Medulloblastoma of the cerebellopontine angle in adulthood

Cerebellar medulloblastoma is a rare malignant tumour that represents 25% of all intracranial tumours in the first 10 years of life, but only 1.1% of CNS tumours (male:female ratio 2:1) in adults. In 67-93% of the cases in childhood, medulloblastoma involves the median line of the cerebellar parenchyma. In contrast, almost 70% of the cases in adulthood are paramedian or lateral. The site of lesion may cause difficulty in reaching a diagnosis. MRI thus does not give a clear interpretation of the type of lesion. In addition, clinical medicine is not of particular help in distinguishing the various lesions that occur in the same areas. It should be stressed that the characteristics of medulloblastoma in adults are more variable than those in children and, therefore, should be included in the differential diagnosis of posterior cranial fossa lesions. We report a new case of medulloblastoma in the CPA in an adult and discuss the difficulties concerning its diagnosis and treatment.