目的：探讨双源双能量CT（以下简称双能量CT）扫描结果中病灶标准化碘值与非标准化碘值间是否有差异,并评估碘值在进展期胃腺癌化疗疗效评价中的应用价值。方法：对48例经胃镜病理检查证实为腺癌的患者行新辅助化疗,分析化疗前后双能量CT扫描图像,计算病灶化疗前、后门脉期及延迟期的标准化碘值变化率及非标准化碘值变化率;并以实体瘤疗效评价标准（Response Evaluation Criteria in Solid Tumors, RECIST）1.1分为反应组与非反应组,比较2组间化疗前、后各碘值及其变化率的差异。结果：①门脉期所有患者胃原发灶的各非标准碘值变化率与标准化碘值变化率相比,差异均无统计学意义（P>0.05）,延迟期也具有相同的表现（P>0.05）。②反应组化疗后病灶各碘值在门脉期均明显小于非反应组[数值用（均数±标准差）或中位数（四分位差）表示][化疗后门脉期碘摄取浓度,（1.71±0.49） mg/mL 比（2.15±0.55） mg/mL,P=0.008;化疗后标准化门脉期碘摄取浓度,0.30±0.09比0.38±0.10,P=0.003;化疗后门脉期总碘摄取量,18.30 mg（27.15 mg）比81.55 mg（81.20 mg）,P<0.001;化疗后标准化门脉期总碘摄取量,15.86（22.65）比47.97（64.05）,P<0.001]。③反应组病灶的总碘摄取量减少率在门脉期及延迟期均明显大于非反应组[化疗前后门脉期总碘摄取量减少率,-83.34%（21.05%）比-39.82%（47.90%）,P<0.001; 化疗前后门脉期标准化总碘摄取量减少率,-80.28%（19.61%）比-42.33%（41.12%）,P<0.001;化疗前后延迟期总碘摄取量减少率,-80.66%（19.97%）比-36.99%（37.71%）,P<0.001;化疗前后延迟期标准化总碘摄取量减少率,-79.57%（24.89%）比-37.79%（36.48%）,P<0.001]。结论：病灶化疗前、后的标准化碘值变化率与非标准化碘值变化率间差异无统计学意义,利用双能量CT扫描测得的病灶化疗后碘值及各碘值变化率（尤其是病灶的总碘摄取量减少率）在评估进展期胃腺癌新辅助化疗疗效中有一定价值。
Objective: To assess the iodine value in dual source dual energy CT (DSDECT) for evaluating the efficacy of neoadjuvant chemotherapy on advanced gastric adenocarcinoma and comparing the standardized iodine value and non-standardized iodine value in lesions as well as the difference in reduction ratio of iodine value before and after neoadjuvant chemotherapy. Methods: A total of 48 patients with pathologically confirmed gastric adenocarcinoma via endoscopy were enrolled and neoadjuvant chemotherapy was conducted. The DSDECT images before and after chemotherapy were analyzed to compare the difference between the reduction ratio of standardized iodine values (which were normalized with abdominal aorta) and non-standardized iodine values in portal phase and delayed phase. According to RECIST1.1 criteria, patients were divided into response group and non-response group. The differences in iodine value as well as reduction ratio of iodine value of lesions before and after neoadjuvant chemotherapy were compared between response and non-response groups. Results: ① There were no significant differences in the reduction ratio of standardized iodine values and non-standardized iodine values before and after neoadjuvant chemotherapy in both portal phase and delayed phase(P>0.05). ② The iodine values after neoadjuvant chemotherapy in the response group were significantly lower than those of the non-response group in the portal phase [values are expressed as (mean ± standard deviation) or median (guartile deviation)][iodine uptake in portal phase(IU-P), （1.71±0.49） mg/mL vs （2.15±0.55）mg/mL, P=0.008; normalized iodine uptake in portal phase(NIU-P), （0.30±0.09） vs （0.38±0.10）, P=0.003; total iodine uptake in portal phase (TIU-P): 18.30 mg（27.15 mg） vs 81.55 mg（81.20 mg）, P<0.001; normalized total iodine uptake in portal phase (NTIU-P): 15.86（22.65） vs 47.97（64.05）, P<0.001]. ③ The reduction ratio of total iodine uptake before and after neoadjuvant chemotherapy in response group were significantly higher than those in non-response group in both portal and delayed phase [ΔTIU-P, -83.34%（21.05%） vs -39.82%（47.90%）, P<0.001; ΔNTIU-P, -80.28%（19.61%） vs -42.33%（41.12%）, P<0.001; ΔTIU-D, -80.66%（19.97%） vs -36.99%（37.71%）, P<0.001; ΔNTIU-D, -79.57%（24.89%） vs -37.79%（36.48%）, P<0.001]. Conclusions: The iodine values and the reduction ratio of the iodine values after neoadjuvant chemotherapy obtained from DSDECT can be helpful for evaluating the efficacy of neoadjuvant chemotherapy on advanced gastric adenocarcinoma.
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