结外NK/T细胞淋巴瘤伴B淋巴细胞增生2例的临床病理学研究

Clinicopathological Study of Two Cases of Extranodal NK/T-cell Lymphoma with B-Lymphocytosis

目的探讨结外NK/T细胞淋巴瘤(extranodal NK/T cell lymphoma,ENKTL)伴B淋巴细胞增生病例的临床病理学特征。方法收集陕西省人民医院2023年6~9月确诊的2例ENKTL伴B淋巴细胞增生病例,采用HE染色、免疫组织化学和原位杂交EB病毒编码的小RNA(Epstein-barr virus encoded small RNA,EBER)检测,观察其组织学特征、免疫表型及原位杂交EBER检测结果,并进行相关文献复习。结果2例老年男性患者,病变部位均为右侧鼻腔,组织学特征为肿瘤细胞弥漫分布,细胞大中小不等,以中大细胞为主,胞核不规则,胞质淡染或透明,核椭圆形,染色质呈颗粒状,核仁不明显,核分裂象较多见,凝固性坏死及凋亡明显;背景见小淋巴细胞灶状聚集,淋巴滤泡散在分布。免疫组织化学CD2,CD3,CD56,TIA-1和颗粒酶B(GrB)阳性表达;CD20,CD79a和PAX-5局灶阳性表达;CD21,CD23及CD35见残存FDC网;CD5阴性表达;Ki-67增殖指数约30%。原位杂交检测EBER肿瘤细胞阳性。病理诊断:ENKTL伴B淋巴细胞增生。结论结外NK/T细胞淋巴瘤伴B淋巴细胞增生少见,尤其是B淋巴细胞增生形成淋巴滤泡时,经验不足很容易造成诊断困扰,需结合临床表现、组织学形态、免疫表型综合分析和诊断。

Objective To investigate the clinicopathological characteristics of extranodal NK/T cell lymphoma(ENKTL)with B-lymphocytosis.Methods Two cases of ENKTL with B-lymphocytosis diagnosed in Shaanxi Provincial People’s Hospital from June to September 2023 were collected.HE staining,immunohistochemistry,and in situ hybridisation Epsteinbarr virus encoded small RNA(EBER)testing was used to observe the histological features,immunophenotypes,and results of the in situ hybridisation EBER testing.A review of the relevant literature was conducted.Results In two cases of elderly male patients,whose lesion sites were on both the right side of the nasal cavity,histological characteristics of the tumor cells were diffuse distribution.The cells were of different sizes,mainly medium and large cells,with irregular nuclei,stained or transparent cytoplasm,oval nuclei,granular chromatin and inconspicuous nucleoli.Nuclear schizophrenia was more common and coagulative necrosis and apoptosis were evident.Foci of small lymphocyte aggregates were seen in the background and lymphoid follicles were distributed in a scattered manner.Immunohistochemical CD2,CD3,CD56,TIA-1 and granzyme B(GrB)were positive.CD20,CD79a and PAX-5 were focal positive.CD21,CD23 and CD35 had residual FDC network,and CD5 was negative.Ki-67 proliferation index was approximately 30%.EBER tumor cells detected by in situ hybridisation were positive.Pathological diagnosis showed ENKTL with B-lymphocytosis.Conclusion NKTL with B-lymphocytosis was rare,especially when B-lymphocyte hyperplasia formed lymphoid follicles.Lack of experience can easily cause diagnostic difficulties,and comprehensive analysis and diagnosis should be combined with the clinical manifestations,histological morphology and immunophenotype.