MDCT窗技术联合MPR在T1和T2期胃癌中的鉴别诊断价值

The differential diagnostic value of MDCT window technique combined with MPR images in T1 and T2 gastric cancer

目的:探讨MDCT窗技术联合多平面重建(MPR)在T1和T2期胃癌中的鉴别诊断价值。方法:回顾性分析经手术病理证实的154例T1期胃癌、78例T2期胃癌患者的临床病理特征(主要包括肿瘤位置、最大径、胃切除类型和病理类型等)。由两位放射科医生分别基于窄窗宽图像(窗宽180 HU,窗位90 HU)、腹窗图像(窗宽350 HU,窗位50 HU)和窄窗宽结合MPR图像进行术前胃癌T分期。使用χ^(2)检验评估年龄、性别等临床病理因素与胃癌分期的单变量相关性。采用Z检验分别比较窄窗宽组与腹窗组、窄窗宽结合MPR组与腹窗组诊断T1期胃癌的阳性预测值(PPV)、特异度(SPE)、敏感度(SEN)和阴性预测值(NPV)。采用Kappa检验评估两位阅片者对胃癌T分期诊断的一致性。结果:两组胃癌患者在肿瘤位置、最大径、胃切除类型、病理类型、pN分期、pTNM分期、淋巴管浸润及神经浸润存在显著性统计学差异(P<0.05)。窄窗宽组均较腹窗组诊断T1期胃癌有较高的SEN(86%vs.59%,86%vs.53%)、NPV(71%vs.47%,72%vs.45%);与腹窗组比较,窄窗宽结合MPR组诊断T1期胃癌的SEN(91%vs.59%,92%vs.53%)、NPV(83%vs.47%,85%vs.45%)和PPV(93%vs.81%,93%vs.82%)较高(P均<0.025)。对腹窗组、窄窗组、窄窗宽结合MPR组进行胃癌T分期评估时,观察者之间的一致性极高(Kappa=0.831、0.836、0.868)。结论:MDCT窗技术适用于T1及T2期胃癌的鉴别诊断,窄窗宽技术联合MPR具有较高的灵敏度、阳性预测值及阴性预测值。

Objective:The purpose of this study was to investigate the value of MDCT window technique combined withmulti-planar reformation(MPR)images in the differential diagnosis of T1-and T2-stage gastric cancer.Methods:The preoperative clinicopathological features of 154 patients with stage T1 gastric cancer and 78 patients with stage T2 gastric cancerconfirmed by pathology were analyzed retrospectively,including tumor location,maximum diameter,type of gastrectomy,and patholo-gical type.T staging of gastric cancer was performed by two radiologists independently in the narrow window width group(window width:180HU,window level:90HU),the abdominal window group(window width:350HU,window level:50HU),and the narrow window width combined with MPR group.The univariate correlation between clinicopathological factors such as age and gender and gastric cancer stage were performed byχ^(2)-test.Z-test was used to compare thespecificity(SPE),sensitivity(SEN),positive predictive value(PPV)and negative predictive value(NPV)between the narrow window width group and abdominal windowgroup,and the narrow window width combined with MPR group,and abdominal window groupin the diagnosis of T1 gastric cancer.The Kappa test was used to evaluate the agreement between the two readers in the T staging of gastric cancer.Results:There were significant differences in tumor location,maximum diameter,type of gastrectomy,pathological type,pN stage,pTNM stage,lymphatic vessel invasion,and nerve invasion between the two groups(P<0.05).Compared with the abdominal window group,the narrow window width group had higher SEN(86%vs.59%,86%vs.53%)and NPV(71%vs.47%,72%vs.45%).Compared with the abdominal window group,the narrow window width combined with MPR group had higher SEN(91%vs.59%,92%vs.53%),NPV(83%vs.47%,85%vs.45%)and PPV(93%vs.81%,93%vs.82%)with statistical differences(all P<0.025).A Kappa test indicated high inter-observer agreement for T staging with the narrow window width group,the abdominal window group,and the narrow window width combined with MPR group(Kappa=0.831,0.836,and 0.868).Conclusion:The MDCT window technique is suitable for the differential diagnosis of the T1-and T2-stage gastric cancer.Combined with MPR images,the narrowwindow technique has high sensitivity,positive predictive value and ne-gative predictive value.