A case of acanthosis nigricans—an investigative approach

A patient with acanthosis nigricans secondary to a metastatic jejunal adenocarcinoma is described. An attempt was made to define the basic epidermal defect and to examine such possible influences as somatotrophin, epidermal growth factor, intestinal peptides and insulin receptors. No evidence to support a hyperproliferative epidermal mechanism was found and the hormonal profile was normal. However, there was an increase in circulating α-MSH and this may have contributed to the pigmentation seen in this patient.