Papillomavirus-Induced Tumors of the Skin: Cutaneous Warts and Epidermodysplasia Verruciformis

Abstract

Well known since ancient times, cutaneous warts represent epidermal proliferations of varied clinical appearance. At the beginning of the first century AD, Celsus (25) described three types of warts: acrochordons, usually occurring in children and often disappearing spontaneously; thymion, a vascular papillomatous lesion; and myrmecia, resembling our plantar warts. In the following centuries little attention seems to have been paid to their aetiology. John Payne (1891) was the first to record their infectious nature. Later on, in 1907, their inoculability was demonstrated through Ciuffo’s experiments, which suggested the viral nature of a transmissible agent. The virus material itself was isolated in microcrystalline form by Strauss et al. in 1949. In the subsequent 2 decades it was assumed that a single virus — the human wart virus — was responsible for all infectious warty lesions of the skin. It was identified as a double-stranded DNA virus, belonging to the Papovaviridiae family (Pfister 1984). Nowadays, the plurality of human papillomaviruses (HPV) is well-established. More than 40 different types can be isolated and characterised by modem techniques of molecular biology.