International Anal Neoplasia Society's consensus guidelines for anal cancer screening

The International Anal Neoplasia Society (IANS) developed consensus guidelines to inform anal cancer screening use among various high-risk groups. Anal cancer incidence estimates by age among risk groups provided the basis to identify risk thresholds to recommend screening. Guided by risk thresholds, screening initiation at age 35 years was recommended for men who have sex with men (MSM) and transgender women (TW) with HIV. For other people with HIV and MSM and TW not with HIV, screening initiation at age 45 years was recommended. For solid organ transplant recipients, screening initiation beginning from 10 years post-transplant was recommended. For persons with a history of vulvar precancer or cancer, screening initiation was recommended starting within 1 year of diagnosis of vulvar precancer or cancer. Persons aged ≥45 years with a history of cervical/vaginal HSIL or cancer, perianal warts, persistent (>1 year) cervical HPV16, or autoimmune conditions could be considered for screening with shared decision-making, provided there is adequate capacity to perform diagnostic procedures (high-resolution anoscopy [HRA]). Anal cytology, high-risk (hr) human papillomavirus (HPV) testing (including genotyping for HPV16), and hrHPV-cytology co-testing are different strategies currently used for anal cancer screening that show acceptable performance. Thresholds for referral for HRA or follow-up screening tests are delineated. These recommendations from IANS provide the basis to inform management of abnormal screening results, considering currently available screening tools. These guidelines provide a pivotal foundation to help generate consensus among providers and inform the introduction and implementation of risk-targeted screening for anal cancer prevention.

Two-Year Incidence and Cumulative Risk and Predictors of Anal High-Grade Squamous Intraepithelial Lesions (Anal Precancer) Among Women With Human Immunodeficiency Virus

BACKGROUND

Detection and treatment of anal histologic high-grade squamous intraepithelial lesions (hHSIL) prevents anal cancer. However, anal hHSIL incidence among women with human immunodeficiency virus (HIV, WHIV) remains unknown. Performance of anal high-risk human papillomavirus ([hr]HPV), anal cytology (anal-cyt), and both for hHSIL detection longitudinally over 2 years also remains undetermined.

METHODS

We determined 2-year incidence and cumulative risk estimates (2-y-CR) of anal hHSIL among WHIV using prevalence and incidence (per 100 person-years [py]) observations stratified by baseline hrHPV and/or anal-cyt results.

RESULTS

In total, 229 WHIV with complete baseline data were included in the analysis; 114 women without prevalent anal hHSIL were followed with 2 annual evaluations. Median age was 51, 63% were Black, and 23% were Hispanic. Anal hrHPV or abnormal anal-cyt was associated with an increased risk of incident anal hHSIL at 2 years (18.9/100py [95% confidence interval {CI} 11.4-31.3] and 13.4/100py [95% CI 8.0-22.7], respectively) compared with no detection of anal HPV or negative cytology (2.8/100py [95% CI 1.1-7.4] and 4.2 [95% CI, 1.8-10.2]) The presence of anal hrHPV with abnormal cytology was associated with 2-y-CR of anal hHSIL of 65.6% (95% CI 55.4%-75%); negative hrHPV with negative cytology was associated with 2-y-CR of anal hHSIL of 9.2% (95% CI 7.0-16.0).

CONCLUSIONS

Detection of anal hrHPV or abnormal anal cytology are comparable predictors for 2-y-CR of anal hHSIL. The absence of anal hrHPV combined with negative cytology was predictive of a lower (but measurable) risk of developing anal hHSIL. These findings provide important data to inform anal cancer screening guidelines for WHIV.

Understanding Sexual and Gender Minority Populations and Organ-Based Screening Recommendations for Human Papillomavirus-Related Cancers

OBJECTIVES

Sexual gender minority (SGM) populations are at risk for human papillomavirus (HPV)-related cancers of the anogenital tract and oropharynx and often face barriers to health care. The goals of this document are to clarify language to provide inclusive care for SGM populations and to provide recommendations for screening and prevention of HPV-related cancers in SGM populations.

MATERIALS AND METHODS

An expert committee convened by the American Society for Colposcopy and Cervical Pathology performed a narrative review of the literature through February 2023. A comprehensive MEDLINE database search was performed for relevant studies. The literature review was divided into categories by organ/topic and by SGM population. Given the variability in available data for several of the categories, recommendations were made based on national guidelines where appropriate or expert opinion where there were less data to support risk-based guidelines.

