巨细胞纤维母细胞瘤的临床与病理学观察

目的：研究巨细胞纤维母细胞瘤的临床病理学特点和免疫组织化学表型,探讨其鉴别诊断及组织学起源。方法：采用光镜观察结合免疫组织化学LSAB法标记对7例巨细胞纤维母细胞瘤进行分析。结果：7例患者中6例为儿童,1例为35岁成年人。男性5例,女性2例。临床上主要表现为躯干和四肢皮下缓慢增大的无痛性结节,平均直径2．9cm。镜下显示,肿瘤境界不清,主要位于真皮层。瘤细胞主要由轻至中度异型的梭形细胞组成,多呈疏松的束状或波浪状排列,间质呈纤维黏液样,部分区域呈致密胶原化。本病的特征性形态表现肿瘤内含有一些不规则分布的裂隙样或扩张窦样的假脉管性腔隙,其腔隙面内衬一层不连续的梭形细胞和核深染多核巨细胞,两种细胞在形态上有移行。免疫组织化学标记显示梭形细胞和多核巨细胞均表达波形蛋白和CD34.5 附有随访资料,其中2例术后复发。结论：（1）巨细胞纤维母细胞瘤是一种好发于儿童的中间性纤维母细胞性肿瘤,较易局部复发,掌握其独特的临床病理学特征对避免误诊为一些具有相似形态的病变具有重要意义;（2）巨细胞纤维母细胞瘤与好发于成人的隆突性皮纤维肉瘤的在临床表现、免疫组织化学、细胞及分子遗传学上均极为相似,在组织上也可共存,提示两者在组织学发生了关系密切,可能同属CD34阳性树突状纤维母细胞肿瘤一族。

Giant cell fibroblastoma: a clinicopathologic analysis of seven cases

Objective To study the clinical, pathological and immunohistochemical features of giant cell fibroblastoma (GCF), with emphasis on its differential diagnosis and histogenesis. Methods Seven cases of GCF were investigated by light microscopy and immunohistochemistry. Results Six cases occurred in children, and one occurred in a 35 year old adult (mean 9.4 years). Five were male and two were female. Clinically, all cases appeared as slowly growing painless nodules located in the dermis or subcutis of the trunk and extremities. Microscopically, the poorly circumscribed tumor was composed of a proliferation of slightly to moderately atypical spindle cells which were arranged in parallel or wavy fascicles, and embedded in a fibromyxoid to collagenous background. The pathognomonic feature consisted of irregular distributed cleft like or sinusoid like pseudovascular spaces lined with a discontinuous layer of pleomorphic spindle cells and multinucleate giant cells. There was transition in shape between these two cells. Immunohistochemially, both cells expressed vimentin and CD34. Follow up information in five cases showed local recurrences in two cases. Conclusions (1) GCF is a distinctive fibroblastic tumor of intermediate malignancy that occurs predominantly in children. Recognizing its clinical and pathological characteristics is important to avoid misdiagnosis with other lesions with similar features. (2) GCF shared clinical, immunohistochemical and cytogenetic features with its adult counterpart dermatofibrosarcoma protuberans (DFSP). The additional coexistence of GCF and DFSP areas in some primary cases and the reciprocal transformation in recurrent tumors all suggest that they are two closely related entities, possibly representing two members of the CD34 positive dendritic neoplasms.