Anal cancer screening: Techniques and guidelines

Prevalence of HPV in anal cancer: exploring the role of infection and inflammation

Anal cancer incidence is rising globally, driven primarily by human papillomavirus (HPV) infection. HPV, especially high-risk types 16 and 18, is considered a necessary cause of anal squamous cell carcinoma. Certain populations like people living with HIV, men who have sex with men, inflammatory bowel disease patients, smokers, and those with compromised immunity face elevated risk. Chronic inflammation facilitates viral persistence, cell transformation, and immune evasion through pathways involving the PD-1/PD-L1 axis. HIV coinfection further increases risk by impairing immune surveillance and epithelial integrity while promoting HPV oncogene expression. Understanding these inflammatory processes, including roles of CD8 + T cells and PD-1/PD-L1, could guide development of immunotherapies against anal cancer. This review summarizes current knowledge on inflammation's role in anal cancer pathogenesis and the interplay between HPV, HIV, and host immune factors.

To Improve Motivational Barriers to Retention in High Resolution Anoscopy, Patients and Providers Recommend Social and Environmental Changes: A Sequential Explanatory Mixed-Methods Pilot Study in a Federally Qualified Health Center

Loss to follow-up (LTFU) in high-resolution anoscopy (HRA) programs jeopardizes the procedure's potential to help prevent anal cancer. We explored quality improvement factors to understand how to address this LTFU. Using the transtheoretical COM-B Model (Capability, Opportunity, Motivation, and Behavior) and a sequential explanatory mixed-methods design, we surveyed and interviewed 13 patients who remained engaged in HIV care but who delayed their HRA monitoring or treatment visits in the same community clinic, and 6 HRA clinicians and medical assistants. Analyses involved descriptive statistics and rapid qualitative analysis. Patients were racially, ethnically, and economically representative of the LTFU population, and were generally experienced with HRA (Mean HRA visits = 4.6, SD = 2.8, mdn = 3). Providers were experienced clinicians and medical assistants (Mean years providing HRA = 6.0, SD = 2.2). Analyses revealed two primary, related barriers: (A) motivational barriers such as physical pain, discomfort, embarrassment, and anxiety; which were largely borne from (B) opportunity barriers such as difficulties with scheduling, inconsistent after-care (particularly for pain and discomfort), anxiety-inducing exam rooms and equipment, and internalized and anticipated stigma. Capability barriers, such as limited health literacy about HRA, were less common and, like motivational barriers, linked to opportunity barriers. Participants recommended potential facilitators, including easier scheduling, standardization of pain management and after-care services, and examination room modifications to reduce anxiety. To retain HRA patients in community settings, interventions should address social and physical opportunity barriers that strongly determine motivational and capability barriers. Improving convenience, standardizing pain management, and introducing stigma interventions specific to HRA, could alleviate both motivational and capability barriers.

Demographic Influences on Adult HPV Vaccination: Results from a Cross-Sectional Survey in Tennessee

HPV is the most prevalent sexually transmitted infection in the U.S., with more than 80% of all Americans contracting it by age 45. Effective vaccines for HPV exist and were recently approved for adults aged 27-45 years, though uptake remains low in all age groups, particularly in Tennessee where 1089 cancers were attributed to HPV in 2020. Between 29 June and 17 August 2023, we conducted a cross-sectional survey to gain insights about the barriers and facilitators of HPV in 2011 adults aged 18 to 45 years in Tennessee. We developed our survey based on previous instruments to understand predictors of HPV vaccination in adults. Using descriptive statistics and bivariate and logistic regression analyses, we found higher vaccination rates in females, participants aged 18-38 years, participants with a high school education or higher, Hispanic or Latine individuals, and participants identifying as moderate or liberal. These insights highlight the need for public health interventions that consider demographic differences to successfully increase vaccination rates and reduce HPV-associated cancer risk.

Human Papillomavirus Genotypes Infecting the Anal Canal and Cervix in HIV+ Men and Women, Anal Cytology, and Risk Factors for Anal Infection

The incidence of anal intraepithelial neoplasias associated with HPV is rising worldwide. In the general population, this pathology is rare, but individuals living with HIV/AIDS are at a significantly higher risk. We aimed to study HPV infection and performed cytological screening to study the epidemiological and behavioral determinants in a group of men and women living with HIV from a region in Mexico with high HIV incidence. This was a cross-sectional study including adults living with HIV/AIDS performed in Merida (Mexico). We invited patients of public HIV/STD clinics and those affiliated with social organizations of people living with HIV to participate in the study. Participants responded to an instrument to assess their risky behaviors and clinical history. Swabs from the anal canal and cervix and anal cytology specimens were obtained by medical staff from women and by self-sampling from men. For the 200 participants, 169 men and 31 women, anal HPV PCR tests resulted in 59.8% positivity (62.6% of men and 45.2% of women), and 17 genotypes were identified. The most frequent high-risk (HR) types for the anal canal were: HPV33 (35.3%), HPV58 (20.6%), HPV66 (18.6%), HPV45 (17.6%), and HPV16 (14.7%). Multiple genotypes were found in over 80% of the participants. Receptive anal intercourse in the previous 12 months, inconsistent condom use, and detectable HIV titers (≥50 cc/mL) were associated with HPV infection (p < 0.05). Cytology (smears and liquid-based) identified that 34.6% of the participants had low-grade squamous intraepithelial lesions (LSILs), and 3.5% had high-grade squamous intraepithelial lesions (HSILs). Neither HPV nor lesions were associated with low CD4+ counts (<200 cells/mm³, p > 0.05). Of the women, 60% were infected in the cervix and 45% in the anal canal, with an agreement of at least one genotype in 90%. The HR-HPV types associated with HSILs were HPV66, 33, 52, 51, 45, 18, and 68.