RESULTS

Definitions and terminology relevant to SGM populations are presented. The authors advocate the adoption of sexual orientation gender identity data collection and an organ-based screening approach, which is possible with knowledge of patient anatomy, sexual behaviors, and clinical history. This includes screening for cervical cancer per national recommendations, as well as screening for anal, vulvar, vaginal, penile, and oral cancers based on risk factors and shared clinical decision making. The authors recommend consideration of HPV vaccination in all SGM individuals up to age 45 years old who are at risk.

CONCLUSIONS

An organ-based screening approach is part of a global strategy to create an inclusive care environment and mitigate barriers to screening and prevention of HPV-mediated cancers in SGM populations.

Brazilian Society of Surgical Oncology: Guidelines for the management of anal canal cancer

BACKGROUND

Anal canal squamous cell carcinoma (SCC) is a relatively uncommon neoplasia, and it is mostly a local-regional cancer, of low metastatic potential (only 15%), resulting in cure in most cases treated with definitive chemoradiation. On the other hand, its incidence has been steadily increasing over the last decades, which makes it an important public health problem. In an effort to provide surgeons and oncologists who treat patients with anal cancer with the most updated information based on the best scientific evidence, the Brazilian Society of Surgical Oncology (SBCO) has produced the present guideline for the management of anal canal SCC, focused on the main topics related to daily clinical practice.

OBJECTIVES

The SBCO developed the present guidelines to provide recommendations on the main topics related to the management of anal canal squamous cell carcinoma (SCC) based on current scientific evidence.

METHODS

Between October 2022 and January 2023, 14 experts met to develop the guidelines for the management of anal canal cancer. A total of 30 relevant topics were distributed among the participants. The methodological quality of a final list with 121 sources was evaluated, all the evidence was examined and revised, and the management guidelines were formulated by the 14-expert committee. To reach a final consensus, all the topics were reviewed in a meeting that was attended by all the experts.

RESULTS

The proposed guidelines contained 30 topics considered to be highly relevant in the management of anal canal cancer, covering subjects related to screening recommendations, preventive measures, tests required for diagnosing and staging, treatment strategies, response assessment after chemoradiotherapy, surgical technique-related aspects, and follow-up recommendations. In addition, screening and response assessment algorithms, and a checklist were proposed to summarize the important information and offer an updated tool to assist surgeons and oncologists who treat anal canal cancer and in providing the best care to their patients.

CONCLUSION

These guidelines summarize recommendations based on the most current scientific evidence on relevant aspects of anal canal cancer management and are a practical guide to help surgeons and oncologists who treat anal canal cancer make the best therapeutic decisions.

State Variation in Squamous Cell Carcinoma of the Anus Incidence and Mortality, and Association With HIV/AIDS and Smoking in the United States

PURPOSE

Squamous cell carcinoma of the anus (SCCA) incidence and mortality rates are rising in the United States. Understanding state-level incidence and mortality patterns and associations with smoking and AIDS prevalence (key risk factors) could help unravel disparities and provide etiologic clues.

METHODS

Using the US Cancer Statistics and the National Center for Health Statistics data sets, we estimated state-level SCCA incidence and mortality rates. Rate ratios (RRs) were calculated to compare incidence and mortality in 2014-2018 versus 2001-2005. The correlations between SCCA incidence with current smoking (from the Behavioral Risk Factor Surveillance System) and AIDS (from the HIV Surveillance system) prevalence were evaluated using Spearman's rank correlation coefficient.

RESULTS

Nationally, SCCA incidence and mortality rates (per 100,000) increased among men (incidence, 2.29-3.36, mortality, 0.46-0.74) and women (incidence, 3.88-6.30, mortality, 0.65-1.02) age ≥ 50 years, but decreased among men age < 50 years and were stable among similar-aged women. In state-level analysis, a marked increase in incidence (≥ 1.5-fold for men and ≥ two-fold for women) and mortality (≥ two-fold) for persons age ≥ 50 years was largely concentrated in the Midwestern and Southeastern states. State-level SCCA incidence rates in recent years (2014-2018) among men were correlated (r = 0.47, P < .001) with state-level AIDS prevalence patterns. For women, a correlation was observed between state-level SCCA incidence rates and smoking prevalence (r = 0.49, P < .001).

CONCLUSION

During 2001-2005 to 2014-2018, SCCA incidence and mortality nearly doubled among men and women age ≥ 50 years living in Midwest and Southeast. State variation in AIDS and smoking patterns may explain variation in SCCA incidence. Improved and targeted prevention is needed to combat the rise in SCCA incidence and mitigate magnifying geographic disparities.

