Joel M. Palefsky

Efficacy of quadrivalent HPV vaccine against HPV Infection and disease in males.

BACKGROUND Infection with human papillomavirus (HPV) and diseases caused by HPV are common in boys and men. We report on the safety of a quadrivalent vaccine (active against HPV types 6, 11, 16, and 18) and on its efficacy in preventing the development of external genital lesions and anogenital HPV infection in boys and men. METHODS We enrolled 4065 healthy boys and men 16 to 26 years of age, from 18 countries in a randomized, placebo-controlled, double-blind trial. The primary efficacy objective was to show that the quadrivalent HPV vaccine reduced the incidence of external genital lesions related to HPV-6, 11, 16, or 18. Efficacy analyses were conducted in a per-protocol population, in which subjects received all three vaccinations and were negative for relevant HPV types at enrollment, and in an intention-to-treat population, in which subjects received vaccine or placebo, regardless of baseline HPV status. RESULTS In the intention-to-treat population, 36 external genital lesions were seen in the vaccine group as compared with 89 in the placebo group, for an observed efficacy of 60.2% (95% confidence interval [CI], 40.8 to 73.8); the efficacy was 65.5% (95% CI, 45.8 to 78.6) for lesions related to HPV-6, 11, 16, or 18. In the per-protocol population, efficacy against lesions related to HPV-6, 11, 16, or 18 was 90.4% (95% CI, 69.2 to 98.1). Efficacy with respect to persistent infection with HPV-6, 11, 16, or 18 and detection of related DNA at any time was 47.8% (95% CI, 36.0 to 57.6) and 27.1% (95% CI, 16.6 to 36.3), respectively, in the intention-to-treat population and 85.6% (97.5% CI, 73.4 to 92.9) and 44.7% (95% CI, 31.5 to 55.6) in the per-protocol population. Injection-site pain was significantly more frequent among subjects receiving quadrivalent HPV vaccine than among those receiving placebo (57% vs. 51%, P<0.001). CONCLUSIONS Quadrivalent HPV vaccine prevents infection with HPV-6, 11, 16, and 18 and the development of related external genital lesions in males 16 to 26 years of age. (Funded by Merck and others; ClinicalTrials.gov number, NCT00090285.).

Prevalence and Risk Factors for Human Papillomavirus Infection of the Anal Canal in Human Immunodeficiency Virus (HIV)-Positive and HIV-Negative Homosexual Men

One of the groups at highest risk of anal cancer is homosexual and bisexual men. Like cervical cancer, anal cancer is associated with human papillomavirus (HPV) infection. Anal HPV infection was characterized in a study of 346 human immunodeficiency virus (HIV)-positive and 262 HIV-negative homosexual and bisexual men. Anal HPV DNA was detected in 93% of HIV-positive and 61% of HIV-negative men by polymerase chain reaction. The spectrum of HPV types was similar in HIV-positive and HIV-negative men, with HPV-16 the most common type. Infection with multiple HPV types was found in 73% of HIV-positive and 23% of HIV-negative men. Among HIV-positive men who were positive by hybrid capture for group B HPV types (16/18/31/33/35/39/45/51/52/56/58) or group A types (6/11/42/43/44), lower CD4 cell levels were associated with higher levels of group B DNA (P = .004) but not group A DNA. These data suggest increased replication of the more oncogenic HPV types with more advanced immunosuppression.

