Initiation of an anal cancer screening in HIV+MSM: results of cytology, biopsy and determination of risk factors.

Incidence of anal cancer is increasing and risk of anal cancer is higher in MSM, especially if they are HIV+. European guidelines for treatment of HIV-infected adults recommend anal cancer screening by digital rectal exam±Pap test with anuscopy if Pap test is abnormal. A systematic anal cancer screening in HIV+MSM with anal cytology (Pap smears) was established in June 2011 in our reference centre in Brussels. If anal cytology was abnormal, high-resolution anuscopy (HRA) with biopsy was performed. 353 MSM HIV+were screened by anal smears between June 2011 and May 2012. 90% were Caucasians, median age was 44.5 years, 83% were on HAART and 74% had an undetectable viral load, median CD4 was 632/µl and 33% had a nadir CD4<200. Thirty-three (9.3%) were excluded because of poor quality. Cytology was abnormal in 46% of the 320 remaining patients: high-grade squamous intraepithelial lesion (HSIL) 3%, low-grade squamous intraepithelial lesion (LSIL) 24%, atypical squamous cells of undetermined significance (ASC-US) 16%, and atypical squamous cells / cannot rule out a high-grade lesion (ASC-H) 3%. Viral load (VL) was more frequently undetectable (82% vs 64%, p=0.0003) and median duration of HAART was longer (111 vs 61 months, p=0.0145) in patients with normal cytology. 80 HRA with biopsies have been performed. 12.5% were normal, 44% showed anal intraepithelial neoplasia (AIN) 1, 24% AIN 2 and 19% AIN 3. For this analysis, high-grade AIN (2 and 3) were put together (AIN 2+). Among patients with AIN 2+(n=33), cytology had showed 8 (24%) ASC-US, 3 (9%) ASC-H, 19 (57%) LSIL, 3 (9%) HSIL. When patients with normal cytology or normal biopsy and patients with AIN 2+were compared, the only significant risk factor found for AIN 2+was a nadir CD4<100/µl (32% of the patients with AIN 2+vs 14% in patients with normal smear, p=0.0073). Anal precancerous lesions are frequent and at different stages. Among 46% abnormal cytology, 87% had abnormal biopsy including half AIN 2+.Cytology±biopsy is the only way to detect those lesions and should be performed systematically in HIV+MSM. Risk factor for AIN2+was a nadir CD4<100/µl. A normal cytology was associated with an undetectable VL and a longer duration of HAART. Those results provide further argument for early initiation of HAART. [ABSTRACT FROM AUTHOR]