Adult medulloblastoma: clinical profile and treatment results of 18 patients.

The objective of this article is to examine the clinicoradiological features and surgical outcomes of adult patients (>16 years) with medulloblastoma. An attempt was made to identify the predictors of poor outcome and assess patterns of relapse and to compare these with pediatric medulloblastoma. Retrospective case record analyses were performed on 18 adults (>16 years) and 79 children (<16 years) operated upon after January 1990, who had at least 5 years of follow-up. The following variables were assessed by bivariate analyses: age, location of the lesion, brainstem invasion, extent of excision and histological subtype. Statistical analysis was performed using chi-square test, Fischer's exact test and Student's t-test. Results revealed there was no gender preference. The tumor was located in the vermis in 12 patients (66.6%) and in the cerebellar hemisphere in six (16.6%). Calcification was observed in two cases (11.1%) and hydrocephalus was seen in six (33.3%). MRI evidence of brainstem infiltration was seen in three patients (16.6%). Total excision was achieved in 13 cases (72.2%), near total excision in four (22.2%) and subtotal excision in one. Major complications included fresh cranial nerve deficits in four patients (22.2%), hemiparesis and gait unsteadiness in three (16.6%), mutism in one and meningitis in two. All patients underwent adjuvant radiotherapy in the form of craniospinal irradiation with a posterior fossa boost. On follow-up, 11 patients (61.1%) were observed to have recurrence and all were located in the posterior fossa. All 11 subsequently underwent chemotherapy. Two patients had re-operation for residual/recurrent lesions causing raised intracranial symptoms. Five-year follow-up data showed that 10 patients (55.5%) were alive, five (27.7%) had died while three (16.6%) were lost to follow-up. In spite of recent advances in management, patients with medulloblastoma still have a poor prognosis. However, adults fared better than children. Vermian location had a better outcome in adults, but not in children. Desmoplastic variant histology was not observed to be a significant prognostic factor in the adult group while brain stem invasion carried a poor prognosis.