十二指肠炎性纤维性息肉1例并文献复习

Inflammatory fibroid polyp of duodenum: report of a case and review of literature

目的 探讨罕见发生于十二指肠的炎性纤维性息肉(inflammatory fibroid polyp, IFP)的临床病理特点。方法 回顾性分析1例十二指肠IFP的临床特征、病理学形态、免疫组织化学及分子检测结果,并复习国内外相关文献。结果 本例患者女性,57岁,腹胀4年,偶有腹痛、腹泻,CT示十二指肠突向腔内肿物,胃镜显示十二指肠息肉样隆起性肿物,镜下可见肿物位于黏膜下层,肿瘤细胞短梭形,均匀分布于疏松水肿、黏液样间质中,间质可见丰富小血管及嗜酸性粒细胞浸润,免疫组化结果显示肿瘤细胞CD34、血小板衍生生长因子受体α(PDGFRA)、Vimentin阳性,SMA、SMMS-1、Desmin、ALK、DOG-1、CD117、S-100、EMA、Fli-1、CD68、β-catenin和CKpan均呈阴性表达,Ki-67增殖指数1%。分子检测结果示KIT基因无突变,PDGFRA基因18外显子突变。患者行超声内镜下肿物切除术,术后随访4个月无复发。结论 十二指肠IFP是一种罕见的胃肠道良性间叶源性肿瘤,病理形态及免疫表型无特异性,分子检测可见PDGFRA基因突变,正确认识本病十分重要,可以为临床选择合适的手术方式提供帮助。

Objective To investigate the clinicopathological features of inflammatory fibrous polyp(IFP) in the duodenum. Methods The pathological feature, immunophenotype and molecular changes of a duodenal IFP were retrospectively analyzed and the relevant literature was reviewed. Results A 57-year-old female patient presented with abdominal distension for four years, who had occasional abdominal pain and diarrhea. CT showed a duodenal mass protruding into the cavity. Gastroscopy showed a polypoid mass located under the mucosa. Tumor cells were short spindled in shape and evenly distributed in the myxoid stroma. Abundant small blood vessels and a small amount of eosinophils were seen in the stroma. Immunohistochemical staining showed that CD34, PDGFRA and vimentin were positive in the tumour cells, but SMA, SMMS-1, desmin, ALK, DOG-1 CD117, S-100, EMA, Fli-1, CD68, β-catenin and Ckpan were negative;Ki-67 index was 1%. No KIT gene mutation was found, but exon 18 mutation of PDGFRA gene was confirmed. The patient underwent endoscopic ultrasound guided tumor resection and was followed up for 4 months without recurrence. Conclusion Duodenal IFP is a rare benign tumor of the gastrointestinal tract. There is no specific features in pathological morphology and immunophenotype, but PDGFRA gene mutation can be detected. It is important to have a correct understanding of this disease, which is helpful to choose the appropriate surgical modality.