Abstract：
BACKGROUND: Follicular dendritic cell sarcoma is a rare stromal tumor with no standard treatment. However, some reports have revealed that follicular dendritic cell sarcoma has an inflammatory pseudotumor variant associated with Epstein-Barr virus infection that has a relatively good prognosis. In this report, we present a case of a resected inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver, and have reviewed the literature on the clinicopathological, molecular, and genomic features of this tumor.
METHODS: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma originates only in the liver or spleen, causes no symptoms, and is more common in middle-aged Asian women. It has no characteristic imaging features, which partially explains why the inflammatory pseudotumor variant of follicular dendritic cell sarcoma is difficult to diagnose. Pathologically, the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has spindle cells mixed with inflammatory cells and is variably positive for follicular dendritic cell markers (CD21, CD23, and CD35) and Epstein-Barr virus-encoded RNA. On genetic analysis, patients with this tumor high levels of latent membrane protein 1 gene expression and extremely low levels of host C-X-C Chemokine Receptor type 7 gene expression, indicating that the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has a latent Epstein-Barr virus type 2 infection.
CONCLUSIONS: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma is an Epstein-Barr virus-associated tumor and a favorable prognosis by surgical resection, similar to Epstein-Barr virus-associated gastric cancer.
METHODS: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma originates only in the liver or spleen, causes no symptoms, and is more common in middle-aged Asian women. It has no characteristic imaging features, which partially explains why the inflammatory pseudotumor variant of follicular dendritic cell sarcoma is difficult to diagnose. Pathologically, the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has spindle cells mixed with inflammatory cells and is variably positive for follicular dendritic cell markers (CD21, CD23, and CD35) and Epstein-Barr virus-encoded RNA. On genetic analysis, patients with this tumor high levels of latent membrane protein 1 gene expression and extremely low levels of host C-X-C Chemokine Receptor type 7 gene expression, indicating that the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has a latent Epstein-Barr virus type 2 infection.
CONCLUSIONS: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma is an Epstein-Barr virus-associated tumor and a favorable prognosis by surgical resection, similar to Epstein-Barr virus-associated gastric cancer.
摘要：
背景：滤泡树突状细胞肉瘤是一种罕见的无标准治疗的间质瘤。然而,一些报道显示,滤泡树突状细胞肉瘤具有与EB病毒感染相关的炎性假瘤变异体,预后相对良好.在这份报告中,我们介绍了一例肝脏滤泡树突状细胞肉瘤的炎性假瘤变异体，并回顾了有关临床病理的文献，分子，和这个肿瘤的基因组特征。
方法：滤泡树突状细胞肉瘤的炎性假瘤变体仅起源于肝脏或脾脏，没有症状，在亚洲中年女性中更为常见。它没有特征性的成像特征，这部分解释了为什么滤泡树突状细胞肉瘤的炎性假瘤变体难以诊断。病理上,滤泡树突状细胞肉瘤的炎性假瘤变异体具有梭形细胞与炎性细胞混合,滤泡树突状细胞标志物(CD21,CD23和CD35)和EB病毒编码的RNA呈可变阳性.在遗传分析中,这种肿瘤患者的潜伏膜蛋白1基因表达水平高，宿主C-X-C趋化因子受体7型基因表达水平极低，表明滤泡树突状细胞肉瘤的炎性假瘤变体具有潜伏的EB病毒2型感染。
结论：滤泡树突状细胞肉瘤的炎性假瘤变种是一种EB病毒相关肿瘤，手术切除预后良好，与EB病毒相关的胃癌相似。
方法：滤泡树突状细胞肉瘤的炎性假瘤变体仅起源于肝脏或脾脏，没有症状，在亚洲中年女性中更为常见。它没有特征性的成像特征，这部分解释了为什么滤泡树突状细胞肉瘤的炎性假瘤变体难以诊断。病理上,滤泡树突状细胞肉瘤的炎性假瘤变异体具有梭形细胞与炎性细胞混合,滤泡树突状细胞标志物(CD21,CD23和CD35)和EB病毒编码的RNA呈可变阳性.在遗传分析中,这种肿瘤患者的潜伏膜蛋白1基因表达水平高，宿主C-X-C趋化因子受体7型基因表达水平极低，表明滤泡树突状细胞肉瘤的炎性假瘤变体具有潜伏的EB病毒2型感染。
结论：滤泡树突状细胞肉瘤的炎性假瘤变种是一种EB病毒相关肿瘤，手术切除预后良好，与EB病毒相关的胃癌相似。
