Severe anal intraepithelial neoplasia trends and subsequent invasive anal cancer in the United States

Menée aux Etats-Unis à partir de données 1996-2019 issues de 11 registres des cancers, cette étude analyse, en fonction du sexe et de la présence d'une infection par le VIH, l'évolution de l'incidence d'une néoplasie intraépithéliale anale sévère et le risque de développer un cancer anal invasif

Résumé en anglais

Background: Anal intraepithelial neoplasia grade III (AIN3) is a precursor to squamous cell carcinoma of the anus (SCCA), for which rates are nearly 20-fold higher in people with HIV (PWH) than in the general population in the US. We describe trends in AIN3 diagnosis and risk of SCCA following AIN3 by HIV status and sex.

Methods: We utilized data from a population-based linkage between cancer and HIV registries in 11 US states, Puerto Rico, and Washington DC during 1996–2019. We identified all individuals with a diagnosis of AIN3 and determined their HIV status. We estimated the average annual percentage change (AAPC) of AIN3 using Poisson regression stratified by HIV status and sex. We estimated the 5-year cumulative incidence of SCCA following an AIN3 diagnosis stratified by sex, HIV status, and prior AIDS diagnosis.

Result: Among PWH, AAPCs for AIN3 were 15% (95%CI=12–17%) per year among females 12% (95%CI=11–14%) among males. AAPCs for those without HIV were 8% (95%CI=7–8%) for females and 8% (95%CI=6–9%) for males. Among PWH, a prior AIDS diagnosis was associated with a 2.7-fold (95%CI=2.23–3.40) and 1.9-fold (95%CI=1.72–2.02) increased risk of AIN3 diagnosis for females and males, respectively. 5-year cumulative incidence of SCCA following AIN3 for PWH with a prior AIDS diagnosis were 3.4% and 3.7% for females and males, respectively.

Conclusions: Rates of AIN3 diagnoses have increased since 1996, particularly for PWH, likely influenced by increased screening. A prior AIDS diagnosis was strongly associated with risk of AIN3 diagnosis.