Researchers have discovered that primary tumors can prevent the growth of secondary tumors by sending the immune system after them.

Cancer is bad enough in one spot, but the disease gets especially dangerous once it starts migrating throughout the body. Finding ways to stop this process, known as metastasis, is a key way to improve survival rates for patients. Now researchers have found that primary tumors have their own mechanism for slowing the growth of secondary cancers, which could be tapped into as a new potential treatment option.