Magnetic resonance imaging of fourth ventricular choroid plexus neoplasms in childhood. A report of two cases.

Choroid plexus neoplasms (CPN) are rare tumors occurring with a relative incidence of 0.5% of intracranial neoplasms in all age groups and 1.5-6.4% of all pediatric brain tumors. In children, the most common site of origin is the atria of the lateral ventricles where the CPN may represent either a carcinoma or a benign papilloma. CPN arising in the fourth ventricle are more common in adults, and are more likely to represent a benign papilloma. We present 2 children with CPN arising from the inferior fourth ventricle with similar features on MRI, one of which represented a benign papilloma and the other a malignant carcinoma. CPN should be included, even in young children, in the differential diagnosis of any infratentorial, intraventricular tumor.