Strategies for screening and early detection of anal cancers: A narrative and systematic review and meta-analysis of cytology HPV testing and other biomarkers

摘要

Anal cancer incidence and mortality have been increasing over the past decade. While the incidence in the general population remains low, it is much higher in certain subgroups including those living with human immunodeficiency virus (HIV), and men who have sex with men (MSM). Approximately 90% of anal squamous cell cancers are caused by infection with carcinogenic human papillomavirus (HPV). Given the common etiology between anal and cervical carcinogenesis, screening for anal cancer has been proposed in certain high-risk populations using strategies adapted from cervical cancer prevention. In this review, we discuss important differences in anal and cervical cancer regarding the populations at risk, disease natural history, and clinical procedures and outcomes that need to be considered when evaluating strategies for anal cancer screening. We also performed a systematic review and meta-analysis of the performance of anal cytology, anal HPV testing, and various biomarkers for detection of anal precancers and cancers. We summarize the implications of these performance estimates in the context of risk-based screening and management of anal precancers and we highlight important research gaps that need to be addressed to fully understand the benefits and harms of anal cancer screening.