Distribution of high-risk α-genus human papillomavirus genotypes impacts cutaneous neoplasms

High-risk α-genus human papillomaviruses (α-HPVs) are linked to cervical and genital carcinomas; however, their correlation with cutaneous squamous cell carcinoma (cuSCC) or premalignant skin lesions remains controversial.

We evaluated the contribution of high-risk α-HPV to the occurrence of cuSCC, Bowen's disease and actinic keratosis (AK), and the distribution of high-risk α-HPV genotypes in these cutaneous tumours.

HPV genotypes were determined using a commercial PCR-based microarray on skin tissue samples collected from 76 [38 young (<60 years) and 38 elderly (>60 years)] cuSCC, 34 Bowen's disease, 48 AK patients and 10 young controls. Associations between α-HPV prevalence and relevant risk factors were analysed.

High-risk α-HPV was more frequently detected in cuSCC patients (57.9%) than in the patients with Bowen's disease (38.2%), AK (0.0%) and control patients (10.0%). The high-risk α-HPV prevalence was higher in young than in elderly cuSCC patients (65.8% vs. 50.0%, P = 0.031). The most common HPV type was 16, present in 90.9% of all HPV-carrying cuSCC patients. Multiple infections with different high-risk α-HPV types were found in 20.5% of HPV-related cuSCC, whereas only single infection with type 16 was found in Bowen's disease. Although sun exposure is known as a major risk factor for cuSCC, high-risk α-HPVs were more frequently found in non-exposed sites rather than in sun-exposed sites of cuSCC.

Multiple infections, as well as single infection with high-risk α-HPV may link to cuSCC. In spite of the involvement of high-risk α-HPV at high levels in cuSCC and Bowen's disease, no high-risk α-HPV was detected in AK patients, suggesting that Bowen's disease rather than AK might be involved in the development of HPV-related cuSCC as a precursor.