Atheroma as a neoplastic disease

An hypothesis is proposed that atheroma may be classified as a leiomyosarcoma derived from the tunica media of an artery. The notion that atheroma is a neoplastic disease provides a simple explanation for a highly complex phenomenon; the pathogenesis of artherosclerosis. According to this hypothesis some smooth-muscle cells in the media undergo malignant transformation, which is manifested by excessive production of hyaluronidase and other glycosaminoglycan hydrolases. This enzymic system frees cells from their bonds and allows them to proliferate. The enzymes also evoke a fibroblast hyperplasia which is followed by a protective collagenization producing a local area of increased resistance to the hydrolases. This accounts for the sclerosing aspect of the disease. Several other features of atherosclerosis are a result of the neoplastic nature of the disease.