目的 探讨MSCT对胃肠道神经内 分泌肿瘤(GI-NENs)的诊断价值。方法 参 照2010年WHO消化系统肿瘤分类和分级标 准，回顾分析38例经病理证实之胃肠道 神经内分泌肿瘤(GI-NENs)的临床资料及 MSCT表现特点。结果 38例患者G1肿瘤10 例，G2肿瘤4例，G3肿瘤24例。14例G1、 G2肿瘤患者中，12例平扫呈团块状及分叶 状低密度肿块，密度均匀，轮廓光整；2 例表现为不规则团片状低密灶，内有小点 片状钙化；发生于上消化道者影像表现为 动脉期显著强化，晚期强化密度减低；发 生于下消化道者病灶静脉期或平衡期达强 化高峰。结论 本组GI-NENs均无特异性临 床症状。G1及G2级肿瘤MSCT影像表现具有 一定特点，病灶显著强化，发生于上消化 道者具有呈“快进慢出”特征，下消化道 者强化高峰较晚；G3级肿瘤MSCT影像表现 与其它病理类型消化道恶性肿瘤不易鉴 别，需依靠病理学特征区分。

Objective To investigate the diagnostic value of MSCT for gastrointestinal neuroendocrine neoplasms, and to increase the diagnostic rate. Methods In accordance with the 2010 WHO classification standard of tumors in the digestive system, clinical data and MSCT characteristics of 38 patients with gastrointestinal neuroendocrine neoplasms (GI-NENs) are retrospectively analyzed, which are pathologically confirmed by surgery and colonoscopy. Results Out of 38 patients there are 10 classified as G1, 4 are in G2, and rest are G3. Among 14 cases of G1 and G2 cancer, CT images without contrast of 12 cases showed mass-like or lobulated low-density mass with even density and smooth contour. And CT images of the other 2 cases showed irregular patching low-density lesion, in which there was small spot calcification. CT images with contrast of GI-NENs in the upper digestive tract showed significant contrast in arterial phase, and the density reduction occurred in the late phase. The lesions in the lower gastrointestinal tract had significant contrast in the venous phase or in balance phase. Conclusion The GI-NENs of this study had no specific clinical symptoms. MSCT imaging of G1 and G2 tumors had certain characteristics. The lesions had significant contrast, which appeared enhancement pattern as "fast-in and slow-out" in the upper gastrointestinal tract and appeared the contrast peak late in the lower digestive tract. MSCT imaging findings of G3 tumors were difficult to differentiate with other gastrointestinal cancers, however, it can be detected by the pathological features.