In a number of skin disturbances conditioned or aggravated by sunlight and/or mainly diffused to the cutaneous connective tissue (present acquired pellagra, lupus erythematosus, porphyria cutanea tarda, actinic reticuloid, Rothmund-Thomson syndrome, lymphocytoma cutis, scleroderma, dermatomyositis,
Thirty-five cases of benign parapsoriasis en plaques, 24 cases of prereticulotic poikiloderma (3 of which were in evolution towards polymorphous lymphomas), 15 cases of lymphoma and 10 cases of other various skin proliferative disorders were studied. For various reasons the first two conditions are