MONDO_0009837 (choroid plexus papilloma) can be described as follows. Papilloma of the choroid plexus is a rare benign type of choroid plexus tumor, accounting for 1% of all brain tumors, often occurring in the fourth ventricle (in adults) and the lateral ventricle (in children) but sometimes arising ectopically in the brain parenchyma, and presenting with nausea, vomiting, papilledema, abnormal eye movements, as well as enlarged head circumference, seizures and gait impairment due to an increase in intracranial pressure. Also known as: choroid plexus papilloma, no ICD-O subtype, papilloma of the choroid plexus.