Human Papillomavirus Genotypes Predict Progression of Anal Low-Grade Squamous Intraepithelial Lesions

Background

High-risk human papillomavirus (hrHPV)-induced anal low-grade squamous intraepithelial lesions (LSILs) have the potential to progress to high-grade squamous intraepithelial lesions (HSILs). We investigated whether anal hrHPV infections, particularly types 16 and 18, predict LSIL-to-HSIL progression.

Methods

One hundred forty-six human immunodeficiency virus (HIV)-infected and 22 HIV-uninfected patients with anal LSILs underwent cytology, HPV genotyping (16, 18, and pooled 12 hrHPV types), and high-resolution anoscopy-guided biopsy at baseline and surveillance. The associations between the rate of LSIL-to-HSIL progression and HPV types as well as longitudinal HPV-16/18 status were assessed by fitting separate Cox regression models.

Results

At baseline, 91% of patients harbored hrHPV: HPV-16/18 (44%) and non-16/18 (86%). Upon follow-up (median, 20 [range, 6-36] months), 41% developed HSIL (84% at the same anatomic location as the initial LSIL and 16% at a different location). Baseline HPV-16/18-positive patients had greater probability of progression than patients with non-16/18 types or negative (67%, 25%, and 7%, respectively; P < .001). Persistent HPV-16/18 conferred the highest probability of progression (70%), followed by intermittent HPV-16/18 positivity (52%). In unadjusted and adjusted analyses, baseline and persistent HPV-16/18 were significantly associated with LSIL-to-HSIL progression.

Conclusions

Anal LSIL patients who are positive for hrHPV, especially HPV-16/18, have an increased risk of developing HSIL. Type-specific HPV testing could serve as a risk stratification tool, providing prognostic information.

Practice parameters for the diagnosis and treatment of anal intraepithelial neoplasia (AIN) on behalf of the Italian Society of Colorectal Surgery (SICCR)

Squamous cell carcinoma (SCC) of the anus is a human papilloma virus (HPV) related malignancy that is preceded by anal intraepithelial neoplasia (AIN) making this cancer, at least theoretically, a preventable disease. In the past 10 years the diagnosis, management and nomenclature of AIN has dramatically changed. Increased life expectancy in human immunodeficiency virus (HIV) positive patients due to highly active antiretroviral therapy (HAART) has caused an increase in the incidence of SCC of the anus. While many experts recommend screening and treatment of anal high-grade squamous intraepithelial lesion (HSIL), there is no consensus on the optimal management these lesions. Therefore, there is a need to review the current evidence on diagnosis and treatment of AIN and formulate recommendations to guide management. Surgeons who are members of the Italian Society of Colorectal Surgery (SICCR) with a recognized interest in AIN were invited to contribute on various topics after a comprehensive literature search. Levels of evidence were classified using the Oxford Centre for Evidence-based Medicine of 2009 and the strength of recommendation was graded according to the United States (US) preventive services task force. These recommendations are among the few entirely dedicated only to the precursors of SCC of the anus and provide an evidence-based summary of the current knowledge about the management of AIN that will serve as a reference for clinicians involved in the treatment of patients at risk for anal cancer.

The acceptability of high resolution anoscopy examination in patients attending a tertiary referral centre

BACKGROUND

High resolution anoscopy (HRA) examination is regarded as the best method for the management of anal high grade squamous intraepithelial lesions to prevent anal squamous carcinoma. However, little is known about the acceptability of this procedure. This analysis looks at patient experience of HRA examination and ablative treatment under local anaesthetic.

METHODS

Patients took part in anonymised feedback of their experience immediately after their HRA examinations and/or treatments. A standard questionnaire was used that included assessment of pain and overall satisfaction scores as well as willingness to undergo future HRA examinations.

RESULTS

Four hundred four (89.4%) responses were received and all responses were analysed. The group consisted of 119 females (29.4%) and 261 males (64.6%) with median age of 45 years (IQR = 19) and 45 years (IQR = 21) respectively, and included 58 new cases, 53 treatment cases and 202 surveillance cases. 158 patients (39.1%) had at least one biopsy during their visits. The median pain score was 2 [Inter Quartile Range (IQR) 3] on a visual analogue scale of 0 to 10, where 0 indicated no pain / discomfort and 10 indicated severe pain. The median pain score was 2 (IQR 2) in men and 4 (IQR = 3) in women [Dunn's Test = 4.3, p < 0.0001] and 3 (IQR 4.5) in treatment cases. Problematic pain defined as a pain score of ≥7 occurred more frequently in women (14%) than in men (6%), [Chi square test (chi2) = 5.6, p = 0.02]. Patient satisfaction with the care they received, measured on a scale of 0 (not happy) to 10 (very happy) found the median score to be 10 with 76% reporting a score of 10. Out of 360 responses, 98% of women and 99% of men said that they would be willing to have a future HRA examination.

CONCLUSIONS

In this cohort, the overall pain scores were low and similar across appointment types. However, women had a higher pain score, including troublesome pain levels. Despite this, both women and men were equally satisfied with their care and were willing to have a future examination. The results of the analysis show that the procedure is acceptable to patient groups. A small number of women may need general anaesthesia for their examinations/treatment.