Miyata-Takata Tomoko, Takata Katsuyoshi, Kato Seiichi, Hu Lei-Ming, Noujima-Harada Mai, Chuang Shih-Sung, Sato Yasuharu, Maeda Yoshinobu, Yoshino Tadashi
Department of Pathology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
Department of Pathology and Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan.
Histopathology. 2017 Aug;71(2):287-295. doi: 10.1111/his.13223. Epub 2017 May 12.
The central nervous system (CNS) is a rare primary site of non-Hodgkin lymphoma. Although direct invasion of nasal natural killer (NK)/T cell tumours into CNS is reported occasionally, primary CNS NK/T cell lymphoma is extremely rare, and the clinicopathological features of primary CNS NK/T cell lymphoma remain largely unknown.
We identified four cases from our consultation files and analysed the clinicopathological features. Three were immunocompetent and one was immunosuppressed. There were three males and one female and their ages ranged from 21 to 77 years (median: 46 years). Radiotherapy was rendered for all patients, and methotrexate was administered to two patients. The overall survival was 4-29 months (median, 19 months) for the three immunocompetent patients. Neoplastic cells exhibited medium to large atypical nuclei. Angiocentric growth and necrosis were observed. The immunophenotype was typical of NK cell tumours: CD3ε, 100%; CD56, 67%; CD5, 50%; cytotoxic molecules, 100%; Epstein-Barr virus encoded small RNA (EBER), 100% and T cell receptor (TCR)-β or γ, 0%. No TCR-gene rearrangements were detected. Reviewing 10 additional cases from the literature and comparing with extranasal NK/T cell lymphoma of the more frequent origins (skin or gastrointestinal tract), primary CNS NK/T cell lymphoma was diagnosed at an earlier stage without B symptoms but exhibited aggressive clinical behaviours.
Although extremely rare, primary CNS NK/T cell lymphoma does occur and should always be included in the differential diagnosis and we should apply relevant markers routinely in conjunction with exploring the patient background. The accumulation of cases is indispensable to establish an effective treatment strategy for this rare and aggressive malignancy.
中枢神经系统（CNS）是非霍奇金淋巴瘤罕见的原发部位。尽管偶尔有报道鼻型自然杀伤（NK）/T细胞肿瘤直接侵犯中枢神经系统，但原发性中枢神经系统NK/T细胞淋巴瘤极为罕见，其临床病理特征仍 largely 未知。
我们从会诊档案中识别出4例病例并分析其临床病理特征。3例免疫功能正常，1例免疫抑制。3例男性，1例女性，年龄范围为21至77岁（中位数：46岁）。所有患者均接受了放疗，2例患者接受了甲氨蝶呤治疗。3例免疫功能正常患者的总生存期为4至29个月（中位数，19个月）。肿瘤细胞表现出中到大的非典型核。观察到血管中心性生长和坏死。免疫表型为NK细胞肿瘤的典型表现：CD3ε阳性率100%；CD56阳性率67%；CD5阳性率50%；细胞毒性分子阳性率100%；爱泼斯坦-巴尔病毒编码小RNA（EBER）阳性率100%，T细胞受体（TCR）-β或γ阳性率0%。未检测到TCR基因重排。回顾文献中另外10例病例并与更常见起源部位（皮肤或胃肠道）的鼻外NK/T细胞淋巴瘤进行比较，原发性中枢神经系统NK/T细胞淋巴瘤诊断时分期较早，无B症状，但表现出侵袭性临床行为。
尽管极为罕见，但原发性中枢神经系统NK/T细胞淋巴瘤确实存在，应始终纳入鉴别诊断，我们应常规应用相关标志物并结合了解患者背景。病例积累对于为这种罕见且侵袭性的恶性肿瘤建立有效的治疗策略不可或缺。
