[Bilateral thalamic tumours. Three case reports and a review of the literature]

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.

To report three children with bilateral thalamic tumours diagnosed in a 20 years period and to review the previously reported cases.

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).

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.