[Carcinomatous meningitis. Presentation of 3 cases].

Meningeal carcinomatosis is characterized by diffuse infiltration of the leptomeninges by metastatic cancer in patients usually with a previous history of malignancy. Primary tumors are adenocarcinomas of the breast or lung, or malignant melanoma. The clinical presentation is pleomorphic and commonly affects the cerebral hemispheres, the cranial nerves, or spinal cord and its roots. Diagnosis is confirmed by the presence of the malignant cells in the cerebrospinal fluid (CSF). Computed tomography (CT) and magnetic resonance (MRI) show abnormal findings including ventricular dilatation and small enhancing lesions along the CSF space. Despite radiotherapy and chemotherapy, vital prognosis remains bad and the treatment is useful in improving the quality of life. Three cases presented here emphasize once again the important fact that meningeal carcinomatosis remains a very difficult diagnosis; several lumbar punctures were sometimes necessary, and cerebral fluid studies cannot yet be replaced by other diagnostic techniques like contrast enhanced CT or MRI with gadolinium.