Yu Wei-Wen, Hsieh Pin-Pen, Chuang Shih-Sung
Department of Dermatology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
J Cutan Pathol. 2013 Mar;40(3):310-6. doi: 10.1111/cup.12066. Epub 2012 Dec 14.
Primary cutaneous γδ T-cell lymphoma and extranodal natural killer (NK)/T-cell lymphoma (ENKTL), nasal type are two distinct lymphoma entities in the World Health Organization (WHO) classification. We report the case of an aggressive cutaneous lymphoma of γδ T-cell origin showing overlapping features of both lymphomas. A 78-year-old female presented with confluent erythematous plaques with ulcerations over her right thigh. Microscopically, section of the skin showed a diffuse dermal and subcutaneous lymphocytic infiltration with tumor necrosis and angioinvasion. The medium- to large-sized tumor cells expressed CD3, CD8, cytotoxic molecules and T-cell receptor (TCR)-γ but not CD4, CD20, CD30, CD56 or βF1. In situ hybridization for Epstein-Barr virus-encoded mRNA (EBER) was diffusely positive. Polymerase chain reaction-based clonality assay showed a clonal TCR-γ chain gene rearrangement. The features compatible with γδ T-cell lymphoma include dermal and subcutaneous involvements, cytotoxic phenotype, expression of TCR-γ, as well as an aggressive course. On the other hand, the diffuse EBER positivity, angioinvasion, tumor necrosis and cytotoxic phenotype may also fit in the diagnosis of an ENKTL of T-cell lineage. We review the literature on EBER-positive γδ T-cell lymphoma and discuss the diagnostic dilemma using the current WHO classification system.
原发性皮肤γδ T细胞淋巴瘤和结外自然杀伤（NK）/T细胞淋巴瘤（ENKTL）鼻型是世界卫生组织（WHO）分类中的两种不同淋巴瘤实体。我们报告了一例起源于γδ T细胞的侵袭性皮肤淋巴瘤病例，其表现出这两种淋巴瘤的重叠特征。一名78岁女性患者右大腿出现融合性红斑伴溃疡。显微镜下，皮肤切片显示真皮和皮下弥漫性淋巴细胞浸润，伴有肿瘤坏死和血管侵犯。中至大型肿瘤细胞表达CD3、CD8、细胞毒性分子和T细胞受体（TCR）-γ，但不表达CD4、CD20、CD30、CD56或βF1。爱泼斯坦-巴尔病毒编码mRNA（EBER）原位杂交呈弥漫性阳性。基于聚合酶链反应的克隆性检测显示克隆性TCR-γ链基因重排。与γδ T细胞淋巴瘤相符的特征包括真皮和皮下受累、细胞毒性表型、TCR-γ表达以及侵袭性病程。另一方面，弥漫性EBER阳性、血管侵犯、肿瘤坏死和细胞毒性表型也可能符合T细胞系ENKTL的诊断。我们回顾了关于EBER阳性γδ T细胞淋巴瘤的文献，并使用当前的WHO分类系统讨论了诊断困境。