HPV Vaccine against Anal HPV Infection and Anal Intraepithelial Neoplasia

BACKGROUND The rate of anal cancer is increasing among both women and men, particularly men who have sex with men. Caused by infection with human papillomavirus (HPV), primarily HPV type 16 or 18, anal cancer is preceded by high-grade anal intraepithelial neoplasia (grade 2 or 3). We studied the safety and efficacy of quadrivalent HPV vaccine (qHPV) against anal intraepithelial neoplasia associated with HPV-6, 11, 16, or 18 infection in men who have sex with men. METHODS In a substudy of a larger double-blind study, we randomly assigned 602 healthy men who have sex with men, 16 to 26 years of age, to receive either qHPV or placebo. The primary efficacy objective was prevention of anal intraepithelial neoplasia or anal cancer related to infection with HPV-6, 11, 16, or 18. Efficacy analyses were performed in intention-to-treat and per-protocol efficacy populations. The rates of adverse events were documented. RESULTS Efficacy of the qHPV vaccine against anal intraepithelial neoplasia associated with HPV-6, 11, 16, or 18 was 50.3% (95% confidence interval [CI], 25.7 to 67.2) in the intention-to-treat population and 77.5% (95% CI, 39.6 to 93.3) in the per-protocol efficacy population; the corresponding efficacies against anal intraepithelial neoplasia associated with HPV of any type were 25.7% (95% CI, -1.1 to 45.6) and 54.9% (95% CI, 8.4 to 79.1), respectively. Rates of anal intraepithelial neoplasia per 100 person-years were 17.5 in the placebo group and 13.0 in the vaccine group in the intention-to-treat population and 8.9 in the placebo group and 4.0 in the vaccine group in the per-protocol efficacy population. The rate of grade 2 or 3 anal intraepithelial neoplasia related to infection with HPV-6, 11, 16, or 18 was reduced by 54.2% (95% CI, 18.0 to 75.3) in the intention-to-treat population and by 74.9% (95% CI, 8.8 to 95.4) in the per-protocol efficacy population. The corresponding risks of persistent anal infection with HPV-6, 11, 16, or 18 were reduced by 59.4% (95% CI, 43.0 to 71.4) and 94.9% (95% CI, 80.4 to 99.4), respectively. No vaccine-related serious adverse events were reported. CONCLUSIONS Use of the qHPV vaccine reduced the rates of anal intraepithelial neoplasia, including of grade 2 or 3, among men who have sex with men. The vaccine had a favorable safety profile and may help to reduce the risk of anal cancer. (Funded by Merck and the National Institutes of Health; ClinicalTrials.gov number, NCT00090285.).

The natural history of human papillomavirus infection as measured by repeated DNA testing in adolescent and young women

OBJECTIVES The objectives of this study were to describe the early natural history of human papillomavirus (HPV) infection by examining a cohort of young women positive for an HPV test and to define within this cohort (1) the probability of HPV regression, (2) the risk of having a squamous intraepithelial lesion, and (3) factors that were associated with HPV regression. STUDY DESIGN The study was a cohort analytic design. An inception cohort of 618 women positive for HPV participated. HPV testing, cytologic evaluation, and colposcopic evaluation were performed at 4-month intervals. HPV testing was characterized for two groups: low risk (five types rarely associated with cancers) and high risk (nine types most commonly associated with cancers). RESULTS Estimates provided by Kaplan-Meier curves showed that approximately 70% of women were found to have HPV regression by 24 months. Women with low-risk HPV type infections were more likely to show HPV regression than were women with high-risk HPV type infections (log rank test p = 0.002). The relative risk for the development of high-grade squamous intraepithelial lesion (HSIL) was 14.1 (95% confidence interval: 2.3, 84.5) for women with at least three positive tests for high-risk HPV preceding the development of the HSIL compared with that for women with negative tests for high-risk HPV. However, 88% of women with persistent positive HPV tests have not had HSIL to date. No factors associated with high-risk HPV type regression were identified except for a negative association with an incident history of vulvar condyloma (relative risk = 0.5 [95% confidence interval: 0.3 to 0.8]). CONCLUSION Most young women with a positive HPV test will become negative within a 24-month period. Persistent positive tests with oncogenic HPV types represented a significant risk for the development of HSIL. However, we found that most young women with persistent positive HPV tests did not have cytologically perceptible HSIL over a 2-year period. Factors thought to be associated with the development of HSIL were found not to be important in HPV regression.

Anal intraepithelial neoplasia in the highly active antiretroviral therapy era among HIV-positive men who have sex with men.

Objectives:The incidence of anal cancer among men who have sex with men (MSM) has continued to increase since the introduction of highly active antiretroviral therapy (HAART). The prevalence of the putative anal cancer precursor, anal intraepithelial neoplasia (AIN) was high among HIV-positive MSM prior to the availability of HAART but little is known about AIN since HAART was introduced. We characterized the prevalence of AIN among HIV-positive MSM and examined the association between AIN and various factors including use of HAART. Design and methods:A baseline point-prevalence analyses in a prospective cohort study of AIN was performed at a university-based research clinic. A total of 357 HIV-positive MSM with no history of anal cancer completed a questionnaire detailing behaviors and medical history, anal cytology and human papillomavirus (HPV) testing, and high-resolution anoscopy with biopsy for detection of AIN. Results:Eighty-one percent of participants with available CD4+ cell counts at baseline had AIN of any grade; 52% had AIN 2 or 3; and 95% had anal HPV infection. In multivariate analysis, detection of ≥ 6 HPV types [odds ratio (OR), 36; 95% confidence interval (CI), 7.4–171) and use of HAART (OR, 10; 95% CI, 2.6–38) were associated with AIN after adjustment for length of time participants were HIV-positive, CD4+ cell count and HIV viral load. Conclusions:The prevalence of AIN has remained high among HIV-positive MSM after the introduction of HAART. Our data indicate that HAART is not associated with a reduced prevalence of AIN and support measures to prevent anal cancer among HIV-positive MSM whether or not they are using HAART.

