Acanthosis nigricans, a striking pigmentary disorder of the skin, has been the subject of numerous reports and reviews1since its first independent descriptions by Pollitzer and Janovsky, in 1890. There are over 260 cases on record, and it is undoubtedly true that a number of cases have been overlooked, particularly ones in which the condition is associated with a malignant growth, the significance of which overshadows the changes in the skin. The disease is characterized clinically by hyperpigmented patches varying from yellow to black, symmetrically distributed in the natural folds of the skin. There is exaggeration of the normal cutaneous markings with hyperkeratosis and verrucous and papillomatous changes. Classification of the disease has been based on the age of the patient. The juvenile or benign type occurs in persons under 20 years of age and is rarely associated with malignant disease. Although the cause of acanthosis nigricans remains obscure,