Primary central nervous system lymphoma (PCNSL) is rare. And the symptoms of PCNSL are atypical, it is extremely easy to be misdiagnosed as other diseases. However, early treatment is crucial which is requesting early diagnosis. We report a case of a 47-year-old man who was initially diagnosed as neuromyelitis optica (NMO) on the basis of clinical findings, slightly high Aquaporin4 (AQP4) (1:10) and high signals of magnetic resonance imaging. Though his symptoms progressively improved after steroid pulse treatment, but worse when steroid was decreased to 40 mg per day. We considered the patient should be diagnosed as PCNSL. After the examination of magnetic resonance spectroscopy (MRS) and positron emission tomography (PET), the results indicated PCNSL was most possible. Therefore we gave him stereotactic biopsy of deep of supratentorial, which showed non-Hodgkin malignant B-cell lymphoma.

中文翻译：

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一例原发性中枢神经系统淋巴瘤模拟视神经脊髓炎

原发性中枢神经系统淋巴瘤（PCNSL）很少。而且PCNSL的症状不典型，与其他疾病一样容易被误诊。但是，早期治疗至关重要，因此需要早期诊断。我们报告了一例47岁的男子，该男子最初根据临床发现被诊断为视神经脊髓炎（NMO），Aquaporin4（AQP4）稍高（1:10）和磁共振成像的高信号。尽管类固醇脉冲治疗后他的症状逐渐改善，但当类固醇减少至每天40 mg时，症状会恶化。我们认为患者应被诊断为PCNSL。对磁共振波谱（MRS）和正电子发射断层扫描（PET）进行检查后，结果表明PCNSL最有可能。因此，我们给他做了深部幕上的立体定向活检，