腹内胃肠道外间质瘤的多层螺旋CT表现

Multislice spiral CT features of abdominal extragastrointestinal stromal tumor

目的探讨腹内胃肠道外间质瘤(EGIST)的多层螺旋CT表现,以提高对该肿瘤的CT诊断水平。方法回顾性分析经手术及病理证实的9例腹内EGIST患者的多层螺旋CT表现及临床资料。结果 9例EGIST中,高度危险性6例,中度危险性3例,均为单发,其中肝脏转移1例,1例腹膜及肠系膜种植转移、腹腔淋巴结转移、少量腹腔积液。1例位于十二指肠降部周围,2例位于肠系膜根部,2例位于左下腹小肠系膜周围,1例发生于大网膜,1例位于盆腔右侧,2例位于腹膜后间隙。肿块最大径11~36 cm不等,平均(15±4)cm。椭圆形2例;分叶状、不规则7例,边缘均清晰。9例密度不均,内可见程度不等的坏死、囊变区,其中3例伴有钙化,1例伴有出血。增强扫描肿块实性部分中等至明显不均匀强化,动脉期增强幅度为22~32 Hu,静脉期增强幅度为27~43 Hu,坏死、囊变区无强化,肿块内均未见液气面。5例肿块实质见迂曲条状、簇状的肿瘤血管,经最大密度投影(MIP)成像可见肿瘤血管来源。结论腹内EGIST的MSCT表现有一定的特征性,MSCT有助于判断病变的部位及与周围组织结构的关系,为病变诊断和治疗方案提供重要依据,但确诊有赖于病理及免疫组织化学证实。

Objective To study Multislice spiral CT(MSCT) features of abdominal extragastrointestinal stromal tumor(EGIST) for improving the MSCT diagnosis level. Methods MSCT images and clinical data of 9 patients with pathologically confirmed EGIST were reviewed retrospectively. Results There were 9 cases with single mass.Of the 6 high-risk EGISTs and 3 intermediate-risk EGISTs,metastasis was observed in the liver(1 case), abdominal cavity,mesentery,abdominal lymphonodi and a small amount of ascites(1 cases),around the descending duodenum(1 case),mesentery root(2 cases),left lower abdominal mesentery(2 cases),great omentum(1 case),right pelvis(1 case),or retroperitoneal space(2 cases).The mean tumor size was(15±4)cm(11~36 cm). The tumor was round(2 cases) or irregular(7 cases) with well-defined boundary.Unenhanced CT showed heterogeneous density with cystic-necrotic components in all 9 masses with calcification(3 cases) or hemorrhage(1 case).The solid components showed moderate to obvious enhancement with CT values of 22~32 Hu in the arterial phase and 27-43 Hu in the venous phase,and the cystic-necrotic components did not enhance.These tumors were free liquid-gas surface. Maximum intensity projection(MIP) helped to clarify tumor blood supply in 5 tumors with stripe-like and clustered vessels. Conclusion The MSCT findings of EGIST were relatively characteristic. MSCT imaging can clearly display tumor location and relationship with adjacent structures, and provide important evidence for clinical diagnosis and treatment protocols.Ultimate diagnosis depends on pathology and immunohistochemistry.