Pre-diagnostic dynamic HPV16 IgG seropositivity and risk of oropharyngeal cancer

Objective: The aim of this study was to determine the association of HPV16 antibodies (Abs) and oropharyngeal cancer (OPC) risk in sera obtained prior to clinical diagnosis.

Methods: We identified 92 participants with incident OPC and 460 matched controls from the Janus Serum Bank Cohort in Norway. Archived tumor specimens were requested for a subset of the cases. Serum samples were collected from cases, on average, 9.3years before diagnosis (range, 0.1-14.9years). Ten cases had serum samples from multiple time points. IgG seropositivity to 8 HPV16 antigens was determined, and a logistic regression classifier of a panel of all early-antigen (EA) Abs for the predictive diagnosis of OPC was applied.

Results: HPV16 EA seropositivity was present in 25.0% of patients with OPC and 7.6% of controls (odds ratio (OR), 4.1; 95% CI, 2.3-7.2, p<0.0001). Abs to E2 were strongly associated with cases 0-2years pre- diagnosis (OR, 150.1; 95% CI, 27.4-1040.0, p<0.0001), and the probability of seropositivity was inversely associated with time to diagnosis (OR, 0.7 per additional year; 95% CI, 0.6-0.9, p=0.0002). Abs to E2 were also strongly associated with tumor HPV status (OR, 35.6; 95% CI, 8.7-200.0, p<0.0001). A positive score on the binary classifier was associated with an overall OR of 15.8 (95% CI, 5.6-53.4) compared with controls (p<0.05), and was strongly associated with tumor HPV status (OR, 27.4; 95% CI, 8.6-99.6, p<0.001).

Conclusions: HPV16 Abs are detectable years prior to diagnosis of OPC, and the probability of seropositivity increases closer to diagnosis.