DWI及ADC值在胃癌淋巴结性质判断及化疗疗效评估中的作用

The role of DWI and ADC value in judging the nature of lymph nodes in gastric cancer and monitoring the chemotherapy effect

目的:探讨扩散加权成像(DWI)及表观扩散系数(ADC)值在进展期胃癌淋巴结性质判断中的价值,进一步探讨其在化疗疗效动态监测中的应用价值。方法:44例伴有可测淋巴结的进展期胃癌患者,分别于化疗前、化疗后3、7、30和60d行MRI-DWI检查,测量化疗前和化疗后60d每个淋巴结的长径、垂直短径,以及化疗前和化疗后各时间点每个淋巴结的ADC值,化疗后60d行手术切除及淋巴结清扫,分组切除淋巴结共1258枚送病理活检,标记淋巴结组别,按照病理结果分为全阳性组(231枚,整组切除之淋巴结均有转移)和全阴性组(495枚,整组切除之淋巴结均无转移),分析比较两组间化疗前淋巴结长径、短径及ADC值差异,分析全阳性组中各疗效组化疗前后不同时间点ADC值差异并进行统计学处理。结果:化疗前全阳性组与全阴性组淋巴结长径、短径及ADC值差异均有统计学意义(P<0.05)。全阳性组中部分有效组(PR组)及稳定组(SD组)化疗前、化疗后3、7、30和60dADC值均呈上升趋势,化疗前与化疗后各时间点的ADC值差异均有统计学意义(P<0.05);完全有效组(CR组)可测时间点内随时间进展ADC值也呈上升趋势,化疗前与化疗后各可测时间点的ADC值差异均有统计学意义(P<0.05)。结论:DWI及ADC值可初步判断胃癌患者可测淋巴结的性质,并可动态观察和早期定量监测胃癌患者转移性淋巴结的化疗疗效。

Objectives To investigate the value of diffusion weighted imaging （DWI） and apparent diffusion coefficient （ADC） value in judging the nature of lymph nodes in advanced gastric cancer and further to investigate the application value in monitoring the curative effect dynamically after chemotherapy. Methods： 44 patients with advanced gastric cancer having measurable lymph nodes. MRI-DWI were carried out before and 3d, 7d, 30d, 60d after chemotherapy respectively. The long dimension and vertical short dimension of each lymph node were measured before and 60d after chemotherapy, also the ADC value of each lymph node was measured before and at various time points after chemotherapy. Gastrectomy and iymphade- nectomy were performed 60d after chemotherapy. Altogether 1258 lymph nodes were excised and marked in groups, then pathology exanimation were performed. According to pathology results, there were totally positive group （231 lymph nodes, all had metastases） and totally negative group （495 lymph nodes, all without metastases）. The differences of long dimension, vertical short dimension and ADC values between the two groups of lymph nodes before chemotherapy were analyzed, as well as the differences of lymph node ADC values in the totally positive groups with curative effect before and at different time-points after chemotherapy. Statistic analysis were performed. Results： The long dimension, vertical short dimension and ADC values of lymph nodes in the totally positive group and totally negative group before chemotherapy showed significant statistic differences （P〈0.05）. Of the totally positive group,the ADC values in PR and SD sub-groups showed a tendency of increasing before and 3d, 7d, 30d, 60d after chemotherapy, with significant statistic difference （P〈0.05）. The ADC values of lymph nodes in CR group also showed an upward trend at various measurable time points,with significant statistics differences before and at each measurable time point after chemotherapy （P〈0.05）. Conclusion： DWI and ADC values can be used to preliminarily judge the nature of measurable lymph node for gastric cancer patients and can he used to early and dynamically observe as well as quantitatively monitor the chemotherapy effect of metastatic lymph node in gastric cancer.