Screening for HIV-associated anal cancer: correlation of HPV genotypes, p16, and E6 transcripts with anal pathology

Human papillomavirus-associated anal squamous intraepithelial lesions in men who have sex with men and transgender women living with and without HIV in Karachi Pakistan: implications for screening and prevention

BACKGROUND

Anal squamous intraepithelial lesions (ASIL), strongly related to human papilloma virus (HPV) infection, is more prevalent among men who have sex with men (MSM). However, no such data are available for Pakistan yet, and neither HPV vaccination nor anal-cytology screening is implemented in Pakistan. The purpose of this first ever study was to assess the prevalence of HPV-related anal cytological abnormalities among MSM and transgender women living with and without HIV infection in Pakistan.

METHODS

We conducted a cross-sectional study from March 2016 to November 2017 at sexual health centers run by the Perwaaz Trust and the National AIDS Control Program in Karachi. The study enrolled MSM and transgender women aged greater-than-and-equal-to-18-years who reported anal sex in the preceding 6 months. We collected two anal samples for liquid-based cytology and HPV type testing by PCR, and socio-demographic and behavioral data were collected through face-to face interviews. ASIL and its associations with biological and behavioral risk factors were analyzed through Cox regression for prevalence ratios (PR) and corresponding 95% confidence intervals (CIs).

RESULTS

Out of 271 qualifying participants, 79% were MSM and 21% transgender women. The mean age was 28.8 (± 8) years. Almost 35% (93/271) of the study population had ASIL detected, ASIL was significantly more common among participants living with HIV than in HIV negative ((50/118) 42.4%; vs. (43/153) 28.1%) (p ≤ 0.001). Among ASIL, 66% (61/93) had low-grade squamous intraepithelial lesions (LSIL), and 3.6% (3/93) had high-grade squamous intraepithelial lesions (HSIL). The overall, HPV16 positivity was 35.5% (33/93) among all abnormal anal lesions and all 3 HSIL were HPV16 positive, however, HPV16 positivity could show its association with ASIL detection in univariate model only (PR_crude: 2.11(1.39-3.18)). Moreover, any HR-HPV type (PR 3.04; 95% CI 1.75-5.26), concurrent sexually transmitted infection (STI) (2.13; (1.28-3.55)) and HIV + /HPV + coinfection (1.75; (1.07-2.88)) remained independently associated with ASIL in the multivariate model.

CONCLUSIONS

Abnormal anal cytology among MSM and transgender is prevalent enough to consider optimal screening regimens. Further studies are required to see if periodic anal cytology can be made part of HIV care and treatment programs among MSM in Pakistan.

Anal Squamous Intraepithelial Lesions (SILs) in Human Immunodeficiency Virus-Positive Men Who Have Sex With Men: Incidence and Risk Factors of SIL and of Progression and Clearance of Low-Grade SILs

BACKGROUND

Human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) are at risk of anal squamous cell carcinoma. Data are limited on the natural history of the precursor to this carcinoma, anal squamous intraepithelial lesions (SILs).

METHODS

HIV-positive MSM were screened for histopathological SILs by means of high-resolution anoscopy (HRA). For participants without SILs at baseline, we estimated the cumulative incidence and risk factors for SILs. For those with low-grade SILs (LSILs) at baseline, the risk of progression to high-grade SILs (HSILs) and the clearance rate were estimated at the lesion level.

RESULTS

Of 807 men without SILs at baseline, 107 underwent follow-up HRA between 1 to 4.5 years later. At the second visit 18 men (16.8%) showed LSIL, and 25 (23.4%) HSIL. Age was associated with incident LSILs (adjusted odds ratio [aOR], 2.10 per 10-year increase in age; P = .01). Of 393 men with LSILs at baseline, 114 underwent follow-up HRA 0.5 to 2.5 years later. Of the 177 LSILs found at baseline, 87 (49.2%) had cleared at the second visit, and 29 (16.4%) had progressed to HSILs.

CONCLUSION

Incident LSILs and HSILs were common during follow-up among HIV-positive MSM without dysplasia at baseline. Among men with LSILs at baseline, nearly half of these lesions cleared, and a small portion progressed.

Viruses in Cancers of the Digestive System: Active Contributors or Idle Bystanders?

The human virome, which is a collection of all the viruses that are present in the human body, is increasingly being recognized as an essential part of the human microbiota. The human gastrointestinal tract and related organs (e.g., liver, pancreas, and gallbladder)-composing the gastrointestinal (or digestive) system-contain a huge number of viral particles which contribute to maintaining tissue homeostasis and keeping our body healthy. However, perturbations of the virome steady-state may, both directly and indirectly, ignite/sustain oncogenic mechanisms contributing to the initiation of a dysplastic process and/or cancer progression. In this review, we summarize and discuss the available evidence on the association and role of viruses in the development of cancers of the digestive system.

Significance of bacterial and viral genotypes as a risk factor in driving cancer (Review)

Microbes have been known to drive human cancers for over half a century. However, despite the association of bacterial and viral infections with a high risk of cancer, most infections do not result in the development of cancer. Additionally, certain bacteria and viruses, considered to drive oncogenesis, are commonly prevalent in the global population. The current study performed a comprehensive meta-analysis of primary literature data to identify particular aspects of microbial genotypes as crucial factors that dictate the cancer risks associated with infection. The results indicated the importance of incorporating microbial genotype information with human genotypes into clinical assays for the more efficient diagnosis and prognosis of patients with cancer. The current review focuses on the importance of microbial genotypes and specific genes and genetic differences that are important to human oncogenesis.

Association of antiretroviral therapy with anal high-risk human papillomavirus, anal intraepithelial neoplasia, and anal cancer in people living with HIV: a systematic review and meta-analysis

BACKGROUND

The effect of antiretroviral therapy (ART) on the natural history of anal high-risk HPV and anal lesion progression is not well established. We reviewed the association of ART and other HIV-related factors on anal HPV infection, anal intraepithelial neoplasia (AIN), and anal cancer among people living with HIV.

METHODS

For this systematic review and meta-analysis, we searched MEDLINE and EMBASE for studies published between Jan 1, 1996, and Oct 30, 2019, that reported the association of HIV-related exposures (ART or highly active ART [HAART], HIV-RNA plasma viral load [PVL], and nadir or current CD4 cell count) with outcomes of anal high-risk HPV prevalence, incidence, and persistence; prevalence, incidence, progression, or regression of anal histological and cytological abnormalities; and anal cancer incidence. Effect estimates were extracted whenever available; otherwise, they were calculated from raw data. We assessed the risk of bias of included studies using the Newcastle-Ottawa scale, and random-effects meta-analyses were done to examine heterogeneity using the I² statistic. This study is registered on the PROSPERO database, CRD42018007271.

FINDINGS

We identified 6777 studies, of which 5377 were excluded before full-text review. 122 studies providing estimates for 130 distinct populations matched the inclusion criteria. The populations comprised 417 006 people living with HIV (women, men who have sex with men, and men who have sex with women). 41 (32%) population estimates were not stratified by sex or sexual orientation. People living with HIV receiving ART had 35% lower high-risk HPV prevalence than ART-naive people (crude odds ratio [OR] 0·65, 95% CI 0·54-0·79; I² 12·1%, p=0·31) in 18 studies, and prolonged ART use was associated with a 10% reduction per year in high-risk HPV prevalence in two studies (adjusted OR 0·90, 0·85-0·95; I² 0%, p=0·88). People living with HIV with undetectable PVL had lower HSIL-AIN2+ prevalence than those with detectable PVL (crude OR 0·84, 0·72-0·98; I² 0%, p=0·80) in 16 studies, particularly if sustained for more than 1 year (crude OR 0·62, 0·47-0·81; I² 0%, p=0·51). ART was not associated with anal cancer incidence when adjusted for years living with HIV in three studies (adjusted hazard ratio [HR] 1·11, 95% CI 0·68-1·80; I² 0%, p=0·57), but ART users with sustained undetectable HIV PVL had 44% lower risk of anal cancer than those without (adjusted HR 0·56, 0·44-0·70; I² 0%, p=0·94) and for each increase in nadir CD4 cell counts of 100 cells per μL, there was a 40% decrease in anal cancer incidence (crude HR 0·60, 0·46-0·78; I² 21·7%, p=0·26).

