Staci L. Sudenga

EUROGIN 2014 roadmap: Differences in human papillomavirus infection natural history, transmission and human papillomavirus-related cancer incidence by gender and anatomic site of infection

Human papillomaviruses (HPVs) cause cancer at multiple anatomic sites in men and women, including cervical, oropharyngeal, anal, vulvar and vaginal cancers in women and oropharyngeal, anal and penile cancers in men. In this EUROGIN 2014 roadmap, differences in HPV‐related cancer and infection burden by gender and anatomic site are reviewed. The proportion of cancers attributable to HPV varies by anatomic site, with nearly 100% of cervical, 88% of anal and <50% of lower genital tract and oropharyngeal cancers attributable to HPV, depending on world region and prevalence of tobacco use. Often, mirroring cancer incidence rates, HPV prevalence and infection natural history varies by gender and anatomic site of infection. Oral HPV infection is rare and significantly differs by gender; yet, HPV‐related cancer incidence at this site is several‐fold higher than at either the anal canal or the penile epithelium. HPV seroprevalence is significantly higher among women compared to men, likely explaining the differences in age‐specific HPV prevalence and incidence patterns observed by gender. Correspondingly, among heterosexual partners, HPV transmission appears higher from women to men. More research is needed to characterize HPV natural history at each anatomic site where HPV causes cancer in men and women, information that is critical to inform the basic science of HPV natural history and the development of future infection and cancer prevention efforts.

Alternative dosage schedules with HPV virus-like particle vaccines

HPV vaccines can prevent multiple cancers in women and men. Difficulties in the cost and completion of the three-dose vaccine series have led to considerations of alternative dose schedules. In clinical trials, three doses given within a 12-month period versus the standard 6-month period yielded comparable results, and immunogenicity appears comparable with two doses in adolescent females compared to the three-dose series in adult females. While the data are generally supportive of moving to a two-dose vaccine schedule among young female adolescents, the adoption of a two-dose vaccine schedule still poses a potential risk to the strength and longevity of the immune response. Public health authorities implementing a two-dose vaccine schedule should devise risk management strategies to minimize the potential impact on cancer prevention.

Knowledge, attitudes, practices, and perceived risk of cervical cancer among kenyan women brief report

Objectives Eastern Africa has the highest incidence and mortality rates from cervical cancer worldwide. It is important to describe the differences among women and their perceived risk of cervical cancer to determine target groups to increase cervical cancer screening. Methods In this cross-sectional study, we surveyed women seeking reproductive health services in Kisumu, Kenya to assess their perceived risk of cervical cancer and risk factors influencing cervical cancer screening uptake. χ2 statistics and t tests were used to determine significant factors, which were incorporated into a logistic model to determine factors independently associated with cervical cancer risk perception. Results Whereas 91% of the surveyed women had heard of cancer, only 29% of the 388 surveyed women had previously heard of cervical cancer. Most had received their information from health care workers. Few women (6%) had ever been screened for cervical cancer and cited barriers such as fear, time, and lack of knowledge about cervical cancer. Nearly all previously screened women (22/24 [92%]) believed that cervical cancer was curable if detected early and that screening should be conducted annually (86%). Most women (254/388 [65%]) felt they were at risk for cervical cancer. Women with perceived risk of cervical cancer were older (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02–1.10), reported a history of marriage (OR, 2.08; CI, 1.00–4.30), were less likely to feel adequately informed about cervical cancer by health care providers (OR, 0.76; CI, 0.18–0.83), and more likely to intend to have cervical cancer screening in the future (OR, 10.59; CI, 3.96–28.30). Only 5% of the women reported that they would not be willing to undergo screening regardless of cost. Conclusions Cervical cancer is a major health burden for women in sub-Saharan Africa, yet only one third of the women had ever heard of cervical cancer in Kisumu, Kenya. Understanding factors associated with women’s perceived risk of cervical cancer could guide future educational and clinical interventions to increase cervical cancer screening.

