Chang score

Cerebellar medulloblastoma

Tumor stage (T)

T1: tumor diameter <3cm, involving one structure in posterior fossa

T2: tumor diameter <3cm, involving two or more structures posterior fossa structures

T3a: tumor diameter >3cm, involving two or more structures posterior fossa structures

T3b: tumor involving floor of the 4th ventricle

T4: tumor spreading out of the 4th ventricle or presence of severe hydrocephalus

Metastasis (M)

M0: no tumor cells in cerebrospinal fluid (CSF)

M1: presence of tumor cells on CSF cytology

M2: tumor seeding in intracranial CSF pathways

M3: tumor seeding in spinal CSF pathways

M4: systemic spread

Neurosurgery Case Review. Editors: R Nader, AJ Sabbagh. Thieme Medical Publishers, Inc. 2010