INTERPRETATION

Effective ART use and early initiation at high nadir CD4 counts might reduce anal high-risk HPV infection and anal cancer risk. Although most studies were cross-sectional in design and few adjusted for potential confounders, this analysis provides comprehensive estimates of the effect of ART and HIV-related factors on the natural history of anal HPV-related disease in people living with HIV.

FUNDING

EU Marie Skłodowska-Curie Actions programme.

The Accuracy of Anal Swab-Based Tests to Detect High-Grade Anal Intraepithelial Neoplasia in HIV-Infected Patients: A Systematic Review and Meta-analysis

Background

The incidence of high-risk human papillomavirus (HR-HPV)–induced anal cancer is increasingly problematic among HIV-positive patients. Anal cancer is preceded by precursor lesions, anal intraepithelial neoplasia (AIN). AIN detection requires high-resolution anoscopy, a cumbersome and time-consuming procedure. We aggregated evidence on anal swab–based tests to detect AIN in HIV-positive patients.

Methods

We searched MEDLINE and EMBASE for cross-sectional studies on AIN detection with anal cytology, HR-HPV DNA detection, HPV E6/E7 mRNA analysis, and P16INK4a and Ki-67 immunostaining. Summary estimates of sensitivity and specificity were calculated using bivariate logistic regression. Cytology was reported using the terms squamous intra-epithelial lesion (SIL) for AIN and high-grade SIL (HSIL) for high-grade AIN (HGAIN).

Results

We included 22 studies. Using cytology with a cutoff of any SIL to detect HGAIN, we detected a sensitivity of 82% (95% CI, 74%–87%) and specificity of 45% (95% CI, 44%–66%); with the cutoff of HSIL, the sensitivity was 44% (95% CI, 45%–67%) and the specificity was 79% (95% CI, 69%-87%). The sensitivity of HPV DNA to detect HGAIN was 91% (95% CI, 82%–95%) and the specificity was 27% (95% CI, 21%–33%). For MSM, the positive predictive value (PPV) of cytology with a cutoff of any SIL was 36% (95% CI, 23%–50%) and the negative predictive value (NPV) was 87% (95% CI, 78%–93%), whereas cytology with a cutoff of HSIL had a PPV of 62% (95% CI, 50%–73%) and an NPV of 78% (95% CI, 65%–87%). The PPV of HR-HPV DNA detection was 37% (95% CI, 20%–57%) and the NPV was 87% (95% CI, 79%–93%).

Conclusions

Given its sensitivity, cytology with a cutoff of any SIL could be considered as a triaging method, whereas cytology with a cutoff of HSIL had better specificity and could be used for quality assurance. HR-HPV DNA detection had poor specificity and PPV, making it unsuitable for triage.

Anal intraepithelial neoplasia: diagnosis, screening, and treatment

Anal intraepithelial neoplasia (AIN) is a premalignant lesion for anal cancer. It is more commonly found in high-risk patients (e.g., human papilloma virus (HPV)/human immunodeficiency virus infections, post-organ transplantation patients, and men who have sex with men) and development is driven by HPV infection. The incidence of AIN is difficult to estimate, but is heavily skewed by preexisting conditions, particularly in high-risk populations. The diagnosis is made from cytology or biopsy during routine examinations, and can be performed at a primary care provider’s office. A pathologist can then review and classify cells, based on nucleus-to-cytoplasm ratios. The classification of low or high grade can better predict progression from AIN to anal cancer. There is little debate that AIN can develop into anal cancer, and the main rationale for treatment is to delay the progression. Significant controversy remains regarding screening, surveillance, and treatment for AIN. Management options are separated into surveillance (watchful waiting) and interventional strategies. Emerging data suggest that close patient follow up with a combination of ablative and topical treatments may offer the greatest benefit. HPV vaccination offers a unique treatment prior to HPV infection and the subsequent development of AIN, but its use after the development of AIN is limited. Ablative treatment includes excision, fulguration, and laser therapy.

Methylation of HPV and a tumor suppressor gene reveals anal cancer and precursor lesions

We studied DNA methylation patterns of human papillomavirus (HPV) and tumor suppressor gene EPB41L3 in 148 anal and perianal biopsies to determine whether high levels of methylation would be associated with anal intraepithelial neoplasia (AIN). The most prevalent HPV type was HPV16, detected in 54% of the 30 benign biopsies, 33% of the 43 low-grade AIN (lgAIN), 82% of the 59 high grade AIN (hgAIN) and 4 of the 5 anal cancers. A methylation score was developed (0.561*HPV16me+0.439*EPB41L3) which had increasing values with severity of disease: the mean was 8.1% in benign, 13.2% in lgAIN, 22.3% in hgAIN and 49.3% in cancers (p < 0.0001). The methylation score as a triage classifier at a cut-off of 8.8 gave a sensitivity of 90.6% (95% CI: 82.8, 96.9), specificity of 50.7% (95% CI: 39.7, 61.6) and area under the curve of 0.82 (95% CI: 0.75-0.89) for separating hgAIN and cancer from benign and lgAIN biopsies. We conclude that methylation of HPV16 and EPB41L3 show highly significant association with increasing severity of AIN and cancer and may be useful as biomarkers in anal disease.

Characterization of topoisomerase II α and minichromosome maintenance protein 2 expression in anal carcinoma

The present study aimed to ascertain the significance of topoisomerase II α (TOP2A) and minichromosome maintenance protein (MCM) 2 expression in anal carcinoma. A total of 75 anal lesions were retrieved from the files of the Department of Pathology of Barretos Cancer Hospital (Barretos, Brazil) in order to verify the human papillomavirus (HPV) statuses of these lesions and characterize the immunohistochemical expression levels of TOP2A and MCM2 in anal carcinoma, as these are important markers for cervical HPV-induced lesions; their expression was also compared with respect to p16 and Ki-67. The vast majority of the cases tested positive for HPV16 (84%); 1 case tested positive for both HPV16 and HPV18. Positive HPV16 status was more frequent in early stages than in advanced stages (P=0.008). Positive immunohistochemical reactivity for MCM2 and TOP2A protein was observed in 71.6 and 100% of cases, respectively. Positive reactivity for p16 was significantly associated (P=0.001) with histological grade, and was more commonly expressed in squamous cell carcinoma than adenocarcinomas. HPV16 was strongly associated with positive p16 protein expression (76.6%). However, the high expression of Ki-67 combined with the high expression of p16 was predominantly observed in Stage III-IV cases. MCM2, TOP2A, p16 and Ki-67 exhibited intense positive staining in the anal lesions, indicating that these markers were significantly and constantly expressed in anal carcinoma.

Anal human papillomavirus infection: prevalence, diagnosis and treatment of related lesions

Human papillomavirus (HPV) infection is mostly asymptomatic, but may also have many diverse clinical signs encompassing benign ano-genital lesions, and carcinomas. Recently, interest has also particularly focused on anal cancer since, over the last decades, its incidence has been greatly increasing in developed countries, both in women and men and is drastically higher in specific risk groups, such as men who have sex with men (MSM) and HIV-1 infected individuals. Approximately 88% of anal cancer cases worldwide are associated with HPV infection. This review summarizes our current understanding of anal HPV infection, discussing its epidemiology and risk factors in various populations, and the state of the art in the detection of anal HPV infection and its related lesions through both cytology and histology. Finally, we discuss the clinical management and therapy for these lesions.

