Clinical Study Neoplastic Meningitis: How MRI and CSF Cytology Are Influenced by CSF Cell Count and Tumor Type

Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Although CSF cytology and MRI are standard methods to diagnose neoplastic meningitis (NM), this complication of neoplastic disease remains difficult to detect. We therefore reevaluated the sensitivity of gadolinium (GD)-enhanced MRI and cerebrospinal-fluid (CSF)-cytology and the relevance of tumor type and CSF cell count.Methods. We retrospectively identified 111 cases of NM diagnosed in our CSF laboratory since 1990 with complete documentation of both MRI and CSF cytology. 37 had haematological and 74 solid neoplasms. CSF cell counts were increased in 74 and normal in 37 patients. Results. In hematological neoplasms, MRI was positive in 49 % and CSF cytology in 97%. In solid tumors, the sensitivity of MRI was 80 % and of cytology 78%. With normal CSF cell counts, MRI was positive in 59 % (50 % hematological, 72 % solid malignancies) and CSF cytology in 76 % (92 % in hematological, 68 % in solid neoplasms). In cases of elevated cell counts, the sensitivity of MRI was 72 % (50 % for hematological, 83 % for solid malignancies) and of CSF cytology 91 % (100 % for haematological and 85 % for solid neoplasms). 91% of cytologically positive cases were diagnosed at first and another 7 % at second lumbar puncture. Routine protein analyses had