Antibodies against HPV16E6 oncoprotein in the Swiss HIV Cohort Study: kinetics and anal cancer risk prediction

Our aim was to describe HPV16E6 antibody kinetics prior to anal cancer in people living with HIV/AIDS (PLWHA) and evaluate the possible contribution of HPV16E6 serology to anal cancer risk prediction. For 91 persons diagnosed with anal cancer in the Swiss HIV Cohort Study (1989-2017), serial serum/plasma samples were tested for HPV16E6 antibodies using multiplex serology, supplemented with samples from 1,356 participants without anal cancer. Anal cancer incidence was estimated for PLWHA from 40 years-old in the cART era, stratified by HPV16E6 serostatus. HPV16E6 seroprevalence was 23.3% in samples 10 years. Of 25 individuals with anal cancer who were HPV16E6-seropositive at any time during follow-up, the majority (n=18) remained seropositive in all samples following seroconversion, whereas for 7 cases, seropositivity was transitory. Among individuals with anal cancer, HPV16E6 seroprevalence was marginally higher in women versus men who have sex with men (adjusted OR=4.3, 95% CI: 1.1, 17.2) and in older participants (adjusted OR=6.2, 95% CI: 1.1, 34.8 for cases diagnosed at ≥55 versus