Myelography for staging medulloblastoma.

Thirty-eight patients with newly diagnosed medulloblastoma were studied with myelography and cerebrospinal fluid (CSF) cytology studies before radiotherapy. Seventeen (45%) patients had evidence of dissemination beyond the posterior fossa. Spinal cord lesions were demonstrated in ten patients (26%). Negative results of CSF cytology studies did not preclude demonstration of cord involvement. Children younger than 5 years were more likely than older patients to have spinal cord involvement at diagnosis. Patients who were truly M-0 did better in terms of absolute survival but not relapse-free survival when compared with patients with dissemination. Myelography and cytology studies are necessary in the evaluation of all newly diagnosed patients with medulloblastoma and may also be indicated for patients with other brain tumors with a known propensity for dissemination.