Thalamic tumour presenting as frontal lobe dysfunction

A 64-year-old man presented with a change in personality and behaviour but with no neurological deficits. He exhibited impaired executive functions, a pathy, unsteadiness of gait and falling; he lacked insight and exhibited pu rposeless behaviour, making loud grunting noises. A CT scan at 6 months rev ealed no abnormality, but at 9 months CT and MRI showed a bilateral thalami c tumour. The presenting symptoms had similarities to frontal lobe dysfunct ion progressing to dementia.