[Lichen ruber hypertrophicus with verrucous carcinoma].

A 51-year-old patient presented with aggregated papules and with a central, partly erosive plaque on the left lower leg. Histological examination revealed hypertrophic lichen planus peripherally and a verrucous carcinoma within the centre. The lesion was removed surgically. Shortly after wards an atrophic lichen planus developed exclusively within the skin graft, which was effectively treated with topical steroid cream. The patient remained disease-free for 2 years. The literature relating to malignant transformation of cutaneous lichen planus was reviewed. In most cases, as in the present one, the hypertrophic form of lichen planus and the verrucous type of carcinoma (Ackerman) are reported. Recent investigations have revealed human papilloma virus types 6 and 11 within such lesions.