Human Papillomavirus and Genital Warts: A Review of the Evidence for the 2015 Centers for Disease Control and Prevention Sexually Transmitted Diseases Treatment Guidelines

To provide updates for the 2015 Centers for Disease Control and Prevention sexually transmitted diseases treatment guidelines on human papillomavirus (HPV) and anogenital warts (AGWs), a review of the literature was conducted in key topic areas: (1) epidemiology and burden of disease; (2) transmission and natural history; (3) diagnosis and management of AGWs; (4) occupational exposure of healthcare workers; (5) anal cancer screening among men who have sex with men (MSM); and (6) HPV vaccine recommendations. Most sexually active persons will have detectable HPV at least once in their lifetime; 14 million persons are infected annually, and 79 million persons have prevalent infection. HPV is transmitted frequently between partners; more frequent transmission has been reported from females to males than from males to females. A new formulation of imiquimod (3.75% cream) is recommended for AGW treatment. Appropriate infection control, including performing laser or electrocautery in ventilated rooms using standard precautions, is recommended to prevent possible transmission to healthcare workers who treat anogenital warts, oral warts, and anogenital intraepithelial neoplasias (eg, cervical intraepithelial neoplasia). Data are insufficient to recommend routine anal cancer screening with anal cytology in persons living with human immunodeficiency virus (HIV)/AIDS or HIV-negative MSM. An annual digital anorectal examination may be useful for early detection of anal cancer in these populations. HPV vaccine is recommended routinely for 11- or 12-year-olds, as well as for young men through age 21 years and young women through age 26 years who have not previously been vaccinated. HPV vaccine is also recommended for MSM, people living with HIV/AIDS, and immunocompromised persons through age 26 years.

Anal cancer screening knowledge, attitudes, and experiences among men who have sex with men in Ottawa, Ontario

Anal cancer is rare; however, men who have sex with men (MSM) are at significantly increased risk compared to the general population. In Canada, no widespread screening programs nor accepted standards of care exist to inform primary care physicians (PCP) regarding screening and prevention for MSM patients. Our objective was to assess the knowledge, attitudes and experience of a sample of MSM regarding anal cancer risk, screening, prevention, and acceptability of HPV vaccination. A cross-sectional survey was conducted at an STI clinic for MSM in Ottawa, Ontario over a 20-week period. Descriptive statistics, Pearson's Chi-square test and binary logistic regression for comparisons between groups were completed. Fifty-five percent of respondents were aware of increased anal cancer risk among MSM; 47.7% were aware that HPV is the primary cause. Only 14.8% of men with a PCP had discussed anal cancer screening and prevention with their PCP. Of those who had not, 86.0% indicated they would be comfortable having that discussion. Just under 8% reported receiving an appropriate screening test. The HPV vaccination rate was 16.2%. The majority of respondents who had not been vaccinated expressed openness to vaccination. A clear deficiency was observed in terms of MSM knowledge regarding anal cancer risk and inclusion of this health concern in their primary care. This highlights the need for more discussion between MSM and their PCPs to ensure MSM are aware of their risk and of available screening and prevention options recognizing the limited evidence-base for anal cancer screening.

Cytology as a screening tool for anal squamous intraepithelial lesion for HIV positive men: 10-year experience in an inner city hospital

INTRODUCTION

Human papillomavirus (HPV) and anal carcinoma are prevalent in high-risk patients including human immunodeficiency virus (HIV)-positive patients. There are currently no clear guidelines for screening, however. We assessed anal cytology specimens and HPV testing at an inner-city hospital by correlating anal cytology with anal biopsy (bx), and evaluated if results differed with traditional proctoscopy (TP) or high-resolution anoscopy (HRA).

MATERIALS AND METHODS

209 anal cytology and subsequent biopsies taken during the period 2003-2014 from 152 male patients were reviewed. Demographic data for age, sex, HIV, HPV, cytology, histology, and the method of biopsy were analyzed.

RESULTS

All specimens were followed by a biopsy within a period of 6 months. Ninety-seven percent of patients were HIV-positive and 43% had AIDS. Lesions most diagnosed on cytology were low-grade squamous intraepithelial lesion (LSIL) (52%) and atypical squamous cells of undetermined significance (ASC-US) (21.5%). Lesions most diagnosed on bx were anal intraepithelial neoplasia (AIN) grade 2-3 (52%) and AIN grade 1 (37%). Almost all ASC-US cases tested for HPV were positive (97%). There was cytology histology correlation in 48% of LSIL and 83% of high-grade squamous intraepithelial lesions. Anal cytology had 97% sensitivity in detecting AIN and carcinoma and a positive predictive value of 96%. There was no difference in rate of detection of AIN 1and AIN 2-3 on bx using TP versus HRA.

CONCLUSION

Screening in high-risk patients detected almost all high- and low-grade squamous intraepithelial lesions, however, anal cytology alone could not predict the degree of dysplasia. It may be prudent to perform anal bx in all atypical anal cytology. Clear guidelines are needed for screening of a high risk population.

Incidence and Predictors of Abnormal Anal Cytology Findings Among HIV-Infected Adults Receiving Contemporary Antiretroviral Therapy

BACKGROUND

Anal cancer rates are higher for human immunodeficiency virus (HIV)-infected adults than for uninfected adults. Limited published data exist characterizing the incidence of precursor lesions detected by anal cytology.

METHODS

The Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy was a prospective cohort of 700 HIV-infected participants in 4 US cities. At baseline and annually thereafter, each participant completed a behavioral questionnaire, and healthcare professionals collected anorectal swabs for cytologic examination and human papillomavirus (HPV) detection and genotyping.

RESULTS

Among 243 participants with negative baseline results of anal cytology, 37% developed abnormal cytology findings (incidence rate, 13.9 cases/100 person-years of follow-up; 95% confidence interval [CI], 11.3-16.9) over a median follow-up duration of 2.1 years. Rates among men having sex with men, among women, and among men having sex with women were 17.9 cases/person-years of follow-up (95% CI, 13.9-22.7), 9.4 cases/person-years of follow-up (95% CI, 5.6-14.9), and 8.9 cases/person-years of follow-up (95% CI, 4.8-15.6), respectively. In multivariable analysis, the number of persistent high-risk HPV types (adjusted hazard ratio [aHR], 1.17; 95% CI, 1.01-1.36), persistent high-risk HPV types except 16 or 18 (aHR, 2.46; 95% CI, 1.31-4.60), and persistent types 16 or 18 (aHR, 3.90; 95% CI, 1.78-8.54) remained associated with incident abnormalities.

CONCLUSIONS

The incidence of abnormal anal cytology findings was high and more likely to develop among persons with persistent high-risk HPV.

Use of human papillomavirus genotyping and biomarkers for targeted screening of anal dysplasia in human immunodeficiency virus-infected patients

BACKGROUND

Screening for anal dysplasia in human immunodeficiency virus (HIV)-infected patients is not standardized. High-resolution imaging is not adequate for mass screening, and anal cytology requires expertise. New biomarkers, selected because of their use in cervical cancer mass screening, have been originally tested for targeted and easy-to-perform screening.

METHODS

120 HIV-infected individuals (males 96.4%, mean age 47±11 years) were referred for clinical examination, anoscopy, and cytological studies on anal swab. Dysplasia grading, Human Papilloma Virus genotyping, E6/E7mRNA detection and p16(INK4A)/Ki-67 immunostaining were performed. High-grade lesions were histologically confirmed by anal biopsies after high-resolution anoscopy.

RESULTS

Among the 120 anal swabs analyzed, 36 (30%) had low grade and 6 (5%) had high-grade lesions. Virus genotype was identified in 88 patients (73.3%), and 77 (64.2%) were positive for high-risk genotype(s). High-risk genotype was associated to low-grade or high-grade lesions with a sensitivity of 0.93 and a specificity of 0.51. For E6/E7mRNA, sensitivity and specificity for low-grade and high-grade lesions were, respectively, 0.88 and 0.78. Combination of genotyping, E6/E7mRNA and p16(INK4A)/Ki-67 appropriately ruled out dysplasia in 55% of patients.

CONCLUSIONS

Three routine biomarkers may avoid unnecessary invasive procedures with the perspective of an improvement of patient compliance. A decision making algorithm, based on the combination of these three biomarkers, is proposed.

