["Superficial spreading melanoma" within a psoriasis focus as a delayed sequela following arsenic therapy for psoriasis].

After a longlasting psoriasis (25-30 years) and after an arsenotherapy of psoriasis per os fifteen years ago an arsenic-caused injury occured with formation of a melanoma within the surrounding psoriasis. In examinating comparable Moselle vine dressers with late arsenic-caused injuries during the years 1972-1975, altogether 1600 examinations, precancerosis, basaliomas, morbus-Bowen, spinaliomas, and transitional epithelium carcinomas have been found and have been histologically confirmed. No melano malignom has been found. Al in eleven other cases of vine dressers with arsenic-caused late injuries showing keratosis, precancerosis, and basaliomas together with a long-lasting psoriasis vulgaris no melano malignom has been found.