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Squamous cell carcinoma (SCC) of the anal canal has been increasing globally and disproportionately impacts certain key populations.1 In 2024, the International Anal Neoplasia Society (IANS) published the first evidence-based guidelines on anal cancer screening.2 These guidelines identify the key populations to screen, when to start yearly screening and which screening tests to use (table 1). Like cervical cancer, nearly all anal SCC are caused by infection with oncogenic types of human papillomavirus (HPV).1 Anal SCC is rare at the population level, with 1–2 cases per 100 000 person-years; however, older age and other factors (eg, immunosuppression) are associated with higher anal SCC rates, with the highest incidence seen in gay, bisexual and other men who have sex with men living with HIV (85 cases per 100 000 person-years).3 Despite the recent release of the IANS guidelines, most regions, including those across the UK, still do not have organised screening programmes.