Emile J F, Boulland M L, Haioun C, Kanavaros P, Petrella T, Delfau-Larue M H, Bensussan A, Farcet J P, Gaulard P
Département de Pathologie, Hôpital Henri Mondor, Créteil, France.
Blood. 1996 Feb 15;87(4):1466-73.
Non-Hodgkin's lymphomas are divided into B- and T-cell neoplasms. The existence and the clinical relevance of lymphomas derived from the third lymphocyte lineage, ie, natural killer (NK) cells are still controversial. NK cells are lymphocytes that mediate cytotoxicity without prior sensitization. NK cells also have phenotypic and genotypic characteristics: they express the NK-related antigen CD56, T-cell markers such as CD2 and CD7, but do not express CD5 and T-cell receptor (TCR) proteins, and their TCR locus is not rearranged. Therefore, if NK cell lymphomas exist, they should express some T-cell markers, but not alpha beta or gamma delta TCR proteins. Such lymphomas are actually called TCR silent peripheral T cell lymphomas (PTCL). To detect and characterize NK cell lymphomas, we investigated the immunophenotype and immunogenotype of 35 patients with TCR silent PTCL. The first group included 16 patients with a lymphoma of CD5-CD56+ phenotype, which is identical to normal NK cells. These patients had either a nasal/nasopharyngeal lymphoma (11 cases) or a lymphoma with predominant non-nasal/non-nodal initial involvement (five cases). Eight of the nine cases for which immunogenotypic data were available lacked clonal rearrangement of the TCR gamma genes. Thus, these tumors are likely to be NK cell lymphomas. The second group of 15 cases had a CD5+ phenotype (14 were CD56-, and 1 was CD56+) and clonal rearrangement of TCR gamma genes, indicating that they were true PTCL with unproductive TCR rearrangement. The four remaining cases were CD5- CD56- lymphomas and disclosed either a clonal (two cases) or no clonal (two cases) rearrangements of the TCR gamma genes. Altogether these findings show that CD5-CD56+ so-called "TCR silent PTCL" bear the immunophenotype and immunogenotype of normal NK cells and display peculiar clinical features distinct from true PTCL.
非霍奇金淋巴瘤分为B细胞和T细胞肿瘤。源自第三淋巴细胞谱系即自然杀伤（NK）细胞的淋巴瘤的存在及其临床相关性仍存在争议。NK细胞是无需预先致敏即可介导细胞毒性的淋巴细胞。NK细胞也具有表型和基因型特征：它们表达NK相关抗原CD56、T细胞标志物如CD2和CD7，但不表达CD5和T细胞受体（TCR）蛋白，并且它们的TCR基因座未重排。因此，如果NK细胞淋巴瘤存在，它们应该表达一些T细胞标志物，但不表达αβ或γδTCR蛋白。这种淋巴瘤实际上被称为TCR沉默外周T细胞淋巴瘤（PTCL）。为了检测和表征NK细胞淋巴瘤，我们研究了35例TCR沉默PTCL患者的免疫表型和免疫基因型。第一组包括16例CD5-CD56+表型淋巴瘤患者，这与正常NK细胞相同。这些患者患有鼻/鼻咽淋巴瘤（11例）或主要为非鼻/非淋巴结初始受累的淋巴瘤（5例）。在可获得免疫基因型数据的9例病例中，有8例缺乏TCRγ基因的克隆重排。因此，这些肿瘤可能是NK细胞淋巴瘤。第二组15例患者具有CD5+表型（14例为CD56-，1例为CD56+）且TCRγ基因发生克隆重排，表明它们是具有无效TCR重排的真正PTCL。其余4例为CD5-CD56-淋巴瘤，TCRγ基因显示克隆重排（2例）或无克隆重排（2例）。总之，这些发现表明，CD5-CD56+所谓的“TCR沉默PTCL”具有正常NK细胞的免疫表型和免疫基因型，并表现出与真正PTCL不同的特殊临床特征。
