Tumefactive Neurosarcoidosis
Gabriela Bou1, Sally El Sammak3, Ling-Chen Chien2, Julien Cavanagh3, Spencer Hutto4
1Neurology, Emory University, 2Radiology, Emory University, 3Emory University, 4Emory University: Neurology Residency Program
Objective:

To define and characterize tumefactive neurosarcoidosis, a unique phenotype of neurosarcoidosis distinct from the more commonly seen smaller, perivascular, subpial parenchymal lesions.  

 

Background:
Enhancing brain parenchymal disease is an uncommon manifestation of neurosarcoidosis (10-27%). Intraparenchymal tumefactive lesions are even rarer (6-8%). As no studies dedicated to tumefactive lesions have been published, their clinical characteristics and impact on management and outcomes are unknown.  
Design/Methods:
Patients were included if: 1) lesions were within brain parenchyma, 2) the lesion’s largest dimension was greater than 1 cm, 3) perilesional edema and/or mass effect were present, and 4) sarcoidosis was confirmed by neural or extraneural biopsies. 
Results:
Nine patients were included with a median age of 37 years. Pathological confirmation came from brain parenchymal biopsies in 5 (55.6%) and extraneural tissues in the remainder. Isolated neurosarcoidosis was seen in 1 patient (11.1%). Only 1 patient (11.1%) was known to have systemic sarcoidosis previously at the time the parenchymal mass was evaluated. Median modified Rankin scale (mRS) score at nadir was 2 (range 1-4). Common manifestations included headache (77.8%), cognitive dysfunction (55.6%), and seizures (44.4%). MRI characteristics included spherical morphology (77.8%), perilesional edema (100.0%), mass effect (55.6%), well-demarcated lesions (66.7%), and contrast enhancement (100.0%; 55.6% inhomogeneous). The frontal lobe (44.4%) was most commonly affected, followed by the subinsular region (22.2%), putamen (22.2%), and internal capsule (22.2%). Leptomeningitis was a frequent neuroinflammatory accompaniment (77.8%). All patients received steroids and required steroid-sparing treatments. 55.6% of patients required second- and third-line treatments. Infliximab was needed in 44.4%. After a median follow-up period of 86 months, the median last mRS was 1.0, with significant residual deficits in 44.4% of patients.  
Conclusions:
Tumefactive neurosarcoidosis most commonly affects the supratentorial brain in patients without a known history of sarcoidosis, is typically associated with leptomeningitis, and often is refractory to initial treatments.
10.1212/WNL.0000000000202699