The impact of highly active antiretroviral therapy on prevalence and incidence of cervical human papillomavirus infections in HIV-positive adolescents

BackgroundThe implementation of highly active antiretroviral therapy (HAART) among HIV-positive patients results in immune reconstitution, slower progression of HIV disease, and a decrease in the occurrence of opportunistic infections. However, the impact of HAART on cervical human papillomavirus (HPV) infection, clearance, and persistence in high-risk adolescents remains controversial.MethodsHIV-positive and high-risk HIV-negative female adolescents were enrolled in the Reaching for Excellence in Adolescent Care and Health (REACH) longitudinal cohort study. At each semi-annual clinical visit, cervical lavage samples were tested for 30 HPV types. Type-specific and carcinogenic risk-specific HPV prevalence and incidence were compared in 373 eligible participants: 146 HIV-negative female adolescents with a median follow-up of 721.5 [IQR: 483-1301] days and 227 HIV-positive female adolescents. Of the 227 HIV-positive participants, a fixed set (n = 100) were examined both before and after HAART initiation; 70 were examined only before HAART initiation; and 57 were examined only after HAART initiation, with overall median follow-up of 271 [IQR: 86.5-473] and 427.25 [IQR: 200-871] days respectively for before and after HAART initiation.ResultsOf the 373 eligible participants, 262 (70%) were infected with at least one type of HPV at baseline, and 78 of the remaining 111 (70%) became infected with at least one type of HPV by the end of the study. Overall, the incidence and prevalence of HPV types 58, 53/66, 68/70, and 31/33/35 were much higher than the established carcinogenic and HPV vaccine types 16 and 18, especially in HIV-positive females both before and after HAART initiation. Baseline prevalence for individual high-risk HPV types ranged, depending on type, from 0.7-10%, 1-17%, and 1-18% in the HIV-negative group, the HIV-positive before HAART initiation group, and the HIV-positive after HAART initiation group, respectively. Likewise, the incidence ranged, depending on HPV type, from 0.64-9.83 cases/100 PY, 3.00-12.80 cases/100 PY, and 1.49-17.05 cases/100 PY in the three groups, respectively. The patterns of each HPV type infection, clearance, and persistence did not differ considerably before or after the introduction of HAART and were clearly independent of CD4+ change within the short post-HAART follow-up period.ConclusionsHAART did not immediately affect the incidence of type-specific HPV infections within a short-period follow-up; however, future studies are warranted in larger populations to evaluate HAARTs impact over longer periods.

Seroconversion following anal and genital HPV infection in men: The HIM study

Background Protection from naturally acquired human papillomavirus (HPV) antibodies may influence HPV infection across the lifespan. This study describes seroconversion rates following genital, anal, and oral HPV 6/11/16/18 infections in men and examines differences by HPV type and anatomic site. Methods Men with HPV 6/11/16/18 infections who were seronegative for those genotypes at the time of DNA detection were selected from the HPV Infection in Men (HIM) Study. Sera specimens collected ≤36 months after detection were analyzed for HPV 6/11/16/18 antibodies using a virus-like particle-based ELISA. Time to seroconversion was separately assessed for each anatomic site, stratified by HPV type. Results Seroconversion to ≥1 HPV type (6/11/16/18) in this sub-cohort (N=384) varied by anatomic site, with 6.3%, 18.9%, and 0.0% seroconverting following anal, genital, and oral HPV infection, respectively. Regardless of anatomic site, seroconversion was highest for HPV 6 (19.3%). Overall, seroconversion was highest following anal HPV 6 infection (69.2%). HPV persistence was the only factor found to influence seroconversion. Conclusions Low seroconversion rates following HPV infection leave men susceptible to recurrent infections that can progress to HPV-related cancers. This emphasizes the need for HPV vaccination in men to ensure immune protection against new HPV infections and subsequent disease.

