title: Central nervous system lymphoma initially diagnosed as tumefactive multiple sclerosis after brain biopsy.
abstract: A 72-year-old man was admitted with left homonymous hemianopsia and hemiparesis. Magnetic resonance imaging revealed a heterogeneously enhanced lesion in the right parietal lobe. A brain biopsy showed acute demyelination without malignancy, which led to a diagnosis of tumefactive multiple sclerosis (MS). The patient received corticosteroid therapy and experienced clinical and radiological improvement. Six months later, new lesions appeared, and a second biopsy revealed proliferation of dysplastic lymphocytes. This led to a revised diagnosis of primary central nervous system lymphoma (PCNSL). Because PCNSL mimics MS both clinically and radiologically, PCNSL is difficult to diagnose. Performing repeated brain biopsies may therefore be required when PCNSL is strongly suspected.
authors: Department of Neurology and Cerebrovascular Medicine, Saitama Medical University International Medical Center, Japan. yooe@saitama-med.ac.jp
authors: Yasuko
authors: Y
authors: Ohe
authors: Takeshi
authors: T
authors: Hayashi
authors: Kazuhiko
authors: K
authors: Mishima
authors: Ryo
authors: R
authors: Nishikawa
authors: Atsushi
authors: A
authors: Sasaki
authors: Hiroshi
authors: H
authors: Matsuda
authors: Akira
authors: A
authors: Uchino
authors: Norio
authors: N
authors: Tanahashi
mesh_terms: D000368:Aged; D001706:Biopsy; D001921:Brain / Q000473:pathology*; D001932:Brain Neoplasms / Q000473:pathology*; D003951:Diagnostic Errors; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology*; D008297:Male; D009103:Multiple Sclerosis / Q000473:pathology*