Quantification of cerebrospinal fluid ferritin as a biomarker for CNS malignant infiltration.

Several markers have been studied for their ability to make the CNS infiltration diagnosis earlier and more precise; previous studies showed that CSF ferritin concentrations were higher in patients with malignant invasion of CNS. The objective was to determine the importance of CSF ferritin as a biomarker for the diagnosis of CNS neoplastic infiltration. This study is based on 93 CSF samples, divided into five groups: malignant cells present (n13); malignant cells not present (n26); inflammatory neurological diseases (n16); neurocysticercosis (n20); acute bacterial meningitis (n18). CSF ferritin values were determined by micro particle enzyme immunoassay. CSF ferritin level (mean+/-SD) in the group with neoplastic cells in the CSF was 42.8+/-49.7 ng/mL, higher than in the other groups (p<0.0001). We conclude that CSF ferritin with the cut off 20 ng/mL could be an adjuvant biomarker to the diagnosis of CNS malignant infiltration.