Evidence for the Antimetastatic Effects of Coumarin Derivatives

Abstract

The first morphological evidence for an association of intravascular cancer cells with thrombotic material was found at the beginning of this century (1). However, not until more than 50 yr later was the possible pathogenic significance of this phenomenon recognized. Observing the fate of intravascular tumor cells in vivo in the Hopkins rabbit ear chamber, Wood (2) found that a tumor cell embolus was rapidly surrounded by microthrombi shortly after its initial attachment to the vascular endothelium. By time-lapse cinematography the investigator was able to document how these intravascular cancer cells, sheltered by their surrounding thrombus, penetrated the vessel wall into the perivascular tissue where they started to proliferate into a “secondary” tumor. From these observations Wood concluded that the activation of the coagulation system at the site of tumor cell lodgment was of significance in the initial phase of the hematogenous spread of malignant tumors.