Risk factors for anal HPV-16/18 infection in Mexican HIV-infected men who have sex with men

OBJECTIVE

To describe the prevalence of specific HPV types among HIV-positive men who have sex with men (MSM), particularly the presence of HPV-16 and/or -18, and to determine the factors associated with anal HPV-16/18 infections.

METHODS

This is a cross-sectional study from a baseline cohort of 525 HIV-positive MSM, who attended an HIV Clinic in Mexico City. Socio-demographic characteristics, sexual behaviors and HIV-related parameters were assessed. Anal samples were tested for HPV DNA using the Linear Array HPV genotyping assay.

RESULTS

The overall prevalence of any HPV type in the anal canal among 446 participants was 93.1%. At least one oncogenic HPV type was detected in 72.2% of the subjects and HPV-16 and/or18 were detected in 30.7%. Additionally, 76.9% of patients were infected with multiple HPV types. Having more than 10 receptive sexual partners in the last 6months (OR=2.30; 95% CI 1.12-4.74) and a CD4 cell count ≤350cells/μL (OR=1.97; 95% CI 1.26-3.09) were factors positively associated with HPV-16/18 infection in the anal canal.

CONCLUSION

Co-infection with HPV-16/18 and other oncogenic types are predominant in this group of HIV-positive MSM. The recognition of infection with specific oncogenic types will be of aid in designing future preventive strategies that target this high-risk population.

The prognostic value of HPV status and p16 expression in patients with carcinoma of the anal canal

Background

In anal cancer studies, the detection frequency of high-risk HPV (human papillomavirus) is variable, depending on the method used. There are limited data reporting results of different HPV detection techniques in the same clinical series, and very few correlating results with clinical outcome.

Objectives

To evaluate tumor expression of p16/HPV16 using three different methods, and to determine their association with clinical outcome in patients with anal canal squamous cell carcinomas (SCC).

Design

This retrospective study included patients with anal canal SCC treated with definitive radiotherapy or chemoradiotherapy at a single institution between 1992 and 2005. Formalin-fixed paraffin–embedded tumor samples from 53 of the 89 (60%) patient pre-treatment biopsies were adequate for tissue microarray construction. HPV status was determined using: p16 expression by conventional immunohistochemistry (IHC) and quantitative IHC (AQUA), HPV genotype analysis by chromogenic in situ hybridization (CISH) and HPV linear array sub-typing. Expression status was correlated with clinical outcome.

Results

80% (28/35) of patient tumors had high p16 expression using conventional IHC. HPV16 CISH was positive in 81% (34/42) of tumors, and 78% (28/36) of tumors were HPV subtype 16. HPV16 CISH correlated with p16 evaluated by conventional IHC (correlation coefficient 0.46; p = 0.01) and by p16 AQUA score (correlation coefficient 0.49; p = 0.001). A subset of cases (15%) had very high p16 quantitative IHC scores (>244) and were associated with a higher incidence of local or distant recurrence (p = 0.04).

Conclusions

The vast majority (80%) of anal canal SCC in our series were positive for HPV16/p16, regardless of the testing method used. The exploratory analysis of automated quantitative IHC scoring was the only technique to define a subset of patients with a worse prognosis by p16 expression status on univariate analysis. Further exploration of the molecular mechanisms of treatment resistance in association with very high p16 expression is warranted.

Site of infections associated with human papillomavirus

INTRODUCTION

Human papillomavirus (HPV) is the most clinically common sexually transmitted infection due to its carcinogenic power and the high number of lesions that it causes at different sites of the human body.

MATERIAL AND METHODS

Genital tract organs are the most common sites where the virus can be found, but by increasing the sensitivity of diagnostic technique, it is possible to identify viral presence in different regions of the body such as the stomach, the lung, and the urinary tract. These findings break with the traditional HPV skin/genital tropic profile and demonstrate that the virus is capable of infecting a wide variety of cells, tissues, and organs or can, at least, survive in these areas. The widespread presence of the HPV in the human body, often in latent form, led us to consider the hypothesis that HPV latency may be associated with no disease.

CONCLUSION

This observation raises further questions about the possibility of the virus not causing disease in specific sites of the human body, but rather, behaving like a commensal/opportunistic microorganism.

Does high-risk human papilloma virus genotyping of abnormal anal cytology improve detection of high-grade anal intraepithelial neoplasia?

INTRODUCTION

High-risk (HR) human papillomavirus (HPV) testing is accepted as the standard of care for surveillance of cervical cancer. Its role in anal cancer is not clear. This study was therefore designed to determine if HR HPV genotyping is a useful adjunct in management of abnormal anal Papanicolaou (Pap) tests.

MATERIALS AND METHODS

HR HPV genotyping and virus quantification was performed on 101 residual anal Pap test samples (28 negative, 25 atypical squamous cells of undetermined significance [ASC], 34 low-grade squamous intraepithelial lesion [LSIL], 6 atypical squamous cells of undetermined significance, cannot exclude high-grade squamous intraepithelial lesion, and 8 high-grade squamous intraepithelial lesion) using multiplex real-time polymerase chain reaction. Results were correlated with cytodiagnosis and follow-up.

RESULTS

HR HPV was detected in 82% (50% negative, 84% ASC, and 100% LSIL and above) cases. Multiple genotypes were present in 71% of cases. Genotype number and viral load correlated with the degree of anal cytologic abnormality. HPV 16, 18, and 45 were the most frequent genotypes detected. The high frequency of HR HPV in abnormal anal cytologies limits its use as an adjunct test. Anal Pap test samples with anal intraepithelial neoplasia 2/3 (AIN 2/3) on follow-up were positive for HPV 16 and/or 18 (HPV 16/18+) in 80% of cases. We hypothesize that testing for HPV 16/18 on the ASC and LSIL cases would have detected AIN 2/3 with a sensitivity of 81%, specificity of 43%, positive predictive value of 39%, and negative predictive value of 83%.

CONCLUSIONS

Our results with a small cohort suggest that genotyping for HPV 16/18 may be effective in identifying patients at high risk for anal cancer and in reducing the number of anoscopy referrals. Prospective studies with follow-up are warranted.

Risk Factors for the presence of anal intraepithelial neoplasia in HIV+ men who have sex with men

Objective

Anal Intraepithelial Neoplasia (AIN) is present in the majority of HIV+ men who have sex with men (MSM) and routine AIN-screening is subject of discussion. In this study we analysed a wide range of potential risk factors for AIN in order to target screening programs.

Methods

We screened 311 HIV+ MSM by high resolution anoscopy, with biopsies of suspect lesions. HIV-parameters, previous sexual transmitted infections (STI’s), anal pathology, sexual practices and substance use were analysed in relation to AIN by uni- and multivariable logistic regression.

Results

AIN (any grade) was found in 175/311 MSM (56%), high grade (HG)AIN in 30%. In the univariable analysis, years since HIV diagnosis, years of antiretroviral therapy (cART) and anal XTC use decreased AIN risk, while a history of anogenital warts and use of GHB (γ-hydroxybutyric acid) increased this risk. In the multivariable analysis three parameters remained significant: years of cART (OR=0.92 per year, p=0.003), anal XTC use (OR=0.10, p=0.002) and GHB use (OR=2.60, p=0.003). No parameters were significantly associated with HGAIN, but there was a trend towards increased risk with anal enema use prior to sex (>50 times ever; p=0.07) and with a history of AIN (p=0.06). CD4 count, STI’s, anal pathology, smoking, number of sex partners and anal fisting were not associated with (HG)AIN.

Conclusion

GHB use increases the risk for AIN, while duration of cART and anal XTC use are negatively correlated with AIN. Given the high prevalence of AIN in HIV+ MSM, these associations are not helpful to guide a screening program.

