As the tumor grows in size, it may invade surrounding or distant tissues.
If cancer cells break off from the primary tumor they may travel to distant sites in the body, invading vital organs such as the brain, bone, liver or lung, and establish new tumors. When these vital organs fail, it can be fatal.
That is why early detection and treatment are so important. It increases the chances of removing the tumor when it is small, before it has grown and invaded other tissues.