Correlation of MRI and clinical features in meningeal carcinomatosis.

Ten patients with meningeal carcinomatosis associated with nonhaematological neoplasms were examined: six with breast, two with gastrointestinal and one with lung cancer, plus one with a tumour of unknown origin. Cytology was positive in all but one. The patients were classified into four groups according to the gadolinium-enhanced MRI (Gd-MRI) appearances: group 1 had pure leptomeningeal carcinomatosis, group 2 dural carcinomatosis, group 3 spinal leptomeningeal carcinomatosis, and group 4 had normal Gd-MRI except for hydrocephalus. In group 1, Gd-MRI showed diffuse enhancement of the subarachnoid space, including the cisterns around the midbrain, the sylvian fissures, or cerebellar and cerebral sulci. In group 2, Gd-MRI showed diffuse, thick, partially nodular enhancement of the dura mater. No leptomeningeal or subependymal enhancement was evident. In group 3, nodular masses were seen only in the spinal canal. In group 4, no definite evidence of meningeal carcinomatosis was demonstrated on contrast-enhanced CT (CE-CT) or Gd-MRI. The median survival time was 2.0 months in group 1, 1.0 month in group 3, and 4.5 months in group 4, but the two patients in group 2 were alive 10 and 15 months after a definite diagnosis of meningeal carcinomatosis was made. In all patients examined by both CE-CT and Gd-MRI, the latter was superior for identification of meningeal carcinomatosis. Hydrocephalus in an important indirect sign of leptomeningeal carcinomatosis, but was not seen in patients with dural carcinomatosis despite the presence of increased intracranial pressure.