Screening for anal dysplasia in women with a history of human papillomavirus related lower genital tract pathology

Background Women with a human papillomavirus related history of cervical, vaginal or vulvar high-grade dysplasia or cancer are at increased risk to develop anal dysplasia or anal cancer. Screening for anal cancer precursors (squamous intraepithelial lesions (SIL)) with high resolution anoscopy (HRA) in high-risk populations is subject of debate. In this study we evaluated standardized intra-anal SIL screening using HRA in high-risk female patients. Methods A retrospective observational study was performed to evaluate the prevalence of intra-anal SIL in women with a history of vulvar high-grade SIL (HSIL) and perianal HSIL diagnosed at the Netherlands Cancer Institute, who were referred for intra-anal SIL screening using HRA in the MC Slotervaart between 2015 and 2017. Results 22 female patients were screened for anal SIL using HRA. 19 females had a history of biopsy proven vulvar HSIL and 19 females had a history of biopsy proven perianal HSIL. Eleven (50%) patients had a history of multizonal HSIL at three or more perianogenital locations. No anal cancer was found at screening, 7 (32%) patients were diagnosed with anal HSIL and 7 (32%) patients with low-grade anal SIL. Conclusions We found a high prevalence of anal HSIL in women with HPV related lower genital tract dysplasia. Intra-anal SIL screening using HRA in this high risk population seems to be justified. However, HRA is an invasive screening method. Studying other, less invasive screening methods remains important.