Cutaneous human papillomaviruses as recurrence factor in actinic keratoses

Actinic keratoses (AK) are common, premalignant lesions cause mainly by UV DNA damage. Progression into squamous cell carcinoma may be influenced by other several factors such as chronic chemical exposure or viral infection. A carcinogenic role of Human Papillomaviruses (HPV) in early steps of skin tumour development was recently hypothesized; moreover the presence of HPV DNA seems to be higher in cancer precursor lesions. The aim of this work is to identify the presence of HPV DNA in biopsies from Actinic Keratoses (AK) and from normal skin samples collected from dermatological healthy subjects in Italy, in order to evaluate the severity and the clinical evolution of the HPV positive lesions. The DNA test revealed 37% HPV positivity in AK patients versus 0% in the control group; many different genotypes and variants were identified by direct sequencing of PCR product. The HPV positive AK were usually clinically indistinguishable from the HPV negative. All AK lesions were removed by laser treatment, but AK lesions recurred in all HPV positive patients after a period of 45-60 days whereas the same disappeared in the HPV negative ones. These data permit to hypothesize that the presence of HPV DNA could be an aggravating factor for AK lesion severity and recurrence.