Intrinsic tectal low grade astrocytomas: is surgical removal an alternative treatment? Long-term outcome of eight cases.

Low-grade gliomas arising in dorsal midbrain in children and young patients usually present few neurological symptoms and findings, and patients management is controversial. Some authors propose only clinical observation until the patient present signs of increased intracranial pressure when a shunt with or without biopsy, is inserted; others recommend radiotherapy after stereotactic or open biopsy. Microsurgical total removal of tumor may be curative. We present a retrospective analysis of eight patients (mean age 16.6 +/- 11.5 years-old) with low-grade astrocytoma of the tectal region operated on using an infratentorial/supracerebellar approach between 1981 and 2002. All patients presented hydrocephalus and had a shunt insertion before surgical resection of the lesion. The tumour could be totally resected in seven patients. In one case radical removal was not possible due to infiltrative pattern of the lesion. Postoperative radiotherapy was performed in two cases, one patient at the beginning of this series and in the case with infiltrative tumor. This patient presented progressive tumor growth and died five years after surgery. No recurrence occurred after total removal. Post-surgical follow-up time ranged from 2 1/2 to 22 1/2 years (mean 9.9 +/- 5.9 years). Radical microsurgical removal of non invasive tumors is possible without mortality or significant morbidity. It may be curative and should remain as an alternative to be discussed with the patient.