Proto-metastatic core and comet effect: new theoretical model of the mechanism of metastasis generation

Abstract One important aspect of cancer is its capacity to generate metastasis. The mechanism by which one or several neoplastic cells escape from the primitive tumor to start the metastatic process is still a matter of discussion, hence the need to reconsider under which circumstances and conditions ‘lethal escape’ is produced. Thus we introduce two concepts: proto-metastatic core and comet effect. We maintain that only one group of cells (proto-metastatic core) could escape passively from the tumor focus when they enter the bloodstream together with other detritus. The proto-metastatic core disintegrates through friction with the blood (comet effect). There are two mechanism of metastasis. In the first, only one cell leaves the vessel joined to white blood cells as it moves through an inflamed area. The second, from the proto-metastatic core, could form venous thrombus. We believe that this new theoretical model of the etiopathology of cancer will contribute to future therapies.