Human papillomavirus and post-transplant cutaneous squamous-cell carcinoma: a multicenter, prospective cohort study

Organ-transplant recipients (OTR) have a 100-fold increased risk of cutaneous squamous-cell carcinoma (cSCC). We prospectively evaluated the association between beta-genus human-papillomaviruses (betaPV) and keratinocyte carcinoma in OTR. Two OTR cohorts without cSCC were assembled: cohort 1 transplanted in 2003-2006 (n=274) and cohort 2 in 1986-2002 (n=352). Participants were followed until death or cessation of follow-up in 2016. BetaPV infection was assessed in eyebrow hairs using PCR-based methods. BetaPV IgG seroresponses were determined by multiplex serology. A competing risk model with delayed entry was used to estimate cumulative incidence of histologically proven cSCC and the effect of betaPV using a multivariable Cox regression model. Results are reported as adjusted hazard ratios (HR). OTR with ≥5 different betaPV types in eyebrow hairs had 1.7 times the risk of cSCC versus those with 0-4 different types (HR: 1.7 (1.1;2.6)). A similar risk was seen with high betaPV loads (HR: 1.8 (1.2;2.8)). No significant associations were seen between serum antibodies and cSCC or between betaPV and basal-cell carcinoma. The diversity and load of betaPV types in eyebrow hairs are associated with cSCC risk in OTR, providing evidence that betaPV is associated with cSCC carcinogenesis and may present a target for future preventive strategies. This article is protected by copyright. All rights reserved.