Cerebellar medulloblastoma: the importance of posterior fossa dose to survival and patterns of failure.
Fifty patients with biopsy-proven cerebellar medulloblastoma were retrospectively analyzed for prognostic factors, survival and patterns of failure. Five- and ten-year actuarial survivals for the entire group were 51% and 42%. Survival and local control were significantly better for the 21 patients who received doses greater than 5000 rad to the posterior fossa (85% and 80% respectively) than for the remaining patients (38% and 38%, respectively). Significant prognostic factors included achievement of local control in the posterior fossa (p = .0001) and dose to the posterior fossa (p = .0005). Sex, age, duration of symptoms, extent of surgery and initial T-stage of disease were not significant. Posterior fossa was the predominant site of failure (71% of failures), but 10% of patients failed in the cerebrum and 12% outside the CNS. This experience confirms that survival rates of 70-80% are achievable with current treatment policies but accurate and consistent dose delivery to the posterior fossa is essential.
D000293:Adolescent; D002528:Cerebellar Neoplasms / Q000532:radiotherapy*; D002648:Child; D002675:Child, Preschool; D003388:Cranial Fossa, Posterior; D005260:Female; D006801:Humans; D008297:Male; D008527:Medulloblastoma / Q000532:radiotherapy*; D009364:Neoplasm Recurrence, Local; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D012189:Retrospective Studies