Histopathological Analysis of Posterior Fossa Tumor

ABSTRACT

The posterior fossa, containing roughly 6ne fourth of the intracranial contents, is the site of about 30-35% of the intracranial tumors. The incidence of primary tumors in the posterior fossa is quite different from that of the cerebivm. We analysed 124 cases of posterior fossa tumor, over a 10 year period, to understand the status of posterior fossa tumor and its histologic characteristics. Medulloblastoma was most common(37cases, 29.8%), followed by astrocytoma, hemangiobla-stoma, ependymoma, meningioma, metastatic tumor, arteriovenous malformation and choroid plexus papilloma in descending order of frequency. Tumors were found most frequently between the ages of two and ten years(28.2%) and sixty seven(54.0%) cases were diagnosed before the age of fifteen. The ratio of male to female was 60 64. Astrocytoma revealed a characteristic juvenile pilocytic type and a microcystic change. Hemangioblastoma showed higher frequency(17.7%) than previous reports and the origin of tumor cells is still equivocal. Other tumors revealed the same histologic features as other intracranial tumors.