The Kirby Institute for Infection and Immunity in Society, University of New South Wales, Sydney, NSW, Australia.
Lancet Oncol. 2012 May;13(5):487-500. doi: 10.1016/S1470-2045(12)70080-3. Epub 2012 Mar 23.
Men who have sex with men (MSM) are at greatly increased risk of human papillomavirus (HPV)-associated anal cancer. Screening for the presumed cancer precursor, high-grade anal intraepithelial neoplasia (AIN), followed by treatment in a manner analogous to cervical screening, has been proposed. We aimed to assess available data for anal HPV disease that can inform pre-cancer screening programmes.
We searched PubMed, OVID Medline, and Embase for all studies published before Nov 1, 2011, that reported prevalence and incidence of anal HPV detection, AIN, and anal cancer in MSM. We calculated summary estimates using random-effects meta-analysis.
53 studies met the inclusion criteria, including 31 estimates of HPV prevalence, 19 estimates of cytological abnormalities, eight estimates of histological abnormalities, and nine estimates of anal cancer incidence. Data for incident HPV and high-grade AIN were scarce. In HIV-positive men, the pooled prevalence of anal HPV-16 was 35·4% (95% CI 32·9-37·9). In the only published estimate, incidence of anal HPV-16 was 13·0% (9·6-17·6), and clearance occurred in 14·6% (10·2-21·2) of men per year. The pooled prevalence of histological high-grade AIN was 29·1% (22·8-35·4) with incidences of 8·5% (6·9-10·4) and 15·4% (11·8-19·8) per year in two estimates. The pooled anal cancer incidence was 45·9 per 100,000 men (31·2-60·3). In HIV-negative men, the pooled prevalence of anal HPV-16 was 12·5% (9·8-15·4). Incidence of HPV-16 was 11·8% (9·2-14·9) and 5·8% (1·9-13·5) of men per year in two estimates. The pooled prevalence of histological high-grade AIN was 21·5% (13·7-29·3), with incidence of 3·3% (2·2-4·7) and 6·0% (4·2-8·1) per year in two estimates. Anal cancer incidence was 5·1 per 100,000 men (0-11·5; based on two estimates). There were no published estimates of high-grade AIN regression.
Anal HPV and anal cancer precursors were very common in MSM. However, on the basis of restricted data, rates of progression to cancer seem to be substantially lower than they are for cervical pre-cancerous lesions. Large, good-quality prospective studies are needed to inform the development of anal cancer screening guidelines for MSM.
Australian Government Department of Health and Ageing.
男男性行为者（MSM）患人乳头瘤病毒（HPV）相关肛门癌的风险大大增加。人们提议对假定的癌前病变——高级别肛门上皮内瘤变（AIN）进行筛查，然后采用类似于宫颈癌筛查的方法进行治疗。我们旨在评估可用于肛门 HPV 疾病的现有数据，为癌前筛查方案提供信息。
我们在 PubMed、OVID Medline 和 Embase 上检索了截至 2011 年 11 月 1 日发表的所有研究报告，这些研究报告报告了 MSM 中肛门 HPV 检测、AIN 和肛门癌的患病率和发病率。我们使用随机效应荟萃分析计算了汇总估计值。
有 53 项研究符合纳入标准，其中包括 31 项关于 HPV 流行率的研究、19 项关于细胞学异常的研究、8 项关于组织学异常的研究和 9 项关于肛门癌发病率的研究。关于 HPV 新发病例和高级别 AIN 的数据很少。在 HIV 阳性男性中，肛门 HPV-16 的总流行率为 35.4%（95%CI 32.9-37.9）。唯一发表的估计显示，肛门 HPV-16 的发病率为 13.0%（9.6-17.6），每年有 14.6%（10.2-21.2）的男性可清除病毒。组织学高级别 AIN 的总流行率为 29.1%（22.8-35.4），两项研究的发病率分别为 8.5%（6.9-10.4）和 15.4%（11.8-19.8）。肛门癌的总发病率为每 100,000 名男性 45.9 例（31.2-60.3）。在 HIV 阴性男性中，肛门 HPV-16 的总流行率为 12.5%（9.8-15.4）。两项研究的 HPV-16 发病率分别为每年 11.8%（9.2-14.9）和 5.8%（1.9-13.5）。两项研究中组织学高级别 AIN 的总流行率为 21.5%（13.7-29.3），发病率分别为 3.3%（2.2-4.7）和 6.0%（4.2-8.1）。肛门癌的发病率为每 100,000 名男性 5.1 例（0-11.5；基于两项研究）。目前尚无关于高级别 AIN 消退的研究报告。
肛门 HPV 和肛门癌前病变在 MSM 中非常常见。然而，基于有限的数据，癌症进展的速度似乎远低于宫颈癌前病变。需要开展高质量的大型前瞻性研究，为 MSM 肛门癌筛查指南的制定提供信息。
澳大利亚政府卫生部和老龄事务部。