A systematic review and meta-analysis of cytology and HPV-related biomarkers for anal cancer screening among different risk groups

To inform optimal approaches for detecting anal precancers, we performed a systematic review and meta-analysis of the diagnostic accuracy of anal cancer screening tests in different populations with elevated risk for anal cancer. We conducted a literature search of studies evaluating tests for anal precancer and cancer (anal intraepithelial neoplasia grade 2 or worse, AIN2+) published between January 1, 1997 to September 30, 2021 in PubMed and Embase. Titles and abstracts were screened for inclusion and included articles underwent full-text review, data abstraction and quality assessment. We estimated the prevalence of AIN2+ and calculated summary estimates and 95% confidence intervals (CI) of test positivity, sensitivity and specificity and predictive values of various testing strategies, overall and among population subgroups. A total of 39 articles were included. The prevalence of AIN2+ was 20% (95% CI, 17-29%), and ranged from 22% in men who have sex with men (MSM) living with HIV to 13% in women and 12% in MSM without HIV. The sensitivity and specificity of cytology and HPV testing were 81% and 62% and 92% and 42%, respectively, and 93% and 33%, respectively for cytology and HPV co-testing. AIN2+ risks were similar among those testing positive for cytology, HPV, or co-testing. Limited data on other biomarkers (HPV E6/E7 mRNA and p16/Ki-67 dual stain), suggested higher specificity, but lower sensitivity compared with anal cytology and HPV. Our findings provide important evidence for the development of clinical guidelines using anal cytology and HPV testing for anal cancer screening.

Treatment of Anal High-Grade Squamous Intraepithelial Lesions to Prevent Anal Cancer

BACKGROUND

The incidence of anal cancer is substantially higher among persons living with the human immunodeficiency virus (HIV) than in the general population. Similar to cervical cancer, anal cancer is preceded by high-grade squamous intraepithelial lesions (HSILs). Treatment for cervical HSIL reduces progression to cervical cancer; however, data from prospective studies of treatment for anal HSIL to prevent anal cancer are lacking.

METHODS

We conducted a phase 3 trial at 25 U.S. sites. Persons living with HIV who were 35 years of age or older and who had biopsy-proven anal HSIL were randomly assigned, in a 1:1 ratio, to receive either HSIL treatment or active monitoring without treatment. Treatment included office-based ablative procedures, ablation or excision under anesthesia, or the administration of topical fluorouracil or imiquimod. The primary outcome was progression to anal cancer in a time-to-event analysis. Participants in the treatment group were treated until HSIL was completely resolved. All the participants underwent high-resolution anoscopy at least every 6 months; biopsy was also performed for suspected ongoing HSIL in the treatment group, annually in the active-monitoring group, or any time there was concern for cancer.

RESULTS

Of 4459 participants who underwent randomization, 4446 (99.7%) were included in the analysis of the time to progression to cancer. With a median follow-up of 25.8 months, 9 cases were diagnosed in the treatment group (173 per 100,000 person-years; 95% confidence interval [CI], 90 to 332) and 21 cases in the active-monitoring group (402 per 100,000 person-years; 95% CI, 262 to 616). The rate of progression to anal cancer was lower in the treatment group than in the active-monitoring group by 57% (95% CI, 6 to 80; P = 0.03 by log-rank test).

CONCLUSIONS

Among participants with biopsy-proven anal HSIL, the risk of anal cancer was significantly lower with treatment for anal HSIL than with active monitoring. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT02135419.).

Provider Preferences for Anal Cancer Prevention Screening: Results of the International Anal Neoplasia Society Survey

Objective

This study explores provider preferences regarding anal cancer screening indications, initiation age, tools, and referral threshold to high resolution anoscopy (HRA).

Methods

International Anal Neoplasia Society affiliates were invited to complete an online survey. Options for initiation age and tools were delineated by sub-groups. HRA referral thresholds separately queried recommendations by patient immune status.

Results

One hundred forty respondents participated. Although consensus was lacking with regard to specific screening initiation age, more respondents recommended younger initiation ages for men who have sex with men (MSM) living with HIV (LWH) compared with MSM not LWH (p < 0.01). “No age threshold” ranged 44-55% among sub-groups with lower genital tract disease. Cytology and digital anorectal exam (DARE) were the most frequently selected tools for all sub-groups (ranges 77-90% and 74-86%, respectively). HRA was recommended significantly more frequently for MSM LWH (58%) and patients with vulvar cancer (52%) compared to others (p < 0.01). “Any [test] abnormality” was more often selected as indication for HRA for immunocompromised (56%) and immunocompetent (46%) patients than a specific cytology test result (29%, 36% respectively).

