胃肠道间质瘤的CT诊断及不同危险性征象分析

目的分析胃肠道间质瘤的CT特点及不同危险性CT征象。方法分析34例经手术病理证实的胃肠道间质瘤的GT表现，并与手术及病理所见相对照；分析依据病理组织学分级的不同危险性组别的CT征象，并对其差别进行统计分析。结果（1）肿块起源于胃部21例．十二指肠2例，小肠7例，回盲部2例，直肠2例。（2）病理分型：高危17例，中危10例，低危6例，极低危为1例。（3）典型CT表现为不规则形或类圆形软组织肿块，多外向性生长，边界清楚，密度不均，与病理对照为坏死囊变、黏液变性及空洞或窦道形成。增强扫描多明显强化，动静脉期强化峰值无明显变化。（4）胃肠道间质瘤大小（以5cm为界）、形态、密度、强化动脉期有无血管样影，在不同危险性组别（极低及低危险组与中高危险组）中差异有统计学意义（P〈0.05）；强化程度的差别无统计学意义（P〉0.05）。结论胃肠道间质瘤CT表现有一定的特点；不同危险性肿瘤的某些CT征象有差异性，中高危险性多表现为直径大于5cm、密度不均匀、形态不规则、见血管样强化。

Analysis of CT Diagnose and Different Risk Manifestations of Gastrointestinal Stromal Tumors

Objective To investigate the CT features and different manifestations of gastrointestinal stromal tumors. Methods The CT imaging data of 34 cases of gastrointestinal stromal tumor confirmed by pathology and compared with operative and pathologic findings were retrospectively studied. Analyzing the CT features based on Histopathological classification of the different risk groups and using statistics to compare the differences. Results （1） Tumors originated from the stomach in 21 cases, duodenum in 2 cases, small intestine in 7 cases, ileocecal junction in 2 cases and rectum 2 cases.（2）The pathologic of different risk which included high-risk, intermediated-risk, low-risk, and very low-risk were 17cases, 10 cases, 6 cases and 1 cases respectively. （3） A typical CT manifestations were a outward growth of irregular or round soft tissue mass which have clear boundary and the density non-homogeneous, which corresponding to necrosis, cystic change, mucoid degeneration and sinus or cavity. The Enhancement of lesion was obvious and not homogeneous which showed little change in peak of enhancement between arterial phase and venous phase. （4） Gastrointestinal stromal tumors take 5 cm as the boundary which including different size, shape, density, and appearance vessellike artery shadow at arterial phase between different risk groups（low, very low-risk group and intermediated, high-risk group） were statistically different（P〈0.05）, while enhanced degree without significant difference （P〉 0.05）. Conclusion CT findings of gastrointestinal stromal tumors have characteristics, and CT features have significant difference between different risk groups. These features of more than 5 cm in diameter, density nonhomogeneous, irregular shape and, chaos appearance alike vascular enhancement were showed in intermediated-high-risk group.