Tumefactive Neurosarcoidosis (P9-5.007)

Abstract

<h3>Objective:</h3> To define and characterize tumefactive neurosarcoidosis, a unique phenotype of neurosarcoidosis distinct from the more commonly seen smaller, perivascular, subpial parenchymal lesions. <h3>Background:</h3> 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. <h3>Design/Methods:</h3> 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. <h3>Results:</h3> 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. <h3>Conclusions:</h3> 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. <b>Disclosure:</b> Dr. Bou has nothing to disclose. Dr. El Sammak has nothing to disclose. Dr. Chien has nothing to disclose. Dr. Cavanagh has nothing to disclose. Dr. Hutto has nothing to disclose.