Use of human papillomavirus DNA, E6/E7 mRNA, and p16 immunocytochemistry to detect and predict anal high-grade squamous intraepithelial lesions in HIV-positive and HIV-negative men who have sex with men

Background

Men who have sex with men (MSM) are at high risk of having anal cancer. Anal high-grade squamous intraepithelial lesion (HSIL) is the precursor of anal cancer. We explored the use of different biomarkers associated with human papillomavirus (HPV) infection and HPV-mediated cell transformation to detect and predict HSIL among HIV-positive and HIV-negative MSM.

Methodology/Principal Findings

A total of 123 HIV-positive and 123 HIV-negative MSM were enrolled and followed for 12 months. High-resolution anoscopy (HRA) with biopsies were performed at every visit along with anal sample collection for cytology, high-risk HPV DNA genotyping, HPV E6/E7 mRNA, and p16 immunocytochemistry. Performance characteristics and area under the receiver operator characteristics curve were calculated for these biomarkers at baseline, and Cox regression compared the usefulness of these biomarkers in predicting incident HSIL. High-risk HPV DNA, E6/E7 mRNA, and p16 immunocytochemistry each identified 43–46% of MSM whose baseline test positivity would trigger HRA referral. E6/E7 mRNA had the highest sensitivity (64.7%) and correctly classified the highest number of prevalent HSIL cases. With the exception of p16 immunochemistry, most tests showed significant increases in sensitivity but decreases specificity versus anal cytology, while the overall number of correctly classified cases was not significantly different. Baseline or persistent type 16 and/or 18 HPV DNA was the only test significantly predicting incident histologic HSIL within 12 months in models adjusted for HIV status and low-grade squamous intraepithelial lesions at baseline.

Conclusions/Significance

Countries with a high HIV prevalence among MSM and limited HRA resources may consider using biomarkers to identify individuals at high risk of HSIL. E6/E7 mRNA had the highest sensitivity for prevalent HSIL detection regardless of HIV status, whereas type 16 and/or 18 HPV DNA performed best in predicting development of incident HSIL within 12 months.

Anal human papillomavirus infection among HIV-infected and uninfected men who have sex with men in Beijing, China

BACKGROUND

In light of China's unique ethnic and sociocultural context, and a marked rise in HIV prevalence among MSM, it is important to determine prevalence, genotypes and predictors of anal human papillomavirus (HPV) among HIV-infected and uninfected men who have sex with men (MSM) in Beijing, China.

METHODS

In 2010-2011, we recruited MSM (age range 18-61; median 28 years) through peer volunteers, and collected demographic/behavioral information via interviewer-administrated questionnaires. Trained health workers collected anal swabs for HPV genotyping by PCR and blood samples for HIV/syphilis serologies.

RESULTS

We obtained anal specimens from 212 HIV-infected and 459 HIV-uninfected participants. Among HIV-infected MSM, 82.1% were HPV-infected vs. 57.5% in HIV-uninfected (p<0.01). HIV-infected men had the greatest likelihood of multiple types: 17.9% uninfected; 36.3% with one type; 36.8% with 2-3; 9.0% with ≥4. Oncogenic HPV prevalence was higher among HIV- infected (61.3%) than uninfected participants (39.7%; p<0.01). HIV-uninfected MSM reporting always using condoms during insertive anal intercourse (past 6 months) were less likely to be HPV-infected (OR=0.49, 95%CI: 0.31-0.77). Among HIV-uninfected MSM, HPV infection was associated with unprotected receptive anal intercourse (past 6 months; OR=1.92, 95%CI: 1.19-3.11) and being forced to have sex (previous year; OR=3.32, 95%CI: 1.10-10.0). Multivariable logistic analysis among HIV infected MSM suggested that unprotected oral intercourse (past 6 months) was associated with HPV (adjusted OR=2.12, 95%CI: 1.00-4.48). Syphilis occurred in 55.8% of HIV-infected/HPV-infected, 50.0% of HIV-infected/HPV-uninfected, 19.6% of HIV-uninfected/HPV-infected, and 13.0% of HIV-uninfected/HPV-uninfected MSM.

CONCLUSIONS

HPV anal infections were more common among HIV-infected than uninfected MSM in China, including oncogenic and multiple types. Unprotected oral and receptive anal sex were was independently associated with HPV infection. Promotion of safer sex and HPV vaccination is strongly recommended among MSM.

Distribution of human papillomavirus genotypes, assessment of HPV 16 and 18 viral load and anal related lesions in HIV positive patients: a cross-sectional analysis

Natural history of anal intraepithelial neoplasia and anal cancer is not fully understood. Factors associated with cytological abnormalities and predictors of progression to high-grade anal intraepithelial neoplasia still deserve investigation. The aim of this cross-sectional study was to assess the prevalence of HPV types, the relationship between HPV genotypes, HPV 16/18 viral load and cytological abnormalities in male and female HIV-infected patients. One hundred and twenty-two (72.6%) patients were infected with HPV, 75 (61%) had multiple HPV infection, and 94 (77%) had high-risk HPV infection. The most frequently identified HPV types were HPV 16 (64%), HPV 6 (39%), HPV 18 (31%), HPV 53 (14.7%), HPV 33 (10.6%), HPV 11 (8.2%), HPV 70 (5.7%), and HPV 61 (4.9%). The HPV types which were most frequently found in combination were HPV 6 + 16 (9.8%), 6 + 16 + 18 (8.2%), 16 + 18 (6.6%), 6 + 18 (4.9%), 16 + 33 (3.3%), 16 + 53 (3.3%). Median HPV16 and 18 viral loads were 6.1 log10 copies/10(6) cells [IQR 5.0-7.3] and 6.1 log10 copies/10(6) cells [IQR 5.7-6.0], respectively. Male gender (P = 0.03, OR: 1.2 [1.0-1.4]) and homo/bisexual transmission routes (P = 0.044, OR: 1.4 [1.0-1.9]) were associated with HPV 16 infection. An HPV 16 viral load cut-off ≥5.3 log10 copies/10(6) cells and a CD4+ cell count ≤200/µl were independent factors associated with abnormal cytology. In the absence of national consensus guidelines, a strict regular follow-up at shorter intervals is recommended for HIV-infected patients with abnormal cytology, especially low grade squamous intraepithelial lesions, an HPV 16 viral load ≥5.3 log/10(6) cells and a CD4+ cell count ≤200/µl.

NFX1-123 and human papillomavirus 16E6 increase Notch expression in keratinocytes

The high-risk human papillomavirus (HR HPV) E6 oncoprotein binds host cell proteins to dysregulate multiple regulatory pathways, including apoptosis and senescence. HR HPV16 E6 (16E6) interacts with the cellular protein NFX1-123, and together they posttranscriptionally increase hTERT expression, the catalytic subunit of telomerase. NFX1-123 interacts with hTERT mRNA and stabilizes it, leading to greater telomerase activity and the avoidance of cellular senescence. Little is known regarding what other transcripts are dependent on or augmented by the association of NFX1-123 with 16E6. Microarray analysis revealed enhanced expression of Notch1 mRNA in 16E6-expressing keratinocytes when NFX1-123 was overexpressed. A moderate increase in Notch1 mRNA was seen with overexpression of NFX1-123 alone, but with 16E6 coexpression the increase in Notch1 was enhanced. The PAM2 motif and R3H protein domains in NFX1-123, which were important for increased hTERT expression, were also important in the augmentation of Notch1 expression by 16E6. These findings identify a second gene coregulated by 16E6 and NFX1-123 and the protein motifs in NFX1-123 that are important for this effect.

Trends in the occurrence of high-grade anal intraepithelial neoplasia in San Francisco: 2000-2009

BACKGROUND

Although screening of human immunodeficiency virus (HIV)-positive individuals for anal intraepithelial neoplasia (AIN; a precursor of anal cancer) has been practiced in San Francisco among HIV health care providers since the early 1990s, to the authors' knowledge no study to date has focused on evaluating recent AIN trends.

