Objective: To study the clinicopathological characteristics, and further understand primary central nervous system T-cell lymphoma (PCNSTCL) in children and adolescents. Methods: Five cases of PCNSTCL in children and adolescents were collected from December 2016 to December 2021 at the First Affiliated Hospital of Zhengzhou University. The clinicopathological characteristics, immunophenotypic, and molecular pathologic features were analyzed, and relevant literatures reviewed. Results: There were two male and three female patients with a median age of 14 years (range 11 to 18 years). There were two peripheral T-cell lymphomas, not otherwise specified, two anaplastic large cell lymphoma, ALK-positive and one NK/T cell lymphoma. Pathologically, the tumor cells showed a variable histomorphologic spectrum, including small, medium and large cells with diffuse growth pattern and perivascular accentuation. Immunohistochemistry and in situ hybridization showed CD3 expression in four cases, and CD3 was lost in one case. CD5 expression was lost in four cases and retained in one case. ALK and CD30 were expressed in two cases. One tumor expressed CD56 and Epstein-Barr virus-encoded RNA. All cases showed a cytotoxic phenotype with expression of TIA1 and granzyme B. Three cases had a high Ki-67 index (>50%). T-cell receptor (TCR) gene rearrangement was clonal in two cases. Conclusions: PCNSTCL is rare, especially in children and adolescents. The morphology of PCNSTCL is diverse. Immunohistochemistry and TCR gene rearrangement play important roles in the diagnosis.
目的： 探讨儿童及青少年原发性中枢神经系统T细胞淋巴瘤（PCNSTCL）的临床病理特征，以提高对本病的认识。 方法： 收集郑州大学第一附属医院2016年12月至2021年12月数据库里确诊的儿童及青少年PCNSTCL病例5例，对其临床特征、病理学特征、免疫表型及分子病理学特征进行观察，并复习相关文献。 结果： 5例患者中，男性2例，女性3例，年龄范围在11~18岁，中位年龄14岁。2例诊断为非特指型外周T细胞淋巴瘤，2例诊断为间变性淋巴瘤激酶（ALK）阳性的间变性大细胞淋巴瘤，1例诊断为NK/T细胞淋巴瘤。病理学特征：肿瘤细胞弥漫性生长，组织学形态谱系较广，可以是小、中、大的细胞，局部可见肿瘤细胞围绕血管壁生长。免疫组织化学及原位杂交：4例表达CD3，1例表达缺失；4例CD5表达缺失，1例未缺失；2例同时表达ALK及CD30；1例表达CD56及EB病毒编码的RNA阳性；5例均表达细胞毒性标志物T细胞胞质内抗原1及颗粒酶B；3例Ki-67阳性指数>50%。2例进行T细胞受体（TCR）基因重排检测，显示单克隆性增生。 结论： PCNSTCL较为少见，发生于儿童及青少年的病例更为罕见，其形态学较多样，免疫组织化学及TCR重排在诊断中起重要作用。.