Cutaneous manifestations of visceral malignancy.

HEBRA (1868) was the first to suggest that pigmentation of the skin might indicate the presence of a visceral cancer. With gathering speed, more and more skin reactions which occur before or concurrently with malignant disease have been observed. Some suspected associations such as the presence of Campbell De Morgan angiomata, which were at one time considered harbingers of cancer, are now recognized as incorrect. The more recent example of such negative evidence is the report (Rhodes, 1970) that seed keratoses on the palms and soles thought by Dobson, Young & Pinto (1965) to occur four times as frequently in patients with cancer, affect 62%4 of skin patients over 40 and indicate no greater proneness to internal neoplasia. Many skin changes occur in elderly people in the cancer age and it is important therefore to avoid ascribing normal aging effects or even skin disorders of old age to internal carcinoma when the relationship may only be coincidental. There are, however, many very striking associations between skin lesions and visceral cancer but it is easier to observe them in the rare disorders such as acanthosis nigricans or the sudden sprouting of lanugo hair over the face of an adult (Lyle & Whittle, 1951) than in the everyday complaints of generalized pruritus or urticaria. Unfortunately by the time skin lesions such as acanthosis nigricans have appeared the underlying neoplasm is far advanced and there is no opportunity to alter the natural course of the disease. It is particularly important, therefore, to recognize those conditions which may indicate the precancerous state such as the genetic defect of an internal organ which may develop a neoplastic change at an early age.