Tumor growth and metastasis depend on angiogenesis (creating new blood supply) and lymphangiogenesis (creating new lymphatic supply) triggered by chemical signals from tumor cells in a phase of rapid growth. The cancer cells without blood circulation grew to 1–2 mm3 in diameter and then stopped, but grew beyond 2 mm3 when placed in an area where angiogenesis was possible. In the absence of vascular support, tumors may become necrotic or even apoptotic. Follow us @medshots for more shots