Cerebrospinal fluid M staging for medulloblastoma: reappraisal of Chang's M staging based on the CSF flow.
Tumor seeding is a strong negative prognostic factor for patients with medulloblastoma. Because Chang's M staging is based primarily on CT and myelographic findings and might be contradictory to the direction of normal cerebrospinal fluid (CSF) flow, seeding patterns and appropriate staging of medulloblastoma need to be revisited in patients diagnosed in the MRI era. We retrospectively reviewed the clinical and radiological data of 86 patients with a diagnosis of medulloblastoma who were treated in the MRI era. The presence of seeding in each subarachnoid space compartment and the patterns of seeding were analyzed in correlation with patient survival data. Thirty-four patients had gross seeding on perioperative MRI. Thirty-two patients had seeding in the spinal compartment. Sixteen and 12 patients had seeding in the infratentorial and supratentorial compartments, respectively. There was an apparent hierarchy of seeding (ie, from seeding in the spinal compartment up to the supratentorial compartment). Patients with seeding in the spinal compartment had longer progression-free survival (P = .038) and a tendency toward better overall survival (P = .053) compared with patients with seeding in intracranial compartments. We modified Chang's M staging based on the CSF flow and termed this approach "CSF M staging." CSF M staging for medulloblastoma, in which intracranial seeding occupies a higher rank than spinal seeding, was a better predictor of patient prognosis. This modified staging method may be applied to metastatic staging of brain tumors located in the fourth ventricle.
Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, 101 Daehangno, Jongno-gu, 110-744 Seoul, South Korea.
Ji Hoon
JH
Phi
Joongyub
J
Lee
Kyu-Chang
KC
Wang
Byung-Kyu
BK
Cho
In-One
IO
Kim
Chul-Kee
CK
Park
Chae-Yong
CY
Kim
Hyo Seop
HS
Ahn
Il Han
IH
Kim
Seung-Ki
SK
Kim
D000293:Adolescent; D000328:Adult; D002528:Cerebellar Neoplasms / Q000134:cerebrospinal fluid* / Q000473:pathology* / Q000628:therapy; D002555:Cerebrospinal Fluid / Q000166:cytology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D008527:Medulloblastoma / Q000134:cerebrospinal fluid* / Q000473:pathology* / Q000628:therapy; D009367:Neoplasm Staging; D011379:Prognosis; D055815:Young Adult