Angiogenesis is derived from the word "angio" meaning blood and "genesis" meaning new.

Tumor angiogenesis is the growth of blood vessels from surrounding tissue into a solid tumor. Researchers believe this is caused by the release of chemical substances by the tumor.

References

National Cancer Institute Website. Last accessed 4/14/06. http://www.cancer.gov/Templates/db_alpha.aspx?CdrID=46529. Burri, P. H., Hlushchuk, R., & Djonov, V. Intussusceptive angiogenesis: Its emergence, its characteristics, and its significance. Devel Dynam 231: 474-488, 2004.