Anal squamous cell carcinoma is the most common type of anal cancer and is largely associated with anal human papillomavirus infection. The incidence of anal squamous cell carcinoma is increasing, and although still uncommon in the general population, a high incidence has been noted in specific population groups (eg, patients with HIV, men who have sex with men [MSM], recipients of solid organ transplants, women with genital neoplasia, and patients with systemic lupus erythematosus or inflammatory bowel disease). The higher incidence among individuals who are HIV-positive makes anal squamous cell carcinoma one of the most common non-AIDS-defining cancers among HIV-positive individuals. Anal cancer screening in high-risk groups aims to detect high-grade squamous intraepithelial lesions, which are considered anal precancerous lesions, and for which identification can provide an opportunity for prevention. A blind anal cytology is normally the first screening method, and for patients with abnormal results, this approach can be followed by an examination of the anal canal and perianal area under magnification, along with staining—a technique known as high-resolution anoscopy. Digital anorectal examination can enable early anal cancer detection. Several societies are in favour of screening for HIV-positive MSM and recipients of transplants. There are no current recommendations for screening of anal precancerous lesions via endoscopy, but in high-risk groups, a careful observation of the squamocolumnar junction should be attempted. Several treatments can be used to treat high-grade squamous intraepithelial lesions, including argon plasma coagulation or radiofrequency ablation, which are largely limited by high recurrence rates. Gastroenterologists need to be aware of anal squamous cell carcinoma and anal precancerous lesions, given that patients at high risk are frequently encountered in the gastroenterology department. We summarise simple procedures that can help in early anal squamous cell carcinoma detection.

肛门鳞状细胞癌是最常见的肛门癌类型，主要与肛门人乳头瘤病毒感染有关。肛门鳞状细胞癌的发病率正在增加，虽然在一般人群中仍然不常见，但在特定人群中的发病率很高（例如，HIV 患者、男男性行为者 [MSM]、实体器官移植受者）。移植、生殖器瘤形成的女性以及系统性红斑狼疮或炎症性肠病患者）。HIV 阳性个体中较高的发病率使得肛门鳞状细胞癌成为 HIV 阳性个体中最常见的非艾滋病定义癌症之一。高危人群的肛门癌筛查旨在检测高级别鳞状上皮内病变，这些病变被认为是肛门癌前病变，识别可以提供预防的机会。盲法肛门细胞学通常是第一种筛查方法，对于结果异常的患者，此方法之后可以在放大镜下检查肛管和肛周区域，并进行染色——一种称为高分辨率肛门镜检查的技术。肛门直肠指检可以及早发现肛门癌。一些社会赞成筛查 HIV 阳性 MSM 和移植受者。目前没有通过内窥镜筛查肛门癌前病变的建议，但在高危人群中，应尝试仔细观察鳞柱交界处。几种治疗方法可用于治疗高级别鳞状上皮内病变，包括氩等离子体凝固或射频消融，这在很大程度上受到高复发率的限制。鉴于胃肠科经常遇到高危患者，胃肠病学家需要了解肛门鳞状细胞癌和肛门癌前病变。我们总结了有助于早期肛门鳞状细胞癌检测的简单程序。