Conclusion

Cytology and DARE were preferred screening tools; screening initiation age and HRA referral threshold showed less consensus. Evidence-based guidelines are needed and may lead to more consistent screening practices.

Design of the ANal Cancer/HSIL Outcomes Research study (ANCHOR study): A randomized study to prevent anal cancer among persons living with HIV

It is well established that persons living with HIV (PLWH) have highly elevated rates of anal HSIL and anal cancer compared with those who are not living with HIV. The 5-year risk of anal cancer following anal HSIL has been reported to be as high as 14.1% among PLWH compared with 3.2% among those who are not living with HIV. To address these concerns, the AIDS Malignancy Consortium completed a large-scale, randomized trial to compare strategies for the prevention of anal cancer among PLWH with anal HSIL. The objective of the study was to determine whether treating anal HSIL was effective in reducing the incidence of anal cancer in PLWH compared with active monitoring. This paper describes the design of the ANal Cancer/HSIL Outcomes Research Study (ANCHOR) with respect to estimating the anal cancer event rate in this high risk population.

Gaps and Opportunities to Improve Prevention of Human Papillomavirus-Related Cancers

Human papillomavirus (HPV) infections cause more than 35,900 cancers annually in the United States. Although cervical cancer is the most prevalent HPV-related malignancy in women, the virus is also responsible for a significant percentage of anal, vaginal, and vulvar cancers. A comprehensive approach to mitigating cervical cancer includes HPV vaccination (primary prevention), screening and treatment of precancerous lesions (secondary prevention), and diagnosis and treatment of invasive cancer (tertiary prevention). Although a successful strategy, there are opportunities to innovate and increase access that can also be adapted to address the unique clinical care gaps that exist with the other anogenital cancers. The Society for Women's Health Research held a series of interdisciplinary meetings and events, during which expert researchers, clinicians, patient advocates, and health care policy leaders evaluated the current landscape of HPV-related cancers and their effects on women's health. This report summarizes the discussions of this working group and areas it identified in which to address gaps in primary and secondary prevention approaches to improve access and health outcomes for women with HPV-related anogenital cancers.

Xpert HPV as a Screening Tool for Anal Histologic High-Grade Squamous Intraepithelial Lesions in Women Living With HIV

BACKGROUND

Women living with HIV (WLWH) experience high rates of anal cancer. Screening using anal cytology, high-resolution anoscopy (HRA) with biopsies, can histologically diagnose anal cancer precursors called high-grade squamous intraepithelial lesions (HSIL). The low specificity of screening using anal cytology results in HRA referral for many WLWH without HSIL. Screening using high-risk human papillomavirus (HR-HPV) may improve specificity.

METHODS

Two hundred seven WLWH (63% non-Hispanic black) were screened for anal histologic HSIL (hHSIL) using cytology, HRA-guided biopsies, and Xpert HPV. Xpert performance for predicting anal hHSIL was compared with that of cytology. Usng Xpert 5 HPV genotypic results and accompanying cycle thresholds, receiver operator characteristic curve and recursive partitioning analyses were used to create predictive models for hHSIL.

RESULTS

The performance of Xpert to predict hHSIL was not different from that of cytology with a sensitivity (Sn) of 89% and specificity (Sp) of 49%. Interpretation of Xpert was modified using genotypic results and receiver operator characteristic curve analysis, which produced a screen with an Sn and Sp of 75% and 84% for hHSIL, respectively. Another reinterpretation of Xpert was created using recursive partitioning and cycle thresholds, which predicted hHSIL with an Sn and Sp of 75% and 86%, respectively. The detection of HPV-16 was highly predictive of hHSIL in all analyses. These modified screening tests would reduce HRA referral in this population by almost half compared with anal cytology.

CONCLUSIONS

Xpert HPV is an alternative to anal cytology to screen for anal HSIL and can be optimized to reduce the number of unnecessary HRAs performed in WLWH.

Prevalence of and Risk Factors for Anal High-grade Squamous Intraepithelial Lesions in Women Living with Human Immunodeficiency Virus

BACKGROUND

Women living with human immunodeficiency virus (WLHIV) have disproportionately high rates of squamous cell carcinoma of the anus compared with the general population of women. Anal high-grade squamous intraepithelial lesions (HSILs) precede anal cancer, and accurate studies of HSIL prevalence among WLHIV in the United States are lacking.

METHODS

The AIDS Malignancy Consortium 084 study was a multicenter national trial to evaluate the prevalence of and risk factors for anal HSIL in a US cohort. Eligible participants were WLHIV aged ≥18 years with no history of anal HSIL. Study participants had an examination including collection of cervical/vaginal and anal specimens, followed by high-resolution anoscopy with biopsy.

