A broad spectrum of human papillomavirus types is present in the skin of Australian patients with non-melanoma skin cancers and solar keratosis

Background Human papillomavirus (HPV) may play a role in the pathogenesis of non-melanoma skin cancer (NMSC) in epidermodysplasia verruciformis (EV) patients, but in the general population no specific HPV types have been associated with these lesions. Objectives To examine the spectrum of HPV types present in the skin and tumours of Australian patients with NMSC or solar keratosis (SK). Methods Biopsies from tumours, and cotton swab samples of perilesional skin and buttock skin from each of 59 Australian patients with basal cell carcinoma (BCC), squamous cell carcinoma (SCC) or SK were tested for HPV DNA by polymerase chain reaction (PCR) using HPV consensus (FAP) primers and by type-specific primers for HPV 38 and candidate HPV 92. The identification of HPV type from consensus PCR was performed by sequencing and comparison with GenBank. Results In total, 49 of 59 (83%) patients harboured HPV DNA, which was detected in 28 of 64 (44%) biopsies, 48 of 64 (75%; P < 0.001) perilesional swabs and 36 of 59 (61%; P = 0.04) buttock swabs. Forty-five different HPV types/putative types were detected: 15 were previously characterized HPV types, 17 were earlier described putative types and 13 were new putative types. In addition, six subtypes and four variants of HPV sequences were identified. HPV types within the B1 group (EV HPV types) were found in 26 of 64 (40%) lesions, 44 of 64 (69%) perilesional swabs and 35 of 59 (59%) buttock swabs. HPV 38 was detected in 23 of 59 (39%) patients, and was found in seven of 16 (43%) SKs, but was less common in SCCs [three of 23 (13%); P = 0.037] and BCCs [four of 25 (16%); P = 0.056]. Candidate HPV 92 was found in seven of 59 (12%) patients. Conclusions A broad spectrum of HPV types, the majority from the B1 group, was found in skin of Australian patients with skin tumours. HPV 38 was found significantly more often in SK than in SCC. However, the role of cutaneous HPV infection in the pathogenesis of NMSC remains elusive.