胃肠道淋巴瘤与间质瘤的CT诊断与误诊分析

CT Features and Misdiagnosis Analysis of Gastrointestinal Stromal Tumor and Gastrointestinal Lymphoma

目的探讨胃肠道淋巴瘤与间质瘤的CT表现,并进一步对误诊病例进行分析。资料与方法搜集经手术及病理证实的15例胃肠道间质瘤和11例胃肠道淋巴瘤患者的CT资料进行回顾性分析。结果15例间质瘤的主要CT特点:(1)巨大不规则肿块,边界清楚,密度不均匀,出血坏死多见(15/15);(2)8例病灶内可见气液平面,3例误诊为淋巴瘤,表现为"假肠腔征",不与周围肠管直接相通(2例),周围可见受压的肠管(1例);(3)肿瘤明显强化,2例CTA显示粗大供血动脉和瘤体内迂曲杂乱肿瘤血管。11例淋巴瘤(包括2例误诊为间质瘤)的主要CT特点:(1)肠管壁广泛增厚,边界清楚,内部积气积液形成"真肠腔征",可见与邻近正常肠管直接相通;(2)肿瘤实质部分密度较均匀,中度强化;(3)肿瘤近端肠系膜淋巴结肿大5例。结论真假肠腔难辨是胃肠道淋巴瘤与间质瘤误诊的主要原因,因此需要积累经验提高对两种疾病的认识。

Objective To compare the CT features of gastrointestinal stromal tumor（GIST） and gastrointestinal lymphoma,then to analysis the misdiagnosis cases.Materials and Methods The CT images of 15 cases with GIST and 11 cases with gastrointestinal lymphoma confirmed by surgery and pathology were retrospectively analyzed.Results The CT features of GIST were as follows：（1）large irregular mass with clear border and inhomogenous density because of necrosis and bleeding;（2）8 cases manifested gas-liquid level,and 3 cases misdiagnosed as lymphoma because of ＂false-intestinal sign＂,in which,the ＂false-intestinal sign＂showed separated from the adjacent intestatinal tract in 2 cases and pressed adjacent intestinaltract in1 case;（3）the tumors had a remarkable and inhomogeneous enhancement in 2 cases,which was confirmed by CTA as abnormal blood-supply artery and tangled tumor vessels.The CT features of gastrointestinal lymphoma included：（1） Greatly thick walls of the involved intestinal tracts with a well-defined margin,called the ＂real-intestinal sign＂,which was found communicated directly with the adjacent intestinal tract;（2） the parenchyma of tumor appeared as uniform density and moderate enhancement;（3） 5 cases showed the large lymph nodes in the proximal mesenteric area.Conclusion In our study,failed to distinguish the ＂real or false intestinal sign＂ was the main reason for misdiagnosis of GIST and gastrointestinal lymphoma,especially when the tumor originated from the small intestine.