膀胱神经内分泌肿瘤的CT表现

CT Imaging Features of Bladder Neuroendocrine Tumor

目的探讨膀胱神经内分泌肿瘤(NET)的CT表现特征,以提高诊断准确率。方法回顾性分析经病理证实的10例膀胱NET的临床、病理及CT资料,在CT图像上评估肿瘤位置、大小、形态、密度、强化特点及其与周围结构关系、淋巴结或远处转移等情况,并与病理结果相对照。结果副神经节瘤2例,表现为类圆形、密度均匀的软组织肿块,边界清,宽基底附着于膀胱壁;增强扫描动脉期明显强化,强化幅度约60~70 HU,1例见增多迂曲血管影。类癌2例,均表现为类圆形,密度均匀,边界清,其中1例以窄蒂与膀胱壁相连,局部见斑点状钙化;增强扫描动脉期明显强化,强化程度类似于同层面髂动脉。小细胞神经内分泌癌6例,表现为不规则形、类圆形软组织肿块,边界不清,其中密度不均5例,内含不同程度坏死,2例见斑片状钙化;增强扫描表现为轻~中度不均匀强化,强化幅度<40 HU;病变周围脂肪间隙模糊6例,邻近膀胱壁增厚4例,合并淋巴结肿大2例。结论CT动态增强扫描对膀胱NET的明确诊断有一定的帮助,但最终确诊仍依赖于病理和免疫组织化学检查。

Objective To analyze the CT imaging features of bladder neuroendocrine tumor(NET),so as to improve its diagnostic accuracy.Methods The clinical,pathological and CT imaging findings of 10 bladder neuroendocrine tumors,confirmed by pathology were analyzed retrospectively.CT imagings features were used to evaluate tumor location,size,shape,density,enhancement characteristics,invasive capacity,lymph node or distant metastasis.And then they were compared with the pathology.Results Paraganglioma(2 cases).They were round in shape,well-circumscribed margin,homogeneous soft tissue density and broad-based attachment to the bladder wall.Both of them showed marked enhancement in arterial phase with the contrast enhancement magnitude of 60-70 HU.The increased and tortuous vessels were observed in one of the cases.Carcinoid(2 cases).They also showed a round shape,clear boundaries,and homogeneous soft tissue density.The narrow pedicle was connected to the bladder wall which had spotted calcification.They showed intense enhancement in arterial phase which was similar to the degree of iliac artery.Small-cell neuroendocrine carcinoma(6 cases):The masses all showed irregular or round shape with unclear boundaries.5 of the cases were heterogeneous with varying degrees of necrosis and 2 cases had patchy calcification.On contrast-enhanced scan,the mild to moderate enhancement was observed with the enhanced magnitude less than 40 HU.They had infiltrative growth with surrounding blurred fat space(n=6),thickened bladder wall(n=4),and enlarged lymph nodes(n=2).Conclusion CT dynamic contrast enhancement is helpful for the diagnosis of bladder NET.However,the final diagnosis still relies on pathology and immunohistochemistry examination.