A 24-year-old woman with neurofibromatosis presented with a 1.5-year history of pain in the neck, both shoulders and back, and a 4-month history of progressively increasing weakness of all the limbs and inability to walk. The limb weakness fluctuated and, at the height of the weakness, it was associated with hesitancy and retention of urine. Magnetic resonance imaging (MRI) showed a fusiform enlargement of the upper cervical cord with obliteration of the subarachnoid space. Imaging after gadolinium-DTPA injection revealed inhomogeneous enhancement extending from the lower medulla down to the C4 cord level, and homogeneous enhancement at D3 to D4 and D6 to D8 cord levels. The spinal cord at the lower two levels appeared morphologically normal. At operation the fusiform enlargement of the cervical cord was confirmed. The tumour was partially removed. Histology revealed it to be a fibrillary astrocytoma.