Introduction: Carcinomatous meningitis reveals a solid cancer in 10 percent of cases.
Observation: Our patient developed isolated headache which progressively worsened. Cranial Computerized Tomography (CT) was normal. Brain MRI showed multiples areas of contrast enhancements meningeal tissue associated with small nodulars deposits. Repeated cerebrospinal fluid (CSF) examinations revealed elevated tumor markers suspect cells. The diagnosis of pulmonary adenocarcinoma was established during systematic follow-up.
Conclusion: The diagnosis of carcinomatous meningitis can be difficult to establish because of the non-specific clinical presentation and the absence of suggestive context; negative CSF-cytology is frequent. MRI and elevated tumor markers in the CSF compared with the serum level contribute significantly to diagnosis.