肝炎性假瘤样滤泡树突状细胞肉瘤2例临床病理观察

Inflammatory pseudotumor-like follicular dendritic cell sarcomas in liver: a clinicopathologic analysis of two cases

目的探讨肝炎性假瘤样滤泡树突状细胞肉瘤(FDCS)的临床病理学特征,提高对该肿瘤的诊断水平。方法对2例肝炎性假瘤样滤泡树突状细胞肉瘤的临床资料、组织学形态、免疫组化、原位杂交进行分析,并复习相关文献。结果肿瘤细胞呈结节状排列,炎细胞背景中散在分布多少不等的肿瘤细胞,瘤细胞胞质丰富,呈淡嗜酸性,胞核圆形、卵圆形或梭形,核染色空淡,可见细小的核仁,常见多核或单核瘤巨细胞,病理性核分裂多见。瘤细胞EBER(+)。免疫组化:CD21、CD35和D2-40(+)。结论肝炎性假瘤样滤泡树突状细胞肉瘤是一种罕见的恶性肿瘤,恶性程度和预后具有不确定性。明确诊断需要结合形态学特点、免疫组化及EBER原位杂交等检查,同时要与肝炎性肌纤维母细胞肿瘤、霍奇金淋巴瘤、指突状树突细胞肉瘤、胃肠间质瘤、特别是炎性假瘤相鉴别。

Objective To explore the clinicopathologic features of inflammatory pseudotumor-like follicular dendritic cell sarcomas(IPT-like FDCS)in liver with discussion on its diagnostic clues.Methods Clinical,histological,immunohistochemical examinations and EBER in situ hybridization were used to investigate the pathological features of 2 cases of IPT-like FDCS,and related literature was reviewed.Results The tumor formed nodosity in patterns and was composed of variable amounts of round to ovoid cells with intense lymphoplasmacytic infiltrate.The nuclei were round,ovoid to spindled in shape with vescular or stippled chromatin and small distinct nucleoli.Scattered multinuclear or mononuclear giant cell and karyokinesis were seen.The tumor cells were immunoreative for CD21,CD35 and D2-40.EBV-encoded small RNA was positive in two cases by in situ hybridization.Conclusions IPT-like FDCS in liver is a rare malignant tumor with uncertain biological behavior and prognosis.Histologic morphology,EBER in situ hybridization and FDCS markers are indispensable for confirming the diagnosis.The tumour should be differentiated from inflammatory myofibroblastic tumour,Hodgkin lymphoma,interdigitating dendritic cell sarcoma,and gastrointestinal stromal tumour,especially inflammatory pseudotumour.