PNET tumors appear identical to medulloblastoma under the microscope; however, this tumor occurs in the cerebrum versus the cerebellum.  The cerebrum controls thought, movement and sensation.  PNET tumors are highly malignant and tend to spread throughout the central nervous system as tumor cells travel through the cerebrospinal fluid to the spine.

Symptoms of PNET tumors include "morning sickness", headache, nausea, vomiting, fatigue, lethargy, double-vision, disturbances in ocular movement, back and/or leg pain, slow developing weakness of the lower extremities and incontinence.

The five-year survival rate for children diagnosed with PNET tumors is 50% - 60%; however, relapse cases are almost always fatal.