Blood Neurofilament Light Chain Measurements in Adults with CNS Histiocytic Neoplasms
Samantha Banks1, Paul Decker2, Eoin Flanagan3, Anastasia Zekeridou4, Ronald Go3, Jithma Abeykoon3, Gaurav Goyal5, Jason Young3, Matthew Koster3, Robert Vassallo3, Jay Ryu3, Caroline Davidge-Pitts3, Aishwarya Ravindran5, Julio Sartori Valinotti3, Nora Bennani3, Mithun Shah3, Karen Rech3, Corrie Bach3, Jeanette Eckel-Passow3, W. Tobin3
1Neurology, 2Quantitative Health Sciences, Mayo Clinic, 3Mayo Clinic, 4Neuroimmunology Laboratory, Mayo Clinic, 5University of Alabama at Birmingham
Objective:
Evaluate the association between neurofilament light chain (NfL) level in adult patients with histiocytic neoplasms and the presence of CNS involvement.
Background:
NfL is an indirect measure of axonal damage, measurable in blood and CSF, and may be useful in screening for neurologic involvement, staging disease, and monitoring treatment response in histiocytic neoplasms.
Design/Methods:
27 patients with a histiocytic disorder and 39 healthy controls who were seen at Mayo Clinic Rochester and had available stored samples for NfL testing were compared.
Results:
21 patients had Erdheim Chester Disease (ECD), 4 had Langerhans cell histiocytosis (LCH), and 2 had mixed histiocytosis (ECD/ RDD, ECD/ LCH). Median age at onset was 47 years (range 19-82), 12/27 (44%) were female. BRAF V600E mutation was present in 13/23 (57%). Patients with histiocytic neoplasms had significantly higher NfL (48.1 vs 17.7 pg/mL, p<.0001) than healthy controls. Of patients with histiocytic neoplasms, patients with CNS involvement had higher NfL compared with the patients without CNS disease (63.7 vs 21.1 pg/mL, p=0.002). Those with parenchymal CNS involvement had higher NfL than those without (58.4 vs 28.8 pg/mL, p=0.04). Post gadolinium enhancing lesions on brain or spine MRI were associated with higher NfL levels (69.5 vs 28.8 pg/mL, p=0.003).
Conclusions:
Elevated blood NfL is associated with CNS involvement in histiocytic neoplasms, and is associated with active parenchymal disease. Further studies are needed to evaluate whether NfL can be used to screen for CNS involvement and monitor treatment response in patients with histiocytic neoplasms.