Angiogenesis in Endocrine Neoplasms

Angiogenesis promotes the growth of tumors, because it both facilitates oxygenation and nutrient flow, and removes metabolic waste. During the past two decades, as the importance of tumor vascularity became recognized, angiogenesis and the relationship between blood vessels and tumor progression received increasing attention. It was found that isolated tumor tissues failed to expand beyond few millimeters unless vascularized, whereupon vascularization they exhibited a rapid growth. Extensive research focusing on the relationship between tumor proliferation and the formation of new vessels has initially been undertaken to assess the role of angiogenesis in the progression of breast carcinomas. Significant results emerged from these investigations, and similar studies were extended to other tumor types, such as melanomas, cervical and pulmonary carcinomas, and so on. It is of note that angiogenesis as it relates to endocrine tumors has so far been limited to pituitary neoplasms, thyroid carcinomas, and pheochromocytomas. The purpose of the article is to provide a brief review of angiogenesis and to summarize available data regarding its role in the growth off endocrine neoplasms.