RESULTS

We enrolled 256 women with evaluable anal pathology. The mean age was 49.4 years, 64% women were non-Hispanic black, 67% were former or current smokers, and 56% reported ever having anal sex with a man. The median CD4 T-cell count was 664 cells/μL. The prevalence of anal histologic HSIL (hHSIL) was 27% (95% confidence interval [CI], 22%-33%). There was a strong concordance (240/254) between local and consensus pathologists for hHSIL vs less than hHSIL (κ = 0.86 [95% CI, .79-.93]). Current CD4 count of ≤200 cells/μL was the strongest predictor of consensus anal hHSIL diagnosis (adjusted odds ratio [aOR], 10.34 [95% CI, 3.47-30.87]). History of anoreceptive intercourse was also associated with hHSIL (aOR, 2.44 [95% CI, 1.22-4.76]).

CONCLUSIONS

The prevalence of anal hHSIL in WLHIV in the United States was 27% in this study where all participants received high-resolution anoscopy and biopsy.

A Randomized Clinical Trial of Infrared Coagulation Ablation Versus Active Monitoring of Intra-anal High-grade Dysplasia in Adults With Human Immunodeficiency Virus Infection: An AIDS Malignancy Consortium Trial

BACKGROUND

Anal high-grade squamous intraepithelial lesions (HSILs) ablation may reduce the incidence of invasive cancer, but few data exist on treatment efficacy and natural regression without treatment.

METHODS

An open-label, randomized, multisite clinical trial of human immunodeficiency virus (HIV)-infected adults aged ≥27 years with 1-3 biopsy-proven anal HSILs (index HSILs) without prior history of HSIL treatment with infrared coagulation (IRC). Participants were randomized 1:1 to HSIL ablation with IRC (treatment) or no treatment (active monitoring [AM]). Participants were followed every 3 months with high-resolution anoscopy. Treatment participants underwent anal biopsies of suspected new or recurrent HSILs. The AM participants underwent biopsies only at month 12. The primary end point was complete clearance of index HSIL at month 12.

RESULTS

We randomized 120 participants. Complete index HSIL clearance occurred more frequently in the treatment group than in the AM (62% vs 30%; risk difference, 32%; 95% confidence interval [CI], 13%-48%; P < .001). Complete or partial clearance (clearance of ≥1 index HSIL) occurred more commonly in the treatment group (82% vs 47%; risk difference, 35%; 95% CI, 16%-50%; P < .001). Having a single index lesion, compared with having 2-3 lesions, was significantly associated with complete clearance (relative risk, 1.96; 95% CI, 1.22-3.10). The most common adverse events related to treatment were mild or moderate anal pain and bleeding. No serious adverse events were deemed related to treatment or study participation.

CONCLUSION

IRC ablation of anal HSILs results in more clearance of HSILs than observation alone.

Targets for adapting intravenous iron dose in hemodialysis: a proof of concept study

BACKGROUND

Intravenous iron is widely used to control anemia in dialysis patients and limits costs related to erythropoiesis-stimulating agents (ESA). Current guidelines do not clearly set upper limits for serum ferritin (SF) and transferrin saturation (TSAT). International surveys such as the Dialysis Outcomes and Practice Patterns Study (DOPPS) showed that this lack of upper limits potentially led nephrologists to prescribe iron infusions even for patients with a high SF. Recent publications have suggested a risk of short- and long-term adverse effects related to iron overload. We conducted a proof of concept study to assess the impact of reducing intravenous iron administration.

METHODS

In a prospective 8-month study conducted in a hospital dialysis unit, we assessed the impact of a strategy designed to reduce iron infusions. Instead of the usual strategy targeting 30-50% TSAT irrespective of SF, intravenous iron was administered if and only if TSAT was below 20% and SF below 200 μg/L. Routine practices for ESA remained unchanged: hemoglobin target 10-12 g/dL; ESA delivered monthly and dose corrected by 25% as necessary; ESA discontinued temporarily if hemoglobin >13 g/dL; methoxy polyethylene glycol-epoetin beta generally used. Tests were ordered monthly to monitor hemoglobin. Intravenous iron was administered weekly and ESA monthly. Baseline and 6-month TSAT, SF and hemoglobin levels were compared.

