Solitary Tumefactive Demyelinating Lesions in Children: Clinical and Magnetic Resonance Imaging Features, Pathologic Characteristics, and Outcomes.

ABSTRACT

BACKGROUND: Isolated tumefactive demyelinating lesions (≥2 cm) may be difficult to distinguish from contrast-enhancing brain tumors, central nervous system infections, and (rarely) tissue dysgenesis, which may all occur with increased signal on T2-weighted images. Establishing an accurate diagnosis is essential for management, and we delineate our single-center experience. METHODS: We performed a retrospective review of medical records, imaging, and biopsy specimens for patients under 18 years presenting with isolated tumefactive demyelination over a 10-year period. RESULTS: Ten children (eight female) met inclusion criteria, with a median age of 14.1 years. Lesions were most likely to involve the thalamus (six of 10), brainstem (five of 10), basal ganglia (four of 10), or corpus callosum (four of 10). Eighty percent had perilesional edema at presentation, and 60% had midline shift. Biopsies demonstrated demyelination with perivascular lymphocytic infiltration and axonal damage ranging from mild to severe. All patients were initially treated with high-dose corticosteroids, and eight of 10 required additional medical therapies such as intravenous immunoglobulin, plasmapheresis, cyclophosphamide, or rituximab. Increased intracranial pressure was managed aggressively with two of 10 patients requiring decompressive craniectomies. Clinical outcomes varied. CONCLUSIONS: Solitary tumefactive demyelinating lesions are rare, and aggressive management of inflammation and increased intracranial pressure is essential. Biopsy is helpful to evaluate for other diagnoses on the differential and maximize therapies. Treatment beyond initial therapy with corticosteroids is often required. Isolated tumefactive demyelinating lesions are uncommon; multicenter natural history studies are needed to better delineate differential diagnoses and optimal therapies.