Metastasis and angiogenesis.

The relationship of angiogenesis, the growth of new blood vessels, to the process of tumour metastasis is examined. While the occurrence of angiogenesis generally is a necessary prerequisite for the formation of secondary tumours its presence is not a guarantee that cancer dissemination will occur. Novel approaches to antimetastatic therapy, using the newly formed vascular bed of tumours as the target, have produced successful results in experimental animals though such approaches have yet to be undertaken in the clinic.