Prevalence of high-grade anal intraepithelial neoplasia in immunocompetent women treated for high-grade cervical intraepithelial neoplasia

Background: The aim of the study was to evaluate the prevalence of high-grade anal intraepithelial neoplasia (AIN2-3) among immunocompetent women treated for high-grade cervical intraepithelial neoplasia (CIN2-3). Such knowledge is strongly needed to establish whether a screening program should be recommended in this group of patients.

Methods: This prospective study included a cohort of consecutive women with no known causes of immunosuppression treated with LEEP (loop electrosurgical excision procedure) for a histopathological diagnosis of CIN2-3 in our center between 2019 and 2021. Following the procedure, all patients were invited to undergo anal cytology and anal high-risk HPV-DNA testing (aHPV-DNA). In cases in which one or both tests resulted positive, a high-resolution anoscopy with a biopsy of suspicious lesions was performed. All women also completed a questionnaire on sexual habits.

Results: At total of 100 women were enrolled in the study. Among these, eight patients had a concomitant or past diagnosis of anogenital warts, while one patient had received a previous diagnosis of high-grade vaginal intraepithelial neoplasia. Anal Pap smears were positive for low-grade lesions in three patients, while 73 women tested positive for aHPV-DNA. Histological examinations revealed the presence of AIN2-3 lesions in four patients (6.5%; 95% C.I., 1.8 to 15.7%), who subsequently underwent excisional treatment.

Conclusions: Women with a history of high-grade cervical intraepithelial neoplasia have an intermediate risk of developing high-grade anal intraepithelial neoplasia. Future studies are needed in order to assess an ideal screening approach for this condition.