There are two types of primary brain tumors: Benign brain tumor: this type is not made up of cancer cells and can be removed without the danger of it growing back. It is very rare that benign tumor cells try to forcefully enter the neighboring tissue, neither do they go out into different body parts. However, grave health issues can come up due to them pressing down on brain areas that are very sensitive. In fact, they can prove to be life threatening as well. There is also a chance that this type could transform into a malignant brain tumor. Malignant brain tumor: this type does have cancer cells and is much more serious and life-threatening than benign brain tumor. They tend to develop at a rapid rate and also can invade the neighboring brain tissue. The cancer cells can also spread to different brain areas during the process of them breaking away from the brain tumor.