High incidence of anal high-grade squamous intra-epithelial lesions among HIV-positive and HIV-negative homosexual and bisexual men.

Objective:The incidence of anal cancer among homosexual men exceeds that of cervical cancer in women, and HIV-positive homosexual men may be at even higher risk than HIV-negative men. Cervical cancer is preceded by high-grade squamous intra-epithelial lesions (HSIL) and anal HSIL may similarly be the precursor to anal cancer. In this study, we describe the incidence of and risk factors for HSIL in HIV-positive and HIV-negative homosexual and bisexual men. Design:Prospective cohort study of HIV-positive and HIV-negative homosexual men. Setting:The University of California, San Francisco. Patients:346 HIV-positive and 262 HIV-negative men enrolled at baseline, 277 HIV-positive and 221 HIV-negative homosexual men followed after baseline. Study design:A questionnaire was administered detailing lifestyle habits, medical history and sexual practices. Anal swabs for cytology and human papillomavirus studies were obtained, followed by biopsies of visible lesions. Human papillomavirus testing was performed using polymerase chain reaction (PCR) and ‘hybrid capture’. Blood was obtained for HIV testing and measurement of CD4 levels. Main outcome measures:Incident HSIL. Results:HIV-positive men were more likely to develop HSIL than HIV-negative men relative risk (RR), 3.7; 95% confidence interval (CI), 2.6–5.7. Life-table estimates of the 4-year incidence of HSIL was 49% (95% CI, 41–56) among HIV-positive men and 17% (95% CI, 12–23) among HIV-negative men. Among HIV-positive men, those with lower baseline CD4 counts (P = 0.007) and persistent infection with one or more human papillomavirus types, determined using PCR (P = 0.0001), were more likely to develop HSIL. Conclusions:HIV infection, lower CD4 levels and human papillomavirus infection were associated with high rates of incident HSIL among homosexual men. However, high rates were found at all CD4 levels among HIV-positive men and among HIV-negative men.

Human papillomavirus type distribution in anal cancer and anal intraepithelial lesions.

A systematic review was conducted of HPV type distribution in anal cancer and anal high‐grade and low‐grade squamous intraepithelial lesions (HSIL and LSIL). A Medline search of studies using PCR or hybrid capture for HPV DNA detection was completed. A total of 1,824 cases were included: 992 invasive anal cancers, 472 HSIL cases and 360 LSIL cases. Crude HPV prevalence in anal cancer, HSIL, and LSIL was 71, 91 and 88%, respectively. HPV16/18 prevalence was 72% in invasive anal cancer, 69% in HSIL and 27% in LSIL. The HPV 16 and/or 18 prevalence in invasive anal cancer cases was similar to that reported in invasive cervical cancer. If ongoing clinical trials show efficacy in preventing anal HPV infection and associated anal lesions, prophylactic HPV vaccines may play an important role for the primary prevention of these cancers in both genders.

Anal cytology as a screening tool for anal squamous intraepithelial lesions

Anal squamous intraepithelial lesions (ASIL) are common in homosexual and bisexual men, and high-grade ASIL (HSIL) in particular may represent an anal cancer precursor. Cervical cytology is a useful screening tool for detection of cervical HSIL to prevent cervical cancer. To assess anal cytology as a screening tool for anal disease, we compared anal cytology with anoscopy and histopathology of anal biopsies. A total of 2958 anal examinations were performed on 407 HIV-positive and 251 HIV-negative homosexual or bisexual men participating in a prospective study of ASIL. The examination consisted of a swab for anal cytology and anoscopy with 3% acetic acid and biopsy of visible lesions. Defining abnormal cytology as including atypical squamous cells of undetermined significance and ASIL, the sensitivity of anal cytology for detection of biopsy-proven ASIL was 69% (95% confidence interval: 60 to 78) in HIV-positive and 47% (95% confidence interval; 26 to 68) in HIV-negative men at their first visit and was 81% and 50%, respectively, for all subsequent visits combined. The absence of columnar cells did not affect the sensitivity, specificity, or predictive value of anal cytology. Anal cytology may be a useful screening tool to detect ASIL, particularly in HIV-positive men. The grade of disease on anal cytology did not always correspond to the histologic grade, and anal cytology should be used in conjunction with histopathologic confirmation.

