[Retinoids and the prevention of cutaneous epitheliomas: 1977-1987].

In 1977 we undertook a prospective study aimed at evaluating the preventive effects of a retinoid (etretinate, Roche) on the occurrence of skin carcinomas in dermatoses carrying a high risk of malignancy. Ten patients were included in the study: 4 had Xeroderma pigmentosum (XP), 4 had basal cell naevus syndrome (BCN), and there was 1 case each of porokeratosis of Mibelli (PM) and familial epitheliomatosis of Ferguson-Smith (EFS). All recorded carcinomas had been cured before treatment was initiated. The number of epitheliomas which developed during treatment with etretinate was compared with the number of epitheliomas recorded during the months or years preceding this treatment or during trial periods without treatment. The results obtained were very encouraging: 1. In patients with XP the actinic keratosis rapidly regressed, and the dryness of the skin was markedly reduced during the 5 years under etretinate. During the period without etretinate skin dryness and multiple actinic keratosis soon reappeared, as did, in one case, numerous basal cell carcinomas (BCC). However, etretinate did not prevent the occurrence of a malignant melanoma and of a few lesions of lentigo and naevus. 2. In the first case of BCN concerning two sisters, one treated the other untreated, less BCC lesions and, mainly, less BCN lesions were recorded in the sister treated than in the untreated sister. In the second case of BCN 28 BCC lesions developed while the patient was under observation without any treatment during 6 months, whereas only 31 BCC lesions had been recorded during 6 years under etretinate.(ABSTRACT TRUNCATED AT 250 WORDS)