腹腔滤泡树突状细胞肉瘤1例并文献复习

Follicular dendritic cell sarcoma of the abdominal cavity:a case report and literature review

目的探讨淋巴结外滤泡树突状细胞肉瘤(follicular dendritic cell sarcoma,FDCS)的临床病理特征、鉴别诊断、治疗及预后,提高诊断水平。方法回顾性分析1例腹腔FDCS的临床病理特征、免疫表型及遗传学特征,并复习相关文献。结果HE染色检测示肿瘤由梭形细胞构成,肿瘤细胞呈束状、席纹状及弥漫片状分布,伴大量小淋巴细胞浸润,可见血管淋巴套;肿瘤细胞胞质中等,核大呈空泡状,可见核仁及核内假包涵体,核分裂像罕见,可见多核瘤巨细胞,间质纤维组织增生伴胶原沉积,未见坏死,肿瘤可见纤维性包膜,局部呈浸润性生长。免疫组织化学检测示CD21、CD23、CD35、D2-40、EMA、vimentin、SMA阳性,S-100、desmin、CD34、CD117、ALK、CK、STAT6、MDM2阴性,Ki-67增殖指数约15%。EBER原位杂交和克隆性基因重排检测结果均为阴性。患者术后化疗6周期,一般状况良好,未见复发和转移。结论发生于结外(腹腔内)的FDCS非常少见,其组织学形态具有多样性,常伴有小淋巴细胞浸润和独特的免疫表型。提高对结外部位FDCS的认识可能有助于减少诊断错误。

Objective To explore the clinicopathologic features,differential diagnosis,treatment and prognosis of extranodal follicular dendritic cell sarcoma(FDCS)to improve the diagnostic capability.Methods The clinicopathological features,immunophe-notype and genetic features of a case of abdominal FDCS were retrospectively analyzed,and related literature was reviewed.Results HE staining showed the neoplasm consists of spindled cells forming fascicles,storiform arrays and diffuse sheets;the tumor was heavily infiltrated by small lymphocytes,which could be aggregated around the blood vessels as well;the neoplastic cells generally showed a moderate amount of eosinophilic cytoplasm;the nuclei were large,with vesicular chromatin,small but distinct nucleoli;nuclear pseudoinclusions were common;atypical mitoses were rare;multinucleated tumor cells were seen;the tumor stroma showed fibrous tissue proliferation with collagen deposition,but no obvious necrosis;the tumor had a fibrous envelope and was infiltrating growth.Immunohistochemical examination showed that CD21,CD23,CD35,D2-40,EMA,vimentin,SMA were positive,but S-100,desmin,CD34,CD117,ALK,CK,STAT6,MDM2 were negative,and the proliferation index of Ki-67 was 15%.The results of EBER in situ hybridization and clonal gene rearrangement were negative.The patient received 6 cycles of chemotherapy after operation,and was generally in good condition without recurrence and metastasis.Conclusion Extranodal(intraperitoneal)FDCS is very rare and has diverse histological features,often presenting with small lymphocytic infiltrates and a distinct immunophenotype.Increasing the awareness of extranodal FDCS may help reduce diagnostic errors.