The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology.

Abstract The terminology for human papillomavirus (HPV)–associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) Project was cosponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology and included 5 working groups; 3 work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors, and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted on at the consensus meeting. The final, approved recommendations standardize biologically relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail the appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

High Prevalence of Anal Human Papillomavirus Infection and Anal Cancer Precursors among HIV-Infected Persons in the Absence of Anal Intercourse

Context Anal cancer is associated with human papillomavirus (HPV) infection and receptive anal intercourse and is more common in HIV-positive than HIV-negative homosexual men. Little is known about HPV infection and anal lesions in HIV-positive men with no history of receptive anal intercourse. Contribution In this cross-sectional study of HIV-positive men, 46% of 50 heterosexual men who reported no history of receptive anal intercourse had anal HPV infection and 36% had anal squamous intraepithelial lesions. Low CD4+ cell counts were associated with an increased risk for anal lesions. Implications Anal HPV infection and precancerous lesions occur without receptive anal intercourse in HIV-positive men. The Editors The incidence of anal cancer among men with a history of receptive anal intercourse before the HIV epidemic was several times higher than the current rate of cervical cancer in women in the United States; the incidence of anal cancer is estimated to be as high as 35 per 100 000 in this population (1, 2). Anal cancer is associated with human papillomavirus (HPV) infection (3, 4). Earlier studies of the risk for anal cancer in HIV-negative populations showed that a history of receptive anal intercourse was an important risk factor (2, 5), presumably because it increased the risk for acquiring anal HPV infection. Both anal squamous intraepithelial lesions (SILs) and anal HPV infection are more common in HIV-positive than in HIV-negative men who have sex with men (6-13). Recent studies estimated that the incidence of anal cancer was twofold higher in HIV-infected than in HIV-negative men who had sex with men (14, 15); in addition, the relative risk for developing anal cancer among HIV-positive men was 37-fold higher than in the general population (16). Human immunodeficiency virus-positive men who had sex with men were at 60-fold higher risk. Human immunodeficiency virus-positive injection drug users were also at increased risk (6-fold), although less so than the HIV-positive men who had sex with men. In HIV-positive men who have sex with men, it is difficult to ascertain the role of anal intercourse as a risk factor for anal HPV infection or anal SIL, given the high prevalence of this behavior in this population. Immunosuppression probably plays a role, as indicated in studies showing an association between anal SIL and low CD4+ cell counts (6, 10, 13). In addition, evidence shows that the risk for anal SIL is increased in renal allograft recipients in the absence of receptive anal intercourse (17-19). Cervical cytologic screening to detect cervical high-grade SIL (HSIL) followed by treatment of the lesions substantially reduces the incidence of cervical cancer. Studies of anal cytologic screening to determine whether the incidence of anal cancer can similarly be reduced have not yet been done. However, according to costbenefit modeling over a wide range of assumptions, anal cytologic screening in HIV-positive men who have sex with men has been projected to be cost-effective for preventing anal cancer (20, 21). In this cross-sectional study, we compared the prevalence of and risk factors for abnormal anal histologic or cytologic findings in HIV-positive men who have sex with men with male HIV-positive injection drug users who reported no history of anal intercourse. This was done to assess the role of HIV-related immunodeficiency in detecting anal HPV infection and anal disease in the absence of anal intercourse. In addition, we sought to determine whether the prevalence of anal HPV infection and anal SIL was high enough in HIV-positive injection drug users to warrant additional studies of potential benefit from anal cytologic screening in this population. Methods Study Design Between June 1999 and October 2000, 120 HIV-seropositive men attending the outpatient clinic of Hpital Europen Georges Pompidou, Paris, France, were recruited in a cross-sectional study of anal HPV infection and anal SIL in HIV-seropositive men. Men were eligible for the study if they had acquired HIV through homosexual or bisexual contact or through injection drug use, were older than 18 years of age, and had absolute CD4+ cell counts less than 500 106 cells/L. Injection drug users who had sex with men were excluded from the study. The patients were recruited from a cohort of 1198 HIV-infected patients who were followed at the Clinical Immunology unit of Hpital Europen Georges Pompidou. All patients were consecutively enrolled into the study. No eligible patient declined participation. The Ethics Review Board of Hpital Piti-Salpetrire, Paris, and