METHODS

Cases of high-grade AIN 3 and invasive anal cancer from 2000 to 2009 were obtained from the San Francisco/Oakland Surveillance, Epidemiology, and End Results (SEER) population-based cancer registry. Age-standardized rates of AIN 3 and anal cancer were calculated overall and by demographic characteristics (sex, race, and age group). Log-linear regression calculated annual percent change in rates during 2000 to 2009, and rate ratios (RRs) and 95% confidence intervals (95% CIs), evaluated differences in rates during 2000 through 2004 and 2005 through 2009.

RESULTS

During 2000 through 2009, the majority of AIN 3 cases occurred among men (1152 of 1320 men; 87.3%). Rates of AIN 3 during the corresponding period increased by 11.48% per year (P < .05) among men and were stable among women. Comparing rates among men during 2000 to 2004 with those during 2005 to 2009, the largest increases were noted among those aged 50 years to 64 years (RR, 2.47; 95% CI, 1.93-3.17) and among black individuals (RR, 3.49; 95% CI, 2.14-5.85). During the same period, anal cancer rates were stable among men and women.

CONCLUSIONS

Rates of AIN 3 increased in San Francisco during 2000 through 2009, in conjunction with an anal cytology screening program for high-risk groups, whereas rates of invasive anal cancer were unchanged. Continued surveillance is necessary to evaluate the impact of screening and human papillomavirus vaccination on the prevention of human papillomavirus-related AIN and anal cancer.

Epidemiology, natural history and risk factors for anal intraepithelial neoplasia

Studies conducted in HIV-seropositive individuals have enhanced our understanding of the natural history of anal intraepithelial neoplasia (AIN) and of factors predictive of progression to high-grade AIN, the immediate precursor to anal cancer. AIN is frequently detected in HIV-seropositive individuals. Factors that increase the risk for AIN include HIV infection, low current or nadir blood CD4+ cell counts, receptive anal intercourse, oncogenic human papillomavirus (HPV) infection, persistent anal HPV infection, multiple HPV type infections and high anal HPV viral load. This review confirms the importance of high-grade AIN in HIV-seropositive individuals and HIV-seronegative men having sex with men.

Prevalence and predictors of high-grade anal intraepithelial neoplasia in a community-based sample of homosexual men

BACKGROUND

We report the prevalence and predictors for high-grade anal intraepithelial neoplasia (HGAIN) in community-based cohorts of HIV-negative and HIV-positive homosexual men in Sydney, Australia.

METHODS

A cross-sectional study of consecutive participants in both cohorts was performed in 2005 (204 HIV-negative and 128 HIV-positive men). Anal swabs collected by a research nurse underwent cytological analysis, using the ThinPrep procedure, and human papillomavirus (HPV) testing. Participants who had cytological abnormalities other than low-grade squamous epithelial lesions (SIL) were referred for high resolution anoscopy (HRA).

RESULTS

A total of 114 men had cytological abnormalities (24.3% of HIV-negative and 57.5% of HIV-positive men, odds ratio (OR)=4.21, 95% confidence interval (CI) 2.57-6.90). However, only three (2.3%) HIV-positive men and no HIV-negative men had high-grade SIL on anal cytology. Seventy-seven men were referred for HRA, of whom 63 (81.8%) attended. Histologically confirmed HGAIN was detected in 21 (33.3%). The prevalence of HGAIN was higher in HIV-positive men (10.8%) than in HIV-negative men (5.0%, OR=2.29, 95% CI 0.93-5.63, P=0.071). HGAIN was not related to age but was strongly associated with the detection of high-risk types of anal HPV (OR=10.1, 95% CI 1.33-76.2) rather than low-risk types (OR=1.97, 95% CI 0.74-5.25).

CONCLUSION

HGAIN was prevalent in homosexual men across all age groups and was more than twice as common in HIV-positive men compared with HIV-negative men. The presence of high-risk anal HPV was highly predictive of HGAIN.

A comparison of human papillomavirus genotype-specific DNA and E6/E7 mRNA detection to identify anal precancer among HIV-infected men who have sex with men

BACKGROUND

Human papillomavirus (HPV) RNA detection is reportedly more specific for the detection of anogenital precancer than HPV DNA but it is unknown whether this is due to detection of RNA or due to HPV genotype restriction.

METHODS

A total of 363 human immunodeficiency virus (HIV)-positive men who have sex with men had two anal cytology samples taken and were evaluated using high-resolution anoscopy and biopsies of visible lesions. Anal specimens were tested for E6/E7 RNA for five carcinogenic HPV genotypes (HPV16, 18, 31, 33, and 45) and tested for the DNA of 13 carcinogenic HPV genotypes.

RESULTS

DNA testing was more likely to be positive than RNA testing (53% vs. 48%; P = 0.02) for the same five HPV genotypes in aggregate. When restricted to five HPV genotypes targeted by the RNA test, the sensitivity to detect anal precancer was the same for DNA and RNA (81%), whereas RNA was more specific than DNA (65% vs. 58%; P = 0.007). In comparison, DNA detection of all 13 carcinogenic HPV genotypes was more sensitive (96% vs. 81%; P = 0.001) but much less specific (65% vs. 33%; P < 0.001) as compared with RNA detection of the five HPV genotypes.

CONCLUSION

After controlling for HPV genotypes, RNA was only slightly more specific than DNA detection for anal precancer.

IMPACT

DNA or RNA testing for a subset of the most carcinogenic HPV genotypes may be useful for distinguishing between those HPV-positive men at higher and lower risk of anal precancer and cancer.

[CD4 lymphocytes as a protective factor against infection by oncogenic genotypes of human papillomavirus in the anal mucosa of men who have sex with human immunodeficiency virus positive men]

BACKGROUND AND OBJECTIVES

To analyze the prevalence of human papillomavirus (HPV) genotypes and anal dysplasia in a cohort of human immunodeficiency virus (HIV) infected men who have sex with men (MSM) from southern Spain, and the variables associated with the appearance of dysplastic lesions and oncogenic HPV genotypes.

PATIENTS AND METHODS

A cross-sectional study involving a prospective cohort of HIV-positive MSM included consecutively after signing an informed consent form. During the consultation 2 samples were taken from the anal mucosa: one for HPV detection using polymerase chain reaction (PCR), and the other for cytological evaluation; the Bethesda system was used to classify the cytology.

RESULTS

One hundred and thirty-four consecutive patients were included. 91.1% patients were colonized by HPV, 66.1% by high-grade types and 41.52% by genotypes of low and high-grade malignancy. The most prevalent genotypes were: 6, 11, 16, 18, 51 and 53. 72.2% samples sent for cytology showed dysplasia, of which 71.4% were low-grade squamous intraepithelial lesions, 23.1% were atypical squamous cell, and 0% was high-grade squamous intraepithelial lesions. The multivariate analysis of risk factors associated with the appearance of dysplasia revealed association with smoking (95% confidence interval [95% CI] 1.196-9.303; odds ratio [OR] 3.336; P=.02) and number of oncogenic HPV types (95% CI 1.387-3.811; OR 2.229; P=.001). With regard to the presence of oncogenic HPV genotypes the multivariate analysis showed a high CD4 cell count was a protective factor against infection by these viruses (95% CI 1.098-5.58; OR 2.48; P=.029).

CONCLUSIONS

The prevalence of anal dysplasia among HIV-positive MSM in this study is very high, fundamentally in smokers and a high number of oncogenic HPV genotypes. The presence of oncogenic HPV genotypes was associated with a lower CD4 cell count.

Ano-genital human papillomavirus type 97 infection is detected in Canadian men but not women at risk or infected with the human immunodeficiency virus

Background

Human papillomavirus type 97 (HPV97) DNA was detected in nearly 5% of anal samples collected from HIV-seropositive men living in Montreal, Canada. The rate of detection of HPV97 in the genital tract of Canadian women is unknown. Whether HPV97 is a local epidemic in HIV-seropositive men living in Montreal is also unknown. The prevalence of human papillomavirus type 97 (HPV97) was assessed in cervicovaginal cells from women living in Canada and in anal samples from HIV-seropositive men living in Toronto.

