Case report: An 8-month-old infant with macrocephaly was found to have hydrocephalus and a cystic third ventricular tumour; biopsy of the tumour showed a choroid plexus adenoma. The tumour was attached to the ependymal lining and was strongly adherent to the walls and floor of the anterior third ventricle.
Treatment: After biopsy, it was felt that a radical resection would carry a high risk of injury to the floor of the third ventricle and cause new neurological deficits. Therefore, an external ventricular drain was inserted and bilateral ventriculo-peritoneal shunts were inserted 1 week post-operatively. In view of the benign nature of the tumour, no adjuvant radiotherapy or chemotherapy was given.
Outcome: There was no further tumour growth or clinical deterioration over a 6-year follow-up period.