High HIV, HPV, and STI prevalence among young Western Cape, South African women: EVRI HIV prevention preparedness trial.

Background:This study sought to assess the feasibility of conducting a phase III HIV prevention trial using a multivalent human papillomavirus (HPV) vaccine (Gardasil; Merck, Whitehouse Station, NJ). Methods:A total of 479 sexually active women aged 16–24 years in the Western Cape, South Africa, were enrolled in the Efficacy of HPV Vaccine to Reduce HIV Infection (EVRI) Trial. Of these, 402 were HIV negative, nonpregnant, and randomized 1:1 to receive Gardasil or a saline placebo vaccine. Vaccine doses were administered at enrollment, month 2, and month 6, and participants were followed for 1 month after the third dose. Enrollment HIV, HPV, other sexually transmitted infections (STIs), and cervical cytology were evaluated. Rates of accrual, vaccine compliance, and adherence to protocol were monitored. Results:High rates of accrual of eligible females to study (93%) and completion of the 3-dose vaccine series (91%) were noted, with few protocol violations. Ineligibility due to reported HIV positivity was 19%, and another 12% of those enrolled tested HIV positive. STI prevalence was high, with 6.2%, 10.9%, and 32.8% testing positive for syphilis, gonorrhea, and chlamydia, respectively. Cervical prevalence of ≥1 of 37 HPV types was 71%. STI and HPV prevalence was highest among the youngest women (<19 years). Conclusions:Feasibility (successful accrual, retention, and vaccination) of conducting randomized placebo-controlled trials of HPV vaccines among HIV high-risk women in South Africa was demonstrated. This work demonstrates that phase III HIV prevention trials need to intervene at young ages and screen and treat multiple STIs concurrently to have a measurable impact on HIV acquisition.

Genital Human Papillomavirus Infection Progression to External Genital Lesions: The HIM Study

BACKGROUND Human papillomavirus (HPV) causes two types of external genital lesions (EGLs) in men: genital warts (condyloma) and penile intraepithelial neoplasia (PeIN). OBJECTIVE The purpose of this study was to describe genital HPV progression to a histopathologically confirmed HPV-related EGL. DESIGN, SETTING, AND PARTICIPANTS A prospective analysis nested within the HPV Infection in Men (HIM) study was conducted among 3033 men. At each visit, visually distinct EGLs were biopsied; the biopsy specimens were subjected to pathologic evaluation and categorized by pathologic diagnoses. Genital swabs and biopsies were used to identify HPV types using the Linear Array genotyping method for swabs and INNO-LiPA for biopsy specimens. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS EGL incidence was determined among 1788 HPV-positive men, and cumulative incidence rates at 6, 12, and 24 mo were estimated. The proportion of HPV infections that progressed to EGL was also calculated, along with median time to EGL development. RESULTS AND LIMITATIONS Among 1788 HPV-positive men, 92 developed an incident EGL during follow-up (9 PeIN and 86 condyloma). During the first 12 mo of follow-up, 16% of men with a genital HPV 6 infection developed an HPV 6-positive condyloma, and 22% of genital HPV 11 infections progressed to an HPV 11-positive condyloma. During the first 12 mo of follow-up, 0.5% of men with a genital HPV 16 infection developed an HPV 16-positive PeIN. Although we expected PeIN to be a rare event, the sample size for PeIN (n=10) limited the types of analyses that could be performed. CONCLUSIONS Most EGLs develop following infection with HPV 6, 11, or 16, all of which could be prevented with the 4-valent HPV vaccine. PATIENT SUMMARY In this study, we looked at genital human papillomavirus (HPV) infections that can cause lesions in men. The HPV that we detected within the lesions could be prevented by a vaccine.

