If a tumor starts to grow and it doesn't develop a vascular supply it doesn't develop blood vessels in it, then it can't get bigger than a certain size and there's lots of evidence from many cancers showing that this is true.

如果肿瘤生长时,没有形成新的血管以维持供血,肿瘤内部也没有血管的话,它的大小将非常有限,这一结论已有许多科学成果可以证明

耶鲁公开课 - 生物医学工程探索课程节选