胃神经鞘瘤超声内镜下被误诊为胃间质瘤4例并文献复习*

4 cases of gastric schwannoma misdiagnosed as gastric stromal tumors by endoscopic ultrasonography and literature review*

摘要:

目的   为了提高超声内镜（EUS）对胃神经鞘瘤的检出率。方法   回顾分析2008年5月-2015年6月温州医科大学附属第一、第二医院和台州市第一人民医院4例病理及免疫组化确诊为胃神经鞘瘤但经EUS误诊为胃间质瘤的临床资料及EUS的影像特征并文献复习。结果  4例胃神经鞘瘤均为女性且均为良性，胃镜下4例病灶均为单发，有3例位于胃体，1例位于胃底；EUS下病灶均起源于胃固有肌层，病灶处呈低回声团块，回声均匀，边界清楚，内部回声均未见钙化灶或囊性变；2例病灶周围可见光晕现象。文献复习发现：胃神经鞘瘤好发于女性；周围光晕现象可能为胃神经鞘瘤的特征性表现；钙化、囊性液化改变在胃神经鞘瘤中较少见，在胃间质瘤中较常见。结论   位于固有肌层的胃神经鞘瘤与胃间质瘤在EUS下很难区分；对病灶位于胃体、超声图像示病灶起源于固有肌层，呈低回声、回声均匀、边界清楚的女性患者，需仔细观察病灶内部回声是否有钙化、囊性变以及病灶周围是否有光晕现象，综合考虑，除需考虑胃间质瘤外还要排除胃神经鞘瘤的可能性。

Abstract:

Objective To improve detectable rate of gastric schwannoma by endoscopic ultrasonography (EUS). Method Clinical data and endoscopic ultrasonography (EUS) imaging features of 4 cases were retrospectively analyzed which diagnosed as gastric schwannoma pathologically and immunohistochemically while diagnosed as gastric stromal tumor by EUS from May 2008 to June 2015 and reviewed the literature. Results 4 cases of gastric schwannomas are female and benign, all 4 lesions are solitary, 3 in gastric body, and 1 in fundus by endoscopic. By EUS, all lesions are originated from muscularis propria, hypoechoic change, even echoes and clear board without calcification or cystic changes. 2 cases have halo artifacts around the lesion. Literature review found that gastric schwannoma tended to occur in female, halo artifacts could be the feature of gastric schwannoma, calcification or cystic changes were rare in gastric schwannoma which were common in gastric stromal tumors. Conclusion It was difficult to distinguish gastric schwannoma and gastric stromal tumors that originated from muscularis propria by EUS. For female patients with lesions originated from muscularis propria, originated from muscularis propria and occurred in gastric body, it was necessary to observe lesions whether there was being calcification or cystic and halo artifacts. Integrated all these performance, we should be in consideration of gastric stromal tumors, meanwhile, excluding the possibility of gastric schwannoma.