the Committee on Human Research of the University of California, San Francisco, approved the protocol and written informed consent documents. Patients provided signed written consent before inclusion in the study. All men were interviewed by using a standardized, comprehensive, self-administered questionnaire that included questions on age, education status, professional activity, tobacco use, route of HIV infection, medical history, history of sexually transmitted diseases, history of HPV-related disease, history of treatment for anal disease, drug use, age at first intercourse, total number of sexual partners, total number of receptive and insertive anal intercourse, and history of commercial sex work with men. The questionnaire was a French translation of a questionnaire used in other published studies conducted at the University of California, San Francisco (10). The questionnaires were self-administered, and the investigators were blinded to the results to better ensure patient privacy and accuracy of the data. Cytologic and Histologic Analyses Patients had a thorough anal examination that included insertion of a Dacron swab (Eurotubo, Rubi, Spain) for anal cytologic and HPV testing. The swab was immediately rinsed in a vial of PreservCyt fixative fluid (Cytyc Corp., Boxborough, Massachusetts). Each vial was used for HPV testing and ThinPrep cytologic screening (Cytyc Corp.). An aliquot was taken from the vial for HPV testing; slides were then prepared from the vial by using the ThinPrep 2000 processor (Cytyc Corp.). When cytologic abnormalities were found, consenting patients underwent anoscopic examination and biopsy with the use of a colposcope (22). Biopsy specimens were fixed in 10% formalin for routine histopathologic examination. Anal cytologic and histologic results were evaluated independently of each other, without knowledge of clinical status and HIV risk group of the patient or HPV results. Anal cytologic results were classified as normal, atypical squamous cell of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL), or HSIL by using the Bethesda system criteria for evaluation of cervical cytologic results. If both cytologic and histologic results were available for analysis, a patients diagnosis was categorized as the more severe result. Detection of Anal HPV DNA Polymerase chain reaction (PCR) for anal HPV DNA detection was performed in a blinded fashion. To determine specimen adequacy, genomic DNA was isolated from the ThinPrep vial and amplified by using MY09/MY11 consensus HPV L1 primers as well as primers to amplify the human -globin gene (9). After 40 amplification cycles, specimens were probed with a biotin-labeled HPV L1 consensus probe mixture. A separate membrane was probed with biotin-labeled probes for the human -globin gene. We performed type-specific probing for the following HPV types individually: 6; 11; 16; 18; 26; 31; 32; 33; 35; 39; 40; 45; 51; 52; 53; 54; 55; 56; 58; 59; 61; 66; 68; 69; 70; 73; Pap 155; Pap 291; AE2; and a mix containing 2, 13, 34, 42, 57, 62, 64, 67, 72, and W13B. We designated samples that were positive with the consensus probes but negative with the individual type-specific probes as having one or more other types. Polymerase chain reaction can be used to discriminate between low-level HPV infection and high-level HPV infection on the basis of intensity of the PCR signal on Southern blot analysis (23), which was recorded on a scale from 0 (negative) to 5. For the purpose of the analysis, a sample that was positive for more than one HPV high-risk types was categorized as the higher PCR signal from the sample. CD4+ Cell Count and Plasma HIV RNA Viral Load We used the CD4+ cell counts and plasma HIV RNA viral loads closest to the period within 2 months of the anal examination. The nadir CD4+ cell count was defined as the lowest count recorded before the study. Absolute numbers of CD4+ T cells were determined by standard flow cytometry. Plasma HIV RNA levels were determined by the branched-chain DNA signal amplification assay (Quantiplex HIV-RNA, Chiron Diagnostics Corp., Emeryville, California). Statistical Analysis We analyzed data by using StatView 5 software (SAS Institute, Inc., Cary, North Carolina). Because most variables had skewed distribution, data are presented as median and ranges. Differences across HIV risk groups were tested with the Fisher exact test (categorical variables) and the nonparametric Mann-Whitney U test (continuous variables). Patients with HPV infection and histologic or cytologic abnormalities were compared with patients with no evidence of HPV infection or anal disease. To identify risk factors for histologic or cytologic abnormalities, the following dichotomous variables were entered into a logistic regression model: age (<35 vs. 35 years), age at first intercourse (<16 vs. 16 years), number of lifetime sexual partners (<40 vs. 40), number of receptive anal intercourse episodes (<10 vs. 10), current smoking, history of anogenital warts, history of sexually transmitted disease (including anogenital herpes, gonorrhea, and syphilis), CD4+ cell count less than 250 106 cells/L, nadir CD4+ cell count less than 100 106 cells/L, plasma HIV RNA viral load greater than 1.7 log copies/mL, previous AIDS-defining event, current antiretroviral treatment, current protease inhibitor tr