Cancer and Blood Vessels: A Complex Relationship.

Abstract

The relationship between vessels and cancer has been the subject of many studies. In 1787 was formulated the idea that tumors always induced growth of new vessels, a phenomenon called angiogenesis. The growth of new capillaries into tumor implants was formally described in animal models only in 1939 but during the same years was also published that only pre-existing vessels could be identified inside some neoplastic lesions. During the 1970s, Folkman started to systematically investigate the role of newly formed vessels in cancer and the angiogenesis theory, i.e. the complete reliance of cancers on new vessels in order to grow, become predominant. Eventually recent work has demonstrated that some tumors can truly grow without inducing angiogenesis as the neoplastic cells exploit the preexisting vessels by co-opting them.