DCE-CT鉴别诊断胃异位胰腺和间质瘤的价值

Value of DCE-CT in differential diagnosis of gastric ectopic pancreas and stromal tumors

目的:探讨动态增强CT(DCE-CT)对胃部异位胰腺与间质瘤的鉴别诊断价值。方法:回顾性分析经手术病理证实的17例胃部异位胰腺及40例胃间质瘤患者的临床及影像资料。比较两组患者的年龄、性别及病灶的形态、部位、生长方式、长径、短径、边界、强化模式、胃黏膜强化、钙化、平扫和三期增强扫描的CT值和"导管征"显示率等征象的差异。结果:异位胰腺组患者的平均年龄小于间质瘤组(50.12 vs.59.70岁;P=0.001)。异位胰腺多位于胃窦部(70.6%)、强化不均匀(52.9%)、边界欠清(29.4%)、长径-短径比值(LD/SD)相对较大;间质瘤多位于胃底部(67.5%)、呈均质性强化(75.0%)、边界清晰(97.5%)、LD/SD相对较小,四个征象的组间差异均具有统计学意义(P=0.001、0.041、0.011和0.002)。异位胰腺与间质瘤在动脉期、静脉期的相对CT值(病灶CT值/腰大肌CT值)及强化程度的差异均具有统计学意义(P=0.006、0.008、0.004和0.043)。异位胰腺组中约52.9%的患者出现“导管征”。联合患者年龄、病灶的位置、囊实性和LD/SD四项指标进行鉴别诊断,ROC曲线下面积为0.941,敏感度和特异度分别为100%和88.2%。结论:胃部异位胰腺的临床和CT征象与胃部间质瘤之间有一定差异,多指标联合诊断可提高诊断效能。

Objective:To investigate the value of dynamic contrast-enhanced CT(DCE-CT)in the differential diagnosis of ectopic pancreas and stromal tumors in the stomach.Methods:The clinical and imaging data of 17 patients with gastric ectopic pancreas and 40 patients with gastric stromal tumor confirmed by surgery and pathology were retrospectively analyzed.The age and sex of the patients and the shape,location,growth pattern,long diameter(LD),short diameter(SD),boundary,enhancement mode,gastric mucosal enhancement,calcification,"catheter sign"and enhanced CT values of the lesions in the two groups were observed and compared statistically.Results:The mean age in the ectopic pancreas group was lower than that in the stromal tumor group(50.12 vs.59.70 years;P=0.001).The ectopic pancreas was mostly located in the antrum of the stomach(70.6%),with heterogeneous enhancement(52.9%),ill-defined border(29.4%),and relatively larger LD to SD ratio(LD/SD);the stromal tumor was mostly located at the bottom of the stomach(67.5%),with homogeneou enhancement(75%),well-defined border(97.5%),and relatively smaller LD/SD.There were statistically significant difference in these four features between the two groups(P=0.001,0.041,0.011 and 0.002).On contrast enhanced CT images,statistically significant differences was found in relative CT values(ratio of CT values of the tumor to psoas magnus)and enhanced CT values in arterial and venous phase between the ectopic pancreas and stromal tumors(P=0.006,0.008,0.004,0.043)."Catheter sign"was found in approximately 52.9%of patients in the ectopic pancreas group.The combined features(lesion component,age,LD/SD and location)provided acceptable diagnostic performance(100%of sensitivity and 88.2%of specificity)for differentiation of ectopic pancreas from stromal tumors.Conclusion:The clinical and CT features of ectopic pancreas and stromal tumor are quite diffe-rent,and the combination of the indexes is of great value for the differential diagnosis.