Kawai Nobuyuki, Okada Masaki, Haba Reiji, Yamamoto Yuka, Tamiya Takashi
Department of Neurological Surgery, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Case Rep Oncol. 2012 May;5(2):339-46. doi: 10.1159/000339963. Epub 2012 Jul 3.
Intravascular large B-cell lymphoma (IVL) is a rare type of extranodal lymphoma with an aggressive clinical course characterized by the proliferation of lymphoma cells within the lumen of small vessels. Diagnosis is often difficult because of marked variability in clinical presentation and nonspecific laboratory and radiological findings, especially when central nervous system (CNS) symptoms are the only manifestation. Modern metabolic imaging techniques such as positron emission tomography (PET) and (1)H-magnetic resonance spectroscopy (MRS) have been reported to be useful in the diagnosis of conventional primary CNS lymphoma. We report the case of a 69-year-old man who presented with a progressive leukoencephalopathic syndrome. The patient was examined by (18)F-fluorodeoxyglucose and (11)C-methionine PET and MRS, but none of these examinations were able to show the presence of a tumor in the lesions or to clarify the tumor characteristics. Brain biopsy was the only way to obtain a definite diagnosis of IVL. The patient was treated intensively with standard immunochemotherapy but died 6 months after the diagnosis. Here, we discuss the insufficiency of modern metabolic imaging techniques, including PET and MRS, and recommend a rapid decision of brain biopsy in the diagnosis of IVL only involving the CNS.
血管内大B细胞淋巴瘤（IVL）是一种罕见的结外淋巴瘤，临床病程侵袭性强，其特征为小血管腔内淋巴瘤细胞增殖。由于临床表现差异显著以及实验室和影像学检查结果缺乏特异性，诊断往往困难，尤其是当仅以中枢神经系统（CNS）症状为唯一表现时。据报道，现代代谢成像技术如正电子发射断层扫描（PET）和氢质子磁共振波谱（MRS）对传统原发性中枢神经系统淋巴瘤的诊断有用。我们报告一例69岁男性患者，其表现为进行性白质脑病综合征。对该患者进行了氟代脱氧葡萄糖（18F-FDG）和蛋氨酸（11C-MET）PET及MRS检查，但这些检查均未能显示病变中存在肿瘤或明确肿瘤特征。脑活检是明确诊断IVL的唯一方法。该患者接受了标准免疫化疗，但在诊断后6个月死亡。在此，我们讨论包括PET和MRS在内的现代代谢成像技术的不足之处，并建议对于仅累及中枢神经系统的IVL诊断应迅速决定进行脑活检。
