[Bowen disease of the nail apparatus. Report of 5 cases and review of the 20 cases of the literature (author's transl)].

Five cases of Bowen disease of the nail apparatus were studied and the 20 cases published to date reviewed. The lesion was characterized by either periungual redness with scaling and erosions, whitish cuticle, hyperkeratotic or papilomatous process, fissure or crusted ulcer in the lateral nail fold or the nail bed with eventual partial or total destruction of the nail plate and sometimes soreness on the pressure. The key of the diagnosis is the histological picture, identical with that of Bowen diseases of other skin areas. Among the 25 cases, Bowen disease was found mainly in males (20 out of 25 patients) on the left fingers (17 out of 25 finger lesions) with particular involvement of the 1st, 2nd, 3rd finger nail. Hallux was concerned twice. The clinical picture can be protean and mimic verrucae, onychomycosis, paronychia, eczema, pyogenic granuloma, verrucous tuberculosis, subungual exostosis, glomus tumor, dermatitis vegetans, amelanotic malignant melanoma, kerato-acanthoma and of course squamous cell carcinoma. Treatment of choice is complete removal of the tumor by plastic surgery otherwise microscopically controlled excision following chemical fixation (Mohs) or fresh tissue technique.