摘要目的 提高对气管外周原始神经外胚层瘤(PNET)的认识.方法 报道1例2010年7月确诊的气管外周PNET患者的临床资料、诊治经过及随访情况,并进行相关文献复习.以“原始神经外胚层瘤,外周”为检索词通过万方医学数据库对中文文献进行检索,以“primitive neuroeetodermal tumor,peripheral”为检索词通过PubMed数据库进行检索,检索时间截至2011年9月.结果 患者女,63岁,因“咳嗽、咳痰50 d,气促1个月”入院.入院前曾误诊为“慢性咽炎、慢性支气管炎、支气管哮喘”.入院后胸部CT示气管中段占位性病变.支气管镜检查示声门下4 cm处可见带蒂肿物,肿物包膜完整,表面光滑,血管丰富,行支气管镜下气管肿物高频圈套电切电凝术.术后病理报告支气管黏膜下可见片状小圆形恶性肿瘤细胞浸润,免疫组织化学染色CD56及CD99呈弥漫强阳性,突触素及S-100蛋白阳性；白血病融合转录因子-1(FLI-1)融合基因表达阳性；确诊为气管外周PNET.患者术后咳嗽、气促症状消失,随访至今14个月,未见肿瘤局部复发及远处转移.在万方医学数据库上检索到40篇文献共187例PNET,24篇为回顾性分析,16篇为个案报道；在PubMed检索系统检索到111篇文献,1篇为前瞻性研究,1篇为综述,22篇为回顾性分析,87篇为个案报道,但均未见外周气管PNET的报道.结论 气管外周PNET可发生于气管,易误诊,诊断主要依靠组织病理学及免疫组织化学染色,EWS-FLI-1融合基因阳性可作为确诊气管外周PNET的可靠指标；气管外周PNET可能与发生于其他部位的PNET不同,其侵袭性低,远处转移较少.

abstractsObjective To improve the understanding of tracheal peripheral primitive neuroectodermal tumor(PNET).Methods A case of tracheal PNET diagnosed in July 2010 was reported and the related literatures were reviewed.The literature review was carried out respectively with “primitive neuroectodermal tumor”,“peripheral” as the search terms in Wanfang med online and PubMed database by September 2011.Results A case of 63 year-old female patient,who had been misdiagnosed as having chronic pharyngitis,chronic bronchitis and bronchial asthma,was admitted to the hospital because of cough and sputum production for 50 days,and anhelation for 1 month.After admission,the chest computerized tomography showed a space-occupying lesion in the middle of the trachea.Bronchoscopy showed a pedicle neoplasm 4 cm under the subglottic,with integral capsule,smooth surface and rich vascellum.Subsequently,tumor resection under bronchoscope was performed.Pathology report after operation showed infiltration of flake small round malignant cells under bronchial mucosa.Immunohistochemistry showed CD99 (+),Syn (+)and S-100 (+).EWS-FLI-1 fusion transcript was detected by RT-PCR.Accordingly,it was diagnosed as PNET.The symptoms of cough and anhelation were disappeared after operation.So far,there was no local recurrence and distant metastasis with 14 months follow-up.A total of 111 literatures were received in Pubmed,including one of prospective study,one of review,22 of retrospective study and 87 of case report.Forty literatures and 187 cases in all were received in Wanfang Med Online,including 24 of retrospective study and 16 of case report.But,there were no reports about tracheal PNET.Conclusions PNET can occur in the trachea and is easy to be misdiagnosed.To make a definite diagnosis,histopathology and immunohistochemistry are needed and detection of EWS-FLI-1 fusion transcript is a reliable marker for molecular diagnosis.The tracheal pPNET may be different with the pPNETs in other parts,and has a lowergrade invasion and less distant metastasis.