RESULTS

Six-month data were available for 45 patients (31 M/14 F; 67.6 ± 14.0 y; 53.9 ± 85.7 months on dialysis). Patients experienced the following comorbidities: ischemic heart disease (n = 29, 44%), diabetes mellitus (n = 14; 31%), malignant disease (n = 11; 24%), transplantation (n = 11; 24%) and severe heart failure (n = 6; 13%). The mean weekly dose of iron declined from 77.8 ± 87.6 to 24.4 ± 52.9 mg per patient (p = 0.0003). SF decreased from 947.7 ± 1056.4 to 570.7 ± 424.4 μg/L (p = 0.0001), and TSAT from 41.5 ± 22.4 to 32.6 ± 13.7% (p = 0.01). Hemoglobin levels remained stable (11.13 ± 1.05 vs. 11.00 ± 1.16 g/dL, p = 0.54) as did ESA dose (126.4 ± 91.9 vs. 108.2 ± 112.7 μg/28 days, p = 0.07).

CONCLUSIONS

Our study suggests that a regular hemoglobin level can be maintained using regular ESA doses combined with intravenous iron doses adapted to TSAT and SF thresholds lower than those used in routine practice. This strategy reduces the risk of iron overload.

Colposcopic Characteristics and Lugol's Staining Differentiate Anal High-Grade and Low-Grade Squamous Intraepithelial Lesions During High Resolution Anoscopy

Background

Methods

Results

Conclusions

Screening for Anal Cancer in Women

OBJECTIVE

The incidence of anal cancer is higher in women than men in the general population and has been increasing for several decades. Similar to cervical cancer, most anal cancers are associated with human papillomavirus (HPV), and it is believed that anal cancers are preceded by anal high-grade squamous intraepithelial lesions (HSIL). Our goals were to summarize the literature on anal cancer, HSIL, and HPV infection in women and to provide screening recommendations in women.

METHODS

A group of experts convened by the American Society for Colposcopy and Cervical Pathology and the International Anal Neoplasia Society reviewed the literature on anal HPV infection, anal SIL, and anal cancer in women.

RESULTS

Anal HPV infection is common in women but is relatively transient in most. The risk of anal HSIL and cancer varies considerably by risk group, with human immunodeficiency virus-infected women and those with a history of lower genital tract neoplasia at highest risk compared with the general population.

CONCLUSIONS

While there are no data yet to demonstrate that identification and treatment of anal HSIL leads to reduced risk of anal cancer, women in groups at the highest risk should be queried for anal cancer symptoms and required to have digital anorectal examinations to detect anal cancers. Human immunodeficiency virus-infected women and women with lower genital tract neoplasia may be considered for screening with anal cytology with triage to treatment if HSIL is diagnosed. Healthy women with no known risk factors or anal cancer symptoms do not need to be routinely screened for anal cancer or anal HSIL.

Incidence of and risk factors for type-specific anal human papillomavirus infection among HIV-positive MSM

OBJECTIVE

HIV-positive MSM are at increased risk of anal human papillomavirus (HPV) infection compared with men in the general population, and little is known about the natural history of anal HPV infection in this population. The objective of this study was to determine the incidence of and risk factors for anal type-specific HPV infection.

DESIGN

Prospective cohort study.

METHODS

HIV-positive MSM were evaluated for anal HPV DNA, lifestyle factors, and sexual risk behaviors every 6 months for at least 2 years.

RESULTS

The overall incidence rate of detectable type-specific anal HPV infection was 21.3 per 100 person-years [95% confidence interval (CI) 17.7-25.4] and was 13.3/100 person-years (10.5-16.6) for oncogenic HPV types. The most common incident infections were HPV 18 (3.7/100 person-years) and HPV 16 (3.5/100 person-years). An increased number of recent partners with whom the participant was the receptive partner [odds ratio (OR) 2.9 (1.6-5.1) 8+ partners vs. 0-1], an increased number of new partners in which the participant was the receptive partner [OR 1.03 (1.01-1.1) per partner], an increased number of new oral-anal contact partners in which the participant was the receptive partner [OR 1.1 (1.03-1.1) per partner], and the frequency of receptive anal intercourse [OR 1.1 (1.03-1.1) per act] all significantly increased the odds of incident HPV infection (P ≤ 0.05).

CONCLUSION

HIV-positive MSM have a high incidence of oncogenic anal HPV infection. Recent receptive anal sexual behaviors, including receptive anal intercourse and receptive oral-anal contact, are the most important risk factors for incident anal HPV infection.

