Routine Screening of Anal Cytology in Persons With Human Immunodeficiency Virus and the Impact on Invasive Anal...

The efficacy of screening programs to prevent anal cancer in persons with human immunodeficiency virus 1 (HIV-1) is unclear.

To examine the impact of a screening program to detect anal cancer precursors on the incidence of cases of invasive anal squamous-cell carcinoma (IASCC) in persons with HIV-1, we performed a single-center, retrospective analysis of a prospective cohort of outpatients with HIV-1 attending a reference HIV unit from January 2005 onward. All participants were invited to participate in a continued structured screening program for anal cancer prevention. We estimated the incidence of IASCC and performed a comparative analysis between subjects enrolled in the screening program (screening group) and those who declined to participate (nonscreening group). To reduce any selection bias, a propensity score analysis was applied.

We included 3111 persons with HIV-1 (1596 men-who-have-sex-with-men [MSM], 888 men-who-have-sex-with-women [MSW], 627 women; mean age, 41 years), with a median follow-up of 4.7 years (14 595 patient-years of follow-up); 1691 (54%) participated in the screening program. Ten patients were diagnosed with IASCC: 2 (MSM) in the screening group and 8 (4 MSM, 2 MSW, and 2 women) in the nonscreening group. The incidence rates of IASCC were 21.9 (95% confidence interval [CI], 2.7-70.3) and 107.0 (95% CI, 46.2-202.0) per 100 000 person-years, respectively. After a propensity score adjustment, the difference was significant in favor of the screening group (hazard ratio, 0.17; 95% CI, .03-.86).

The number of cases of IASCC was significantly lower in persons with HIV engaged in an anal cytology screening program. These results should be validated in a randomized clinical trial.