Gliomatosis cerebri is so rare that most doctors have never seen it – it’s important that you take your child to a major medical center where the neuroscience team has experience with rare brain tumors. At Weill Cornell Medicine Dr. Greenfield is one of the world’s pre-eminent experts on gliomatosis cerebri and collaborates with a consortium of 20 other institutions around the world in the hopes of better characterizing this rare tumor. (See Doctors Who Treat Gliomatosis Cerebri.)