Findings

Cervicovaginal lavages collected from 904 women (678 HIV-seropositive, 226 HIV-seronegative) women living in Canada and anal cells collected from 123 HIV-seropositive men living in Toronto were tested for the presence of HPV97 with PCR. HPV97-positive samples were further tested by PCR-sequencing for molecular variant analysis to assess if all HPV97-positive men were infected with the same strain. All cervicovaginal samples were negative for HPV97. HPV97 was detected in anal samples from 6 HIV-seropositive men (4.9%, 95% confidence interval 2.0-10.5%), of whom five had high-grade and one had low-grade anal intraepithelial neoplasia, in addition to 2 to 8 HPV genital genotypes per sample. Four HPV97 variants were defined by four variation sites in the viral control region.

Conclusion

These findings indicate that HPV97 infects in the anal canal of HIV-seropositive men but is not detected in the genital tract of women.

Anal cytological abnormalities and epidemiological correlates among men who have sex with men at risk for HIV-1 infection

Background

The incidence of anal cancer, a Human Papillomavirus (HPV)-related neoplasia, has been increasing in recent decades, mainly in men who have sex with men (MSM). Cytological changes of the anal epithelium induced by HPV can be detected through an anal pap smear. This study aimed to evaluate the prevalence and epidemiological correlates of anal cytological abnormalities among relatively young MSM at risk for HIV-1 infection, to help clarify whether or not this population deserves further investigation to assess the presence of anal cancer precursor lesions.

Methods

MSM were recruited among attendees of a large STI clinic for a HIV-1 screening program. Anal samples, collected with a Dracon swab in PreservCyt, were used both for liquid-based cytology and HPV testing by the Linear Array HPV Genotyping Test. Data regarding socio-demographic characteristics and sexual behavior were collected in face-to-face interviews.

Results

A total of 346 MSM were recruited (median age 32 years). Overall, 72.5% of the individuals had an anal HPV infection, with 56.1% of them being infected by oncogenic HPV genotypes. Anal cytological abnormalities were found in 29.8% of the cases (16.7% ASC-US and 13.1% L-SIL). Presence of ASC-US+ was strongly associated with infection by any HPV type (OR=4.21, 95% CI: 1.97-9.23), and particularly by HPV 16 and/or 18 (OR=5.62, 95% CI: 2.33-13.81). A higher proportion of ASC-US+ was found in older MSM, in those with a higher number of lifetime partners and in those with a history of ano-genital warts. However, none of these variables or the others analyzed showed any significant association with abnormal cytological findings.

Conclusions

The presence of anal cytological abnormalities in about one third of the recruited MSM and their strong association with HPV infection, in particular that caused by HPV 16 and/or 18, might provide a further complement to the data that now support the introduction of HPV vaccination among MSM to protect them from the development of HPV-associated diseases. Additional studies are needed to determine whether and how screening for anal cancer precursor lesions should be performed in younger MSM.

Use of highly active antiretroviral therapy is associated with lower prevalence of anal intraepithelial neoplastic lesions and lower prevalence of human papillomavirus in HIV-infected men who have sex with men

BACKGROUND

The incidence of anal intraepithelial neoplasia (AIN) and anal cancer is increased in HIV-positive men who have sex with men (MSM). Persistent high-risk human papillomavirus (HPV) infection is an important etiologic agent.

METHODS

In this study, a group of 250 HIV-positive MSM was included to determine the prevalence of AIN and to investigate the role of highly active antiretroviral therapy (HAART), high-risk HPV, and other risk factors possibly associated with this prevalence.

RESULTS

Among patients included, 108 (43.2%) had lesions suspicious for AIN. Histologic analyses showed AIN 1 in 24 patients (22.2%), AIN 2 in 6 patients (5.6%), and AIN 3 in 10 patients (9.3%). In multivariable analyses, the use of HAART was associated with the absence of AIN (P = 0.045). In MSM without HAART, HPV infection was detected significantly more often compared with those who used HAART (P = 0.010). AIN was associated with HPV types 16 and 6.

CONCLUSIONS

In this cross-sectional study in 250 HIV-positive MSM, the use of HAART was associated with lower prevalence of AIN and a significantly lower prevalence of HPV. This association between the prevalence of AIN and the absence of HAART may contribute to the current debate on when to start HAART in HIV-infected individuals.

Assessing urine human papillomavirus polymerase chain reaction testing as a tool for screening anal HPV infection in HIV-positive MSM

Multiple types of human papillomavirus (HPV) are responsible for most cervical cancers but also cause anal cancers-especially in HIV-positive patients. Furthermore, men who have sex with men (MSM) are twice as likely to develop anal cancers as non-MSM. A simple screening test for HPV infection would be useful in these patients. The aim of our study was to evaluate the detection of HPV by real-time polymerase chain reaction (PCR) in urine as a marker of anal infection in MSM. The study included 52 HIV-positive MSM treated at Amiens University Hospital (Amiens, France). After obtaining informed consent, we performed an anal swab and gathered 10 mL of first-void urine. Samples were extracted and amplified in a real-time PCR. Genotypes were determined with a PapilloCheck(®) system (Greiner Bio-One, Frickenhausen, Germany). The anal test was the gold standard for calculating the characteristics of the urine test. The sensitivity of the urine test for diagnosing anal HPV infection was 15%, the specificity was 66%, the positive predictive value was 87.5%, and negative predictive value was 4.5%. The prevalence of anal HPV infection in the study population was 94%. Genotype 42 was the most common. The anal HPV viral load was significantly lower in men in a stable relationship than in single men. However, there was no statistically significant relationship between anal viral load and anal intraepithelial lesions. We conclude that urine-based HPV is a poor predictor of anal HPV infection in HIV-positive MSM.

Anal human papillomavirus infection and associated neoplastic lesions in men who have sex with men: a systematic review and meta-analysis

BACKGROUND

Men who have sex with men (MSM) are at greatly increased risk of human papillomavirus (HPV)-associated anal cancer. Screening for the presumed cancer precursor, high-grade anal intraepithelial neoplasia (AIN), followed by treatment in a manner analogous to cervical screening, has been proposed. We aimed to assess available data for anal HPV disease that can inform pre-cancer screening programmes.

METHODS

We searched PubMed, OVID Medline, and Embase for all studies published before Nov 1, 2011, that reported prevalence and incidence of anal HPV detection, AIN, and anal cancer in MSM. We calculated summary estimates using random-effects meta-analysis.

FINDINGS

53 studies met the inclusion criteria, including 31 estimates of HPV prevalence, 19 estimates of cytological abnormalities, eight estimates of histological abnormalities, and nine estimates of anal cancer incidence. Data for incident HPV and high-grade AIN were scarce. In HIV-positive men, the pooled prevalence of anal HPV-16 was 35·4% (95% CI 32·9-37·9). In the only published estimate, incidence of anal HPV-16 was 13·0% (9·6-17·6), and clearance occurred in 14·6% (10·2-21·2) of men per year. The pooled prevalence of histological high-grade AIN was 29·1% (22·8-35·4) with incidences of 8·5% (6·9-10·4) and 15·4% (11·8-19·8) per year in two estimates. The pooled anal cancer incidence was 45·9 per 100,000 men (31·2-60·3). In HIV-negative men, the pooled prevalence of anal HPV-16 was 12·5% (9·8-15·4). Incidence of HPV-16 was 11·8% (9·2-14·9) and 5·8% (1·9-13·5) of men per year in two estimates. The pooled prevalence of histological high-grade AIN was 21·5% (13·7-29·3), with incidence of 3·3% (2·2-4·7) and 6·0% (4·2-8·1) per year in two estimates. Anal cancer incidence was 5·1 per 100,000 men (0-11·5; based on two estimates). There were no published estimates of high-grade AIN regression.

