For one man, the first sign came when he mixed up words while ordering lunch in a restaurant. For a little girl, it began with a loss of balance and changes in hearing. In both cases, the mysterious symptoms were caused by a brain tumor.
Primary brain tumors (tumors that begin in the brain) are relatively rare. There are more than 120 different kinds, and they can be either malignant (cancerous) or benign (not cancerous).