术前应用超声内镜与三期增强CT诊断胃肠道间质瘤的临床价值

Clinical value of preoperative endoscopic ultrasonography and phase Ⅲ enhanced CT in the diagnosis of gastrointestinal stromal tumor

目的 研究胃肠道间质瘤(GIST)患者术前诊断中超声内镜与三期增强电子计算机断层扫描(CT)的应用价值。方法 采用回顾性分析方法,以2017年1月至2021年6月入山西省运城市中心医院的100例GIST患者为观察对象,所有患者均接受超声内镜与三期增强CT检查,比较两种检查方式的定位诊断正确率、定性诊断正确率,并分析胃肠道间质瘤的超声内镜、三期增强CT影像学特征。结果 (1)肿瘤基本情况。肿瘤部位:1例直肠,2例结肠,1例食管,7例十二指肠,12例小肠,77例胃部。59例肿块形态不规则,边界不清,其中30例与邻近脏器粘连;41例肿块形态规则,边界清晰。(2)定位、定性诊断正确率。以病理组织学结果为诊断金标准,GIST诊断中超声内镜检查的定位诊断正确率为95.00%,定性诊断正确率为87.00%;三期增强CT检查的定位诊断正确率为80.00%,定性诊断正确率为53.00%;超声内镜检查的定位诊断正确率、定性诊断正确率均明显高于三期增强CT检查,差异有统计学意义(P<0.05)。(3)影像学特征。超声内镜:可见椭圆形或者类圆形隆起,表面黏膜呈光滑状态,触感硬质,少数病变存在于顶部且可见溃疡,隆起来自固有肌层的胃黏膜下肿瘤,源于超声第四层,边界清晰,低回声,超声第五层结构完整且清晰。三期增强CT:CT平扫可见圆形或者类圆形肿块影,呈分叶状且不规则,肿块呈软组织密度,肿瘤内可见多个或者单个小片状低密度坏死灶与结节状钙化;CT增强扫描可见肿瘤重度至显著强化,其中59例延迟性强化,41例持续性强化。22例增强后延迟期、静脉期、动脉期呈不同程度显著强化,肿块部分液化及坏死;23例呈结节状钙化,增强后肿块轻度及中度强化;25例显著强化,肿块中间坏死,可见气液平面;30例呈囊实性,见条状分隔影,囊性未出现强化表现,条状分隔与实性部分呈不均匀延迟或持续强化与片絮状。结论 GIST患者术前诊断中超声内镜的定位、定性诊断准确率均高于三期增强CT,可有效提升诊断准确性;但三期增强CT对GIST病变坏死情况(病变邻近结构及脏器侵犯、远处转移)的显示更加清晰,临床诊断可考虑联合两种检查方式以进一步提升定位、定性诊断准确性。

Objective To study the application value of ultrasound endoscopy and enhanced computed tomography(CT) in preoperative diagnosis of gastrointestinal stromal tumor(GIST). Methods A retrospective analysis method was used to take 100 GIST patients admitted to Yuncheng Central Hospital of Shanxi Province from January 2017 to June 2021 as the observation objects. All patients received ultrasound endoscopy and three-phase enhanced CT examinations, and the localization diagnosis of the two examination methods was compared. Correct rate, qualitative diagnosis rate, and analysis of ultrasound endoscopy and three-phase enhanced CT imaging features of gastrointestinal stromal tumors.Results(1)Basic information of tumor. Tumor sites: 1 rectum, 2 colon, 1 esophagus, 7 duodenum, 12 small intestine, and 77 stomach. Fifty-nine cases had irregular shape and unclear boundary, of which 30 cases adhered to adjacent organs. 41 cases had regular shape and clear boundary.(2)Accurate rate of localization and qualitative diagnosis. In GIST diagnosis, the accuracy of ultrasound endoscopy examination was 95.00%, and the accuracy of qualitative diagnosis was 87.00%. The accuracy of ultrasound endoscopy examination was 80.00%, and the accuracy of qualitative diagnosis was 53.00%. The accuracy of localization and qualitative diagnosis in ultrasound endoscopy was significantly higher than that in three-phase enhanced CT(P<0.05).(3)Imaging features. Ultrasound endoscopy: oval or circular eminence can be seen, the surface mucosa is smooth and hard to touch, a few lesions exist at the top and ulcer can be seen, the eminence is from gastric submucosal tumor of muscularis propria, which is derived from the fourth ultrasound layer, with clear boundary and low echo, and the fifth ultrasound layer has complete and clear structure. Phase Ⅲ enhanced CT: plain CT showed round or quasi-round mass, lobulated and irregular, with soft tissue density, multiple or single small patchy low-density necrotic foci and nodular calcification in the tumor. Contrast-enhanced CT showed severe to significant enhancement of tumors, including delayed enhancement in 59 cases and persistent enhancement in 41 cases. After enhancement, 22 patients showed different degrees of significant enhancement in the delayed, venous and arterial phases, with partial liquefaction and necrosis of the mass. Twenty-three cases showed nodular calcification with mild and moderate enhancement after enhancement. In 25 cases, there was significant enhancement and necrosis in the middle of the mass, with gas-liquid plane visible. Thirty cases presented cystic solid, strip separation shadow, no enhancement of cystic, strip separation and solid part showed uneven delayed or continuous enhancement and flocc. Conclusion The positioning and qualitative diagnostic accuracy of ultrasound endoscopy in preoperative diagnosis of GIST patients is higher than that of phase Ⅲ enhanced CT, which can effectively improve the diagnostic accuracy. However, phase Ⅲ enhanced CT can show more clearly the necrosis of GIST lesions(adjacent structures, invasion of organs and distant metastasis). Clinical diagnosis can consider the combination of the two examination methods to further improve the accuracy of positioning and qualitative diagnosis.