Progression of anal high-grade squamous intraepithelial lesions to invasive anal cancer among HIV-infected men who have sex with men

The incidence of anal cancer is elevated in human immunodeficiency virus (HIV)-infected men-who-have-sex-with-men (MSM) compared to the general population. Anal high-grade squamous intraepithelial lesions (HSIL) are common in HIV-infected MSM and the presumed precursors to anal squamous cell cancer; however, direct progression of HSIL to anal cancer has not been previously demonstrated. The medical records were reviewed of 138 HIV-infected MSM followed up at the University of California, San Francisco, who developed anal canal or perianal squamous cancer between 1997 and 2011. Men were followed up regularly with digital anorectal examination (DARE), high-resolution anoscopy (HRA) and HRA-guided biopsy. Although treatment for HSIL and follow-up were recommended, not all were treated and some were lost to follow-up. Prevalent cancer was found in 66 men. Seventy-two HIV-infected MSM developed anal cancer while under observation. In 27 men, anal cancer developed at a previously biopsied site of HSIL. An additional 45 men were not analyzed in this analysis due to inadequate documentation of HSIL in relation to cancer location. Of the 27 men with documented progression to cancer at the site of biopsy-proven HSIL, 20 men progressed from prevalent HSIL identified when first examined and seven men from incident HSIL. Prevalent HSIL progressed to cancer over an average of 57 months compared to 64 months for incident HSIL. Most men were asymptomatic, and cancers were detected by DARE. Anal HSIL has clear potential to progress to anal cancer in HIV-infected MSM. Early diagnosis is facilitated by careful follow-up. Carefully controlled studies evaluating efficacy of screening for and treatment of HSIL to prevent anal cancer are needed.

Risk factors for anal human papillomavirus infection type 16 among HIV-positive men who have sex with men in San Francisco

BACKGROUND

HIV-positive men who have sex with men (MSM) are at high risk of anal cancer compared with the general population. Human papillomavirus (HPV) infection, particularly HPV 16, is causally associated with anal cancer. However, the risk factors for anal HPV 16 infection are poorly understood. We determined the prevalence and risk factors for anal HPV 16 infection in a population of HIV-positive MSM, most of whom were being treated with antiretroviral therapy.

DESIGN

Cross-sectional data from the baseline visit of a 4-year prospective cohort study.

METHODS

Three hundred forty-eight HIV-positive MSM were recruited in San Francisco, and they received a detailed sexual behavior risk factor questionnaire. An anal swab was used to collect specimens for HPV type-specific DNA testing using L1 HPV DNA polymerase chain reaction. We used log-binomial multivariable models to determine the risk factors for anal HPV 16 infection.

RESULTS

Ninety-two percent of HIV-positive MSM had at least 1 anal HPV type, 80% had at least 1 oncogenic HPV type, and 42% had HPV 16. Non-Hispanic white race and higher level of education were associated with a decreased risk of HPV 16 infection. A higher number of total male partners was associated with HPV 16 (relative risk: 1.6, 95% confidence interval 1.1 to 2.4, P = 0.01) for 201-1000 partners compared with 1-200. Injection drug use was independently associated with anal HPV 16 infection (relative risk: 1.5, 95% confidence interval 1.2 to 1.9, P = 0.003).

CONCLUSIONS

The prevalence of anal HPV infection, including HPV 16, is high in HIV-positive MSM. HIV-positive MSM should be counseled about the risk associated with increased partners and injection drug use.

High-grade anal intraepithelial neoplasia among HIV-1-infected men screening for a multicenter clinical trial of a human papillomavirus vaccine

PURPOSE

High-grade anal intraepithelial neoplasia (HGAIN) is the precursor lesion to invasive anal cancer. Human papillomavirus (HPV) vaccination holds great promise for preventing anal cancer.

METHODS

We examined 235 HIV-1-infected men screening for participation in a multisite clinical trial of a quadrivalent HPV vaccine. All participants had anal swabs obtained for HPV testing and cytology and high-resolution anoscopy with biopsies of visible lesions to assess for HGAIN.

RESULTS

HPV types 16 and 18 were detected in 23% and 10%, respectively; abnormal anal cytology was found in 56% and HGAIN in 30%. HGAIN prevalence was significantly higher in those with HPV16 detection compared to those without (38% vs 17%; P = .01). Use of antiretroviral therapy and nadir and current CD4+ cell count were not associated with abnormal anal cytology or HGAIN.

CONCLUSION

HGAIN is highly prevalent in HIV-infected men. Further studies are needed on treatment and prevention of HGAIN.

