior, independent of demographic characteristics and smoking status. Sexual behavior may partly explain the observed association between penile and oral HPV infections.

Comparison of anal HPV natural history among men by country of residence: Brazil, Mexico, and the United States

OBJECTIVES

Globally, anal cancer incidence is rare, but is increasing in some world regions. Our objective was to assess differences in anal HPV natural history in three countries.

METHODS

Men aged 18-70 years were recruited from the US (n = 634), Mexico (n = 665), and Brazil (n = 731). Anal specimens were collected every six-months. HPV genotyping was assessed by Linear Array. Anal HPV prevalence was compared using the Fisher's exact test. HPV infection incidence rates (IR) and 95% confidence intervals (CI) were calculated.

RESULTS

Any anal HPV prevalence was highest among men from Brazil (24%) compared to Mexico (15%) and the US (15%). When stratified by sexual history, the prevalence of any HPV among MSM/MSMW was 43%, 37%, and 45% and 9%, 12%, and 10% for MSW from Brazil, Mexico, and US, respectively. Any HPV incidence was significantly higher among men from Brazil compared to US men (IRR = 2.4, 95% CI = 1.7-3.4) and comparable between men from Mexico and the US (IRR = 1.2, 95% CI = 0.8-1.8).

CONCLUSION

Men in Brazil and Mexico often have similar, if not higher incidence of anal HPV compared to men from the U.S., and may benefit from gender neutral HPV vaccine policies.