Cardiac Myxoma. A morphologic and histogenetic appraisal

A histologic study of 31 cardiac myxomas has shown a consistent cell type and growth pattern differing from that seen in thrombi and other cardiac neoplasms. Exaggerated proliferation of the myxoma cells and their polysaccharide production are believed to be the source of the epithelium‐like and gland‐like tissue as well as the polysaccharide rich stroma found in cardiac myxomas. Light‐microscopic, enzyme histo‐chemistry and electron‐microscopic studies support a neoplastic endocardial cell origin for the cardiac myxoma.