32. HPV type and strain variant concordance between anal cancers and their preceding high-grade squamous intraepithelial lesions

Background Anal high-grade squamous intraepithelial lesions (HSIL) are frequently found overlying anal cancer on histology, and anal cancer has been observed to develop in the same location as previously diagnosed anal HSIL. These observations support the role of HSIL as the direct precursor lesion to anal cancer. To further investigate a direct pathogenetic relationship between anal HSIL and cancer, we typed and sequenced HPV DNA in anal HSIL and the cancers that subsequently developed in the same location. Methods: Tissues samples were analysed from 15 HIV-infected men followed at UCSF in whom anal cancer developed at a previously biopsied site of HSIL. Formalin-fixed paraffin-embedded pairs of HSIL and cancer were typed for HPV DNA using L1 PCR. HPV 16-positive samples underwent E6-based strain variant analysis. Results: Nine matched pairs for which DNA from both HSIL and cancer were available were analysed. Eight pairs (89%) contained HPV 16 DNA. One (11%) contained both HPV 18 and 51 in both samples. Of the eight HPV 16-positive pairs, each pair contained the same HPV 16 strain variant. Four contained the Eur-350T variant alone, and one contained Eur-350T in both the HSIL and cancer, with an additional 426T variant in the cancer. One pair contained both Eur-350T and 457C in both the HSIL and the cancer. Two pairs contained the Eur-350G variant alone. Conclusions: Concordance of both the HPV type and strain variant in anal cancers and their site-matched preceding HSIL further supports the role of anal HSIL as an anal cancer precursor.

18. Topical 5% 5-flourouracil (t5FU) for treatment of diffuse anal high-grade squamous intraepithelial lesions (aHSIL)

Background Treatment of anal high-grade squamous intraepithelial lesions (aHSIL) may prevent anal cancer. Options for treatment of diffuse lesions include staged ablation, often requiring surgery, although in-office treatment is preferable. Topical 5% 5-fluorouracil (t5FU) has been used to treat diffuse female genital HPV-associated disease. We report our experience using t5FU for treatment of diffuse aHSIL considered unsuitable for ablation, to evaluate its tolerability and efficacy. Methods: Patients were given t5FU for treatment of diffuse aHSIL in doses of 0.5 mL self-applied 2× daily for 5 days followed by 9 days off. Patients were assessed on average following 4–8 cycles for complete response (CR), defined as the absence of HSIL on exam, cytology and/or histology, or partial response (PR), defined as a reduction in the amount of disease. Patients with PR then received ablative therapy. Results: 73 patients (55 HIV infected, 18 uninfected) were treated, including 13 women and 60 men. In 69 patients who used t5FU for at least one cycle, CR occurred in 8 (~11%) patients, 53 (~77%) had a partial response indicating reduction of disease, 6 (9%) had no response, and 1 had more widespread disease, 1 chart was not evaluable. Treatment was discontinued after <1 cycle in 4 patients due to side effects. Patients with PR were treated successfully with in-office ablation, except 2 patients referred for surgery. Conclusions: t5FU was well tolerated although side effects occur. Most patients had clinical improvement, suggesting that t5FU may play an important role in aHSIL treatment. Further studies may determine its optimal use.

3. Outcome of excision of early invasive squamous carcinomas of the anal canal and perianus

Background Combined modality therapy (CMT) is the standard of care for anal canal (AC) squamous cell carcinoma (SCCA); excision is reserved for small perianal (PA) cancers. Increasingly, asymptomatic, superficially invasive SCCAs (SISCCA) are identified during high-resolution anoscopy (HRA). For AC- and PA-SISCCA, the Lower Anogenital Squamous Terminology Project’s proposed definition is an excised tumour with clear margins, depth of invasion <3 mm, and horizontal extent <7 mm. We report our experience with surgical excision alone of early invasive SCCA (EISCCA), defined as AC- or PA-SISCCA and >SISCCA, but with clear margins. Methods: EISCCA were excised sparing the anal sphincter and anal high-grade squamous intraepithelial lesions (HSIL) were ablated. Those with margins positive for SCCA were referred for CMT. HRA was performed every 4 months; recurrent HSIL/EISCCA was ablated or excised. Patients were referred for CMT if cancer could not be excised without compromising the sphincter. Results: EISCCA was excised in 81 patients: 68 men and 13 women, 57 HIV-infected and 24 HIV-uninfected. Median age was 52 years (range: 33–79). Patients were followed for a median of 43 months (range: 2–230) following excision. Excision of EISCCA was successful in 73 (90%) patients. Eight (10%) required CMT (4 developed inguinal node recurrences, including 2 with systemic metastases). There was no statistically significant difference in outcome by location (AC v. PA EISCCA), HIV status or sex (P > 0.05). Conclusions: Excision of EISCCA, including AC tumours, produces an excellent outcome, sparing most patients CMT, including those with HIV infection.