DCEG investigators are studying risk of anal cancer in HIV-positive men who have sex with men. They have established a screening cohort study of 1,000 HIV-positive men through the Kaiser Permanente Northern California (KPNC) health maintenance program. Under written, informed consent, participating KPNC members will respond to a self-administered risk factor questionnaire and will undergo two anal specimen collections, using liquid-based cytology (LBC) medium, as well as a digital exam and high resolution anoscopy. Participants will be followed annually for two years to collect follow-up clinical data related to outcomes. Baseline clinician-collected specimens will be tested in a masked fashion for the following clinical biomarkers: 1) carcinogenic HPV DNA in aggregate and individual carcinogenic HPV genotypes; 2) carcinogenic HPV RNA and HPV16/18 RNA; 3) cytogenetic changes (3q, 5p, and 20q amplification); and 4) p16INK4a and Ki-67 immunocytochemical staining. For reference, clinician-collected specimens will be used to make LBC slides and evaluated by an expert cytopathology laboratory. Investigators will estimate the HPV genotype-specific risk and the clinical performance (sensitivity, specificity, positive and negative predictive values, and referral rates) of individual tests and combinations of tests for detection of prevalently-detected, one-year cumulative, and two-year cumulative histologically-confirmed anal precancer (anal intraepithelial neoplasia grade 3) or worse (=AIN3). All participants will undergo diagnostic procedures at all visits and independent of testing results, which will result in unbiased disease ascertainment.
For more information, contact Nicolas Wentzensen.