Malignant acanthosis nigricans--a para-endocrine syndrome?

A case is reported of acanthosis nigricans associated with a gastric carcinoma. The gastric cancer was of the diffuse, infiltrating type. Many tumour cells were identified by means of histochemistry and electron microscopy as neoplastic enterochromaffin-like cells. It is suggested that cancers associated with acanthosis nigricans might constitute a certain group of carcinomas in which parts of the tumour cells arise from the APUD-series of endocrine cells.