[Bilateral thalamic tumours. Three case reports and a review of the literature]. / Tumores talámicos bilaterales. Presentación de tres casos y revisión de la bibliografia.

INTRODUCTION: Thalamic tumours account for approximately 1% to 5% of all brain tumours, and are usually unilateral astrocytoma and frequently affect children. Bilateral thalamic tumours are very rare neoplasm, yet their actual incidence is unknown. AIMS: To report three children with bilateral thalamic tumours diagnosed in a 20 years period and to review the previously reported cases. CASE REPORTS: Here we report three children with bilateral thalamic tumours and review the previously reported cases diagnosed by angiography, computed tomography, and or magnetic resonance imaging. Twenty-six patients with bilateral thalamic tumours were analysed (13 children and 13 adults). Symptoms of mental impairment were present in 13 cases (50%) and sings of intracranial hypertension in 7 (26.9%). The pathology was confirmed in 22 patients (12 low grade gliomas and 10 high grade gliomas). In paediatric age there was a slight preponderance of low grade gliomas (7/12). The mean survival is 12.3 months (range: 7-36 months). CONCLUSIONS: Bilateral thalamic tumours are exceptional and have radiological and clinical features that differ from those of unilateral thalamic tumours. Today, the main role of surgery is still to obtain a histological diagnosis. The outcome of treatment for bilateral thalamic tumours remains poor, with only 7.6% of all patients surviving for more 12 months.