实性型血管瘤样纤维组织细胞瘤临床病理观察

Solid variant of angiomatoid fibrous histocytoma： report of 3 cases

目的 探讨实性型血管瘤样纤维组织细胞瘤的临床病理特点、免疫表型、分子遗传学改变、病理诊断及鉴别诊断要点.方法 收集3例实性型血管瘤样纤维组织细胞瘤,复习相关文献,分析其临床病理学特点.采用免疫组织化学EnVision法检测相关标志物.采用荧光原位杂交方法检测EWSR1基因融合情况.结果 临床特点：3例患者,2例男性,1例女性,年龄9～12岁.临床表现为无痛性肿块,分别位于左前臂、左膝及背部.肿块均完整切除.病理检查：肿瘤最大直径1.6～4.5 cm,境界清楚,切面灰白、灰黄或灰红,质实.镜下观察：瘤细胞呈组织细胞样,实性片状排列,均有较厚的纤维性假包膜及周围淋巴、浆细胞浸润.免疫组织化学：3例均表达波形蛋白、CD68,均不表达S-100蛋白、CK、CD34、CD31、平滑肌肌动蛋白、CD35、CD21、CD30.2例表达CD99,其中1例还同时表达结蛋白、上皮细胞膜抗原.荧光原位杂交检测结果显示EWSR1阳性.结论 实性型血管瘤样纤维组织细胞瘤是血管瘤样纤维组织细胞瘤的一种亚型,属于交界性病变,其诊断主要依靠病理形态学特点,免疫组织化学标记和EWSR1基因检测十分有助于诊断及鉴别诊断.

Objective To study the clinicopathologic features,immunophenotype,molecular genetics and differential diagnosis of solid variant of angiomatoid fibrous histocytoma.Methods The clinicopathologic features of 3 cases of solid variant of angiomatoid fibrous histocytoma were analyzed and the literature was reviewed.Results There were a total of 2 males and 1 female.The age of patients ranged from 9 to 12 years.The patients presented with a painless mass located in left forearm,left knee or back.The lesions were treated by complete surgical resection.On gross examination,the tumors varied from 1.6 cm to 4.5 cm in greatest dimension.They were well-circumscribed and had pale yellow to grayish-red solid cut surface.Histologically,the tumor was composed of histocytoid cells arranged in sheet-like pattern.A fibrous pseudocapsule surrounded by lymphocytes and plasma cells was identified.Immunohistochemical study showed that the tumor cells in all cases were positive for vimentin and CD68.They were negative for S100 protein,cytokeratin,CD34,CD31,smooth muscle actin,CD35,CD21 and CD30.Two cases also expressed CD99 and one of them was positive for desmin and epithelial membrane antigen.Fluorescence in-situ hybridization was positive for EWSR1 gene.Conclusions Solid type represents a variant of angiomatoid fibrous histocytoma and is considered as tumor of borderline malignant potential.Definitive diagnosis requires thorough histologic examination and clinical correlation.Immunohistochemistry and EWSR1 gene study are helpful in further delineation and differential diagnosis.Complete resection or wide local excision with post-operative follow up is the main modality of treatment.