The predictive value of protein, glucose, and lactate for a diagnosis of neoplastic meningitis.

Abstract

e12005 Background: Neoplastic Meningitis (NM) is a complication of many common cancers that occurs with an incidence as high as 15% in some cancer types. Diagnosis remains elusive with poor screening tools and insensitive diagnostic options. Methods: A retrospective analysis of 341 consecutive patients with suspected NM was undertaken. Clinical presentation, demographic, cytologic and MRI data were recorded. Using cytology as the diagnostic gold standard, sensitivity, specificity, ROC curves and likelihood ratios were calculated. Results: 210 patients met inclusion criteria, 87 with primary brain tumors (PBT), 72 with non-CNS solid tumors, and 44 with lymphomas. 111 patients were male; 123 (58.6%) ultimately had a positive cytology. Only 59% of patients with positive cytology presented with symptoms concerning for NM. 32.9% of patients with PBTs and positive CSF cytology exhibited neurologic symptoms suggestive of NM. Patients with non-CNS solid tumors and positive CSF cytology presented with symptoms concerning for NM 80% of the time. Patients with cytology-positive, MRI-positive and symptom-positive NM had very different survivals. Potentially informative CSF values are in table below. Conclusions: A definitive diagnosis for patients with suspected NM remains elusive without a positive cytology, but some clinical, radiographic, and CSF findings are useful for raising diagnostic concern, and for screening in at-risk populations. Symptom-positive or MRI-positive NM may represent different diseases than cytology-positive NM. [Table: see text]