INTERPRETATION

Anal HPV and anal cancer precursors were very common in MSM. However, on the basis of restricted data, rates of progression to cancer seem to be substantially lower than they are for cervical pre-cancerous lesions. Large, good-quality prospective studies are needed to inform the development of anal cancer screening guidelines for MSM.

FUNDING

Australian Government Department of Health and Ageing.

No evidence for human papillomavirus in the etiology of colorectal polyps

BACKGROUND

While some studies have reported detection of oncogenic human papillomavirus (HPV) in colorectal tumors, others have not.

METHODS

We examined the association between oncogenic HPV infection and colorectal polyps in a case-control study of individuals with colorectal adenomas (n = 167), hyperplastic polyps (n = 87), and polyp-free controls (n = 250). We carried out real-time PCR for HPV-16 and -18 DNA, and SPF PCR covering 43 HPV types, on lesional and normal colorectal tissue samples. Plasma antibodies for oncogenic HPV types were assessed via a bead-based multiplex Luminex assay.

RESULTS

HPV DNA was not found in any of the 609 successfully assayed colorectal tissue samples from adenomas, hyperplastic polyps, normal biopsies adjacent to polyps, or normal biopsies of the rectum of disease-free controls. Also, there was no association between HPV seropositivity for all oncogenic HPV types combined, for either polyp type, and for men or women. When analyses were restricted to participants without a history of polyps, among men [adenomas (n = 31), hyperplastic polyps (n = 28), and controls (n = 68)], there was an association between seropositivity and hyperplastic polyps when all oncogenic HPV types were combined (OR = 3.0; 95% CI: 1.1-7.9).

CONCLUSIONS

Overall, our findings do not support an etiologic relationship between HPV and colorectal adenomas or hyperplastic polyps; however, our finding suggesting an association between HPV seropositivity and hyperplastic polyps in men may warrant further investigations.

IMPACT

After stringent controls for contamination and three methods to assess HPV infection, we report no evidence for HPV in the etiology of colorectal neoplasia for either men or women.

The handling of missing data in molecular epidemiology studies

Molecular epidemiology studies face a missing data problem, as biospecimen or imaging data are often collected on only a proportion of subjects eligible for study. We investigated all molecular epidemiology studies published as Research Articles, Short Communications, or Null Results in Brief in Cancer Epidemiology, Biomarkers & Prevention from January 1, 2009, to March 31, 2010, to characterize the extent that missing data were present and to elucidate how the issue was addressed. Of 278 molecular epidemiology studies assessed, most (95%) had missing data on a key variable (66%) and/or used availability of data (often, but not always the biomarker data) as inclusion criterion for study entry (45%). Despite this, only 10% compared subjects included in the analysis with those excluded from the analysis and 88% with missing data conducted a complete-case analysis, a method known to yield biased and inefficient estimates when the data are not missing completely at random. Our findings provide evidence that missing data methods are underutilized in molecular epidemiology studies, which may deleteriously affect the interpretation of results. We provide practical guidelines for the analysis and interpretation of molecular epidemiology studies with missing data.

Age-specific prevalence of human papillomavirus infection in males: a global review

PURPOSE

Global data on age-specific prevalence of human papillomavirus (HPV) infection in males, especially for oncogenic HPV types 16 and 18, are essential for future efforts to prevent HPV-related diseases, including expanded access to HPV prophylactic vaccines for boys and young men.

METHODS

A systematic review of peer-reviewed publications was conducted to summarize worldwide data on genital HPV-DNA prevalence in men. Studies using polymerase chain reaction or hybrid capture detection assays were included.

RESULTS

Approximately 6,600 abstracts were identified. Of them, 64 reported age-specific HPV prevalence and were included in the review. Of these, 38 were from populations at high risk of HPV infections, such as sexually transmitted infection clinic attendees, human immunodeficiency virus-positive males, and male partners of women with HPV infection or abnormal cytology. The largest proportions of studies were from Europe (38%) and North America (25%), with smaller proportions from Central and South America (19%), Asia (11%), and Africa (5%). Across all regions, data on HPV prevalence were generally limited to men >18 years of age. HPV prevalence was high among sexually active men in all regions but with considerable variation, from 1% to 84% among low-risk men and from 2% to 93% among high-risk men. Peak HPV prevalence spanned a wide range of ages and was generally not concentrated in the younger age groups. Age-specific prevalence curves were relatively flat or declined only slightly following peak prevalence.

CONCLUSIONS

Genital HPV infection in men varies widely, both between and within high- and low-risk groups and by geographic region. Compared with that in women, HPV prevalence in men seems to peak at slightly older ages and remains constant or decreases slightly with increasing age, suggesting persistent HPV infection or a higher rate of reinfection.

Anal HPV infection in HIV-positive men who have sex with men from China

Background

Anal HPV infection, which contributes to the development of anal warts and anal cancer, is well known to be common among men who have sex with men (MSM), especially among those HIV positives. However, HIV and anal HPV co-infection among MSM has not been addressed in China.

Methods

A cross-sectional study was conducted in Beijing and Tianjin, China. Study participants were recruited using multiple methods with the collaboration of local volunteer organizations. Blood and anal swabs were collected for HIV-1 serological test and HPV genotyping.

Results

A total of 602 MSM were recruited and laboratory data were available for 578 of them (96.0%). HIV and anal HPV prevalence were 8.5% and 62.1%, respectively. And 48 MSM (8.3%) were found to be co-infected. The HPV genotypes identified most frequently were HPV06 (19.6%), HPV16 (13.0%), HPV52 (8.5%) and HPV11 (7.6%). Different modes of HPV genotypes distribution were observed with respect to HIV status. A strong dose-response relationship was found between HIV seropositivity and multiplicity of HPV genotypes (p<0.001), which is consistent with the observation that anal HPV infection was an independent predictor for HIV infection.

Conclusions

A high prevalence of HIV and anal HPV co-infection was observed in the MSM community in Beijing and Tianjin, China. Anal HPV infection was found to be independently associated with increased HIV seropositivity, which suggests the application of HPV vaccine might be a potential strategy to reduce the acquisition of HIV infection though controlling the prevalence of HPV.

Episomal and integrated human papillomavirus type 16 loads and anal intraepithelial neoplasia in HIV-seropositive men

OBJECTIVES

To assess levels of episomal and integrated human papillomavirus type 16 (HPV-16) loads in HIV-seropositive men who have sex with men (MSM) in anal infection and to study the association between episomal and integrated HPV-16 loads and anal intraepithelial neoplasia (AIN).

STUDY DESIGN

A cohort study of 247 HIV-positive MSM followed each 6 months for 3 years. Overall, 135 (54.7%) men provided 665 HPV-16-positive anal samples.

METHODS

Episomal and integrated HPV-16 loads were measured with quantitative real-time PCR assays. HPV-16 integration was confirmed in samples with a HPV-16 E6/E2 of 1.5 or more with PCR sequencing to demonstrate the presence of viral-cellular junctions.

RESULTS

The HPV-16 DNA forms in anal samples were characterized as episomal only in 627 samples (94.3%), mixed in 22 samples (3.3%) and integrated only in nine samples (1.4%). HPV-16 episomal load [odds ratio (OR) = 1.5, 95% confidence interval (CI) 1.1-2.1], number of HPV types (OR = 1.4, 95% CI 1.1-1.8) and current smoking (OR = 4.8, 95% CI 1.3-18.6) were associated with high-grade AIN (AIN-2,3) after adjusting for age and CD4 cell counts. Integrated HPV-16 load was not associated with AIN-2,3 (OR = 0.7, 95% CI 0.4-1.1). Considering men with AIN-1 at baseline, four (16.7%) of the 24 men who progressed to AIN-2,3 had at least one sample with integrated HPV-16 DNA compared with three (23.1%) of 13 men who did not progress (OR = 0.7, 95% CI 0.2-3.8; P = 0.64). Integration was detected in similar proportions in samples from men without AIN, with AIN-1 or AIN-2,3.

CONCLUSION

High episomal HPV-16 load but not HPV-16 integration load measured by real-time PCR was associated with AIN-2,3.