光谱CT多定量参数对胃癌Lauren分型的诊断价值

The diagnostic value of spectral CT multiple quantitative parameters in Lauren's classification of gastric cancer

目的:探究双层探测器光谱CT多定量参数术前对胃癌Lauren分型的诊断价值。方法:收集48例术前在双层探测器光谱CT上行腹部增强检查且术后病理确诊为胃腺癌的患者,获取双层探测器光谱CT多定量参数及术后病理资料。按Lauren分型将入组病例分为三组,其中弥漫型17例,混合型21例,肠型10例。通过后处理软件得到碘浓度图及有效原子序数图,测量胃癌病灶及同层面腹主动脉期及静脉期的碘浓度及有效原子序数,计算标准化碘浓度及标准化有效原子序数。比较增强各期不同分型间各参数值的差异,对有统计学意义的参数绘制其受试者工作特征(receiver operating characteristic,ROC)曲线评估各参数的诊断效能,按约登指数为最大原则得出诊断阈值及曲线下面积(area under curve,AUC)。结果:弥漫型胃癌的各项参数值均高于肠型及混合型胃癌,弥漫型与混合型、弥漫型与肠型差异均具有统计学意义(P<0.05),而混合型与肠型除动脉期标准化有效原子序数差异具有统计学意义(P<0.05)外,余各参数值差异均无统计学意义(P>0.05)。动脉期及静脉期碘浓度、标准化碘浓度、有效原子序数及标准化有效原子序数诊断弥漫型胃癌的AUC分别为0.758、0.819、0.739、0.861及0.889、0.825、0.832、0.881;诊断阈值分别为1.26、0.12、7.91、0.75及1.81、0.52、8.28、0.91;动静脉期碘浓度、标准化碘浓度中,静脉期AUC最大;动静脉期有效原子序数、标准化有效原子序数中,静脉期AUC最大。结论:双层探测器光谱CT碘浓度及有效原子序数可为术前鉴别胃癌Lauren分型提供更多信息,具有一定的临床价值。

Objective:To explore the diagnostic value of dual-detector spectral CT multi-quantitative parameters in Lauren's typing of gastric cancer before surgery.Methods:Collect 48 patients who underwent preoperative abdominal enhancement examination using dual detector spectral CT and were pathologically diagnosed with gastric adenocarcinoma,and obtain multi-quantitative parameters of dual detector spectral CT and postoperative pathological data.According to Lauren's classification,the enrolled cases were divided into three groups,including 17 cases of diffuse type,21 cases of mixed type,and 10 cases of intestinal type.Obtain iodine maps and effective atomic number maps through post-processing software,measure the iodine concentration and effective atomic number of gastric cancer lesions,as well as the arterial and venous phases of the abdominal aorta at the same level,and calculate the normal iodine concentration and effective atomic number.Compare and enhance the differences in parameter values between different subtypes in different stages,draw the receiver operating characteristic curve(ROC) for statistically significant parameters,evaluate the diagnostic efficacy of each parameter,and obtain the diagnostic threshold and area under curve(AUC) based on the principle of maximizing the Jordan index.Results:The parameter values of diffuse gastric cancer were higher than those of intestinal and mixed gastric cancer,and the differences between diffuse and mixed gastric cancer,diffuse and intestinal cancer were statistically significant(P < 0.05).However,there was no statistically significant difference in the values of the other parameters between the mixed type and the intestinal type,except for the difference in normal effective atomic numbers during the arterial phase(P < 0.05).The AUC of arterial and venous iodine concentration,normal iodine concentration,effective atomic number,and normal effective atomic number for diagnosing diffuse gastric cancer was 0.758,0.819,0.739,0.861 and 0.889,0.825,0.832,0.881,respectively.The diagnostic thresholds were 1.26,0.12,7.91,0.75 and 1.81,0.52,8.28,0.91,respectively.Among the iodine concentration and normal iodine concentration in the arteriovenous phase,the AUC in the venous phase was the highest.Among the effective atomic numbers and normal effective atomic numbers in the arteriovenous phase,the AUC in the venous phase was the largest.Conclusion:The dual-layer detector spectral CT iodine concentration and effective atomic number can provide more information for preoperative differentiation of Lauren's classification of gastric cancer,and have certain clinical value.