[Effectiveness of human papillomavirus genotyping for detection of high-grade anal intraepithelial neoplasia compared to anal cytology]

Anal intraepithelial neoplasia screening in women from the largest center for lower genital tract disease in China

This study aimed to provide comprehensive clinical screening data for anal intraepithelial neoplasia (AIN). This study included 312 patients who underwent high-resolution anoscopy (HRA) examinations between January 1, 2020 and April 15, 2024. Clinical data, including demographic information, clinical history, cytology/high-risk human papilloma virus (hrHPV) results, and HRA records, were analyzed. The median age of all patients was 42 years (interquartile range: 33-52 years). Approximately 26.3% reported a history of VIN2/3+, 13.5% had a history of VaIN2/3+, 29.8% had a history of CIN2/3+, 44.6% had persistent cervical HPV16 infection, and 12.5% had immune suppression. Among the 312 patients, 14.4% were diagnosed with AIN2/3, 25.0% with AIN1 and 60.6% were normal. Anal cytological abnormalities were found in 41.3% of all patients, with a significantly higher rate in AIN2/3 patients than in ≤AIN1, 71.1% versus 36.3%, p < 0.001. The hrHPV positivity rate was 89.7%, with HPV16 being the most prevalent. The complete agreement rate for HRA impressions was 79.5%. Multi-variable analysis revealed immune suppression (odds ratio [OR]: 3.47, 95% confidence interval [CI]: 1.42-8.5) and VIN2/3+ (OR: 2.82, 95% CI: 1.27-6.28) were independent risk factors for AIN2/3. Abnormal cytology results (OR: 3.3, 95% CI: 1.52-7.17) and anal HPV16 infection (OR: 3.2, 95% CI: 1.26-8.12) demonstrated similar ORs for AIN2/3. Early screening for AIN2/3+ is crucial in Chinese women with lower genital tract precancerous and cancerous lesions, particularly in those with VIN2/3+ and immune suppression.

Our experience in the short-term diagnostic-therapeutic management of the patient with anal dysplasia

INTRODUCTION

Anal intraepithelial neoplasia (AIN) is a premalignant lesion of anal squamous cell carcinoma. HIV-positive males who have sex with males, are the most affected at-risk population. Cytology and anuscopy are the best accepted methods for its diagnosis, although it is controversial which patients should complete it with a biopsy. Neither which patients should undergo treatment nor which is the best treatment is not well established. With this study, we would like to present our experience in the diagnostic-therapeutic management of AIN in the short term.

METHODS

Retrospective observational study of patients at risk of AIN with altered anal cytology who underwent high-resolution anuscopy with biopsy. After histological confirmation of dysplasia, they started treatment with trichloroacetic acid. Its effectiveness was verified by subsequent cytology. The demographic variables of the sample and the results of both diagnostic and treatment tests were analyzed.

RESULTS

The majority were HIV-positive males (104/115) and 50% had sexual relations with other men. We included 115 patients with altered anal cytology, of whom 92% had dysplasia on biopsy. 97% with atypia of uncertain significance on cytology had histological dysplasia. Cytology normalized after treatment in 60% of patients.

CONCLUSION

Early detection of AIN should be routinely considered in known at-risk populations. Any cytological abnormality should be biopsied. Tricholoroacetic acid can be an effective treatment achieving a high percentage of regression, although currently, the information we have is of low level of evidence.

Anal intraepithelial neoplasia: A review of diagnosis and management

Anal intraepithelial neoplasia (AIN) is a premalignant lesion of the anal mucosa that is a precursor to anal cancer. Although anal cancer is relatively uncommon, rates of this malignancy are steadily rising in the United States, and among certain high risk populations the incidence of anal cancer may exceed that of colon cancer. Risk factors for AIN and anal cancer consist of clinical factors and behaviors that are associated with the acquisition and persistence of human papilloma virus (HPV) infection. The strongest HPV-associated risk factors are HIV infection, receptive anal intercourse, and high risk sexual behavior. A history of HPV-mediated genital cancer, which suggests infection with an oncogenic HPV strain, is another risk factor for AIN/anal cancer. Because progression of AIN to anal cancer is known to occur in some individuals over several years, screening for AIN and early anal cancer, as well as treatment of advanced AIN lesions, is reasonable in certain high-risk populations. Although randomized controlled trials evaluating screening and treatment outcomes are lacking, experts support routine screening for AIN in high risk populations. Screening is performed using anal cytological exams, similar to those performed in cervical cancer screening programs, along with direct tissue evaluation and biopsy via high resolution anoscopy. AIN can be treated using topical therapies such as imiquimod, 5-flurouracil, and trichloroacetic acid, as well as ablative therapies such as electrocautery and laser therapy. Reductions in AIN and anal cancer rates have been shown in studies where high-risk populations were vaccinated against the oncogenic strains of HPV. Currently, the CDC recommends both high-risk and average-risk populations be vaccinated against HPV infection using the quadrivalent or nonavalent vaccines. It is important for clinicians to be familiar with AIN and the role of HPV vaccination, particularly in high risk populations.