Key considerations and current perspectives of epidemiological studies on human papillomavirus persistence, the intermediate phenotype to cervical cancer

Persistent infection with human papillomavirus (HPV) causes essentially all precancerous cervical lesions and cervical cancer in females and thus is an important intermediate phenotype to cervical cancer. A majority of infected individuals naturally clear HPV viral infection, but the virus persists in a subset of infected hosts and the mechanism for this differential outcome is not well described. Most of the epidemiological studies have been cross-sectional in nature, and even with longitudinal studies, the definition of HPV persistence or clearance has not been well defined. There is no consensus on the correct time interval between HPV DNA tests, or how to utilize HPV persistence information in clinical management because there is no treatment for HPV. While most studies are performed with the endpoint of cancer, the intermediate phenotype has been overlooked. Epidemiological studies of HPV persistence suffer with several challenges in definitions, study designs, and analyses that undermine its importance in identifying and understanding the interactions between the viral and host genomes in the process of HPV infection pathogenesis. We have evaluated the current status of HPV persistence and provide perspectives on how the field would benefit from a research focus on intermediate phenotype in epidemiological studies.

Diversity of beta-papillomavirus at anogenital and oral anatomic sites of men: The HIM Study

Our goal was to describe prevalence of β-HPVs at three anatomic sites among 717 men from Brazil, Mexico and US enrolled in the HPV Infection in Men (HIM) Study. β-HPVs were genotyped using Luminex technology. Overall, 77.7%, 54.3% and 29.3% men were positive for any β-HPV at the genitals, anal canal, and oral cavity, respectively. Men from US and Brazil were significantly less likely to have β-HPV at the anal canal than men from Mexico. Older men were more likely to have β-HPV at the anal canal compared to younger men. Prevalence of β-HPV at the oral cavity was significantly associated with country of origin and age. Current smokers were significantly less likely to have β-HPV in the oral cavity than men who never smoked. Lack of associations between β-HPV and sexual behaviors may suggest other routes of contact such as autoinoculation which need to be explored further.

Transitional Probability-Based Model for HPV Clearance in HIV-1-Positive Adolescent Females

Background HIV-1-positive patients clear the human papillomavirus (HPV) infection less frequently than HIV-1-negative. Datasets for estimating HPV clearance probability often have irregular measurements of HPV status and risk factors. A new transitional probability-based model for estimation of probability of HPV clearance was developed to fully incorporate information on HIV-1-related clinical data, such as CD4 counts, HIV-1 viral load (VL), highly active antiretroviral therapy (HAART), and risk factors (measured quarterly), and HPV infection status (measured at 6-month intervals). Methodology and Findings Data from 266 HIV-1-positive and 134 at-risk HIV-1-negative adolescent females from the Reaching for Excellence in Adolescent Care and Health (REACH) cohort were used in this study. First, the associations were evaluated using the Cox proportional hazard model, and the variables that demonstrated significant effects on HPV clearance were included in transitional probability models. The new model established the efficacy of CD4 cell counts as a main clearance predictor for all type-specific HPV phylogenetic groups. The 3-month probability of HPV clearance in HIV-1-infected patients significantly increased with increasing CD4 counts for HPV16/16-like (p<0.001), HPV18/18-like (p<0.001), HPV56/56-like (p = 0.05), and low-risk HPV (p<0.001) phylogenetic groups, with the lowest probability found for HPV16/16-like infections (21.60±1.81% at CD4 level 200 cells/mm3, p<0.05; and 28.03±1.47% at CD4 level 500 cells/mm3). HIV-1 VL was a significant predictor for clearance of low-risk HPV infections (p<0.05). HAART (with protease inhibitor) was significant predictor of probability of HPV16 clearance (p<0.05). HPV16/16-like and HPV18/18-like groups showed heterogeneity (p<0.05) in terms of how CD4 counts, HIV VL, and HAART affected probability of clearance of each HPV infection. Conclusions This new model predicts the 3-month probability of HPV infection clearance based on CD4 cell counts and other HIV-1-related clinical measurements.