中国癌症杂志 ›› 2016, Vol. 26 ›› Issue (7): 629-634.doi: 10.19401/j.cnki.1007-3639.2016.07.011

• 论著 • 上一篇    下一篇

MRI平扫结合DWI在胃癌术前T分期及淋巴结转移上的价值

耿晓丹,于丽娟,陈慕楠,王文志,李迎辞   

  1. 哈尔滨医科大学附属肿瘤医院PET/CT-MRI 中心,黑龙江 哈尔滨 150081
  • 出版日期:2016-07-30 发布日期:2016-08-22
  • 通信作者: 于丽娟 E-mail:yulijuan2003@126.com

Diagnostic performance of diffusion-weighted magnetic resonance imaging for preoperative T staging and metastatic lymph nodes of gastric adenocarcinoma

GENG Xiaodan, YU Lijuan, CHEN Munan, WANG Wenzhi, LI Yingci   

  1. Harbin Medical University Cancer Hospital, Department of PET/CT-MRI Center, Harbin 150081, Heilongjiang Province, China
  • Published:2016-07-30 Online:2016-08-22
  • Contact: YU Lijuan E-mail: yulijuan2003@126.com

摘要: 背景与目的:胃癌严重影响人类健康,术前准确T分期及淋巴结转移的预测有利于患者治疗方案的选择及预后。该研究旨在探讨3.0 T磁共振(magnetic resonance imaging, MRI)平扫结合弥散加权成像(diffusion-weighted imaging,DWI)对术前胃癌T分期及淋巴结转移的诊断价值。方法:该研究前瞻性开展了胃癌3.0 MRI平扫+DWI成像研究,其中35例胃癌患者被作为研究对象。这些患者均在术前进行T分期及淋巴结良恶性的评估,并与手术病理结果相对照。MRI结合DWI与手术病理T分期结果一致性分析采用Kappa检验。在MRI上分别测量淋巴结的的长径、短径、表观扩散系数(apparent diffusion coefficient, ADC)值、相对肌肉ADC(relative of muscle’s ADC,rADCm)值(rADCm =ADC淋巴结值/ADC左侧竖脊肌值)以及相对原发灶ADC(relative of primary tumor’s ADC,rADCp)值(rADCp =ADC淋巴结值/ADC胃癌原发灶值)等指标。采用独立样本t检验比较胃癌转移淋巴结与非转移淋巴结各项观测指标间有无统计学差异,利用ROC曲线下面积的大小评估各项指标对胃癌淋巴结转移的诊断效能。结果:35例患者MRI结合DWI术前 T分期准确率分别为:T1期75%,T2期100%;T3期76.47%;T4期75.00%。良恶性淋巴结的长径、短径、ADC值、rADCm值及rADCp之间差异均有统计学意义(P<0.05)。受试者工作特征(receiver operating characteristic, ROC)曲线显示rADCm值曲线下面积最大,诊断效能最高。淋巴结长径、短径、ADC值、rADCm值和rADCp值的最佳截断点分别为9.55 mm、6.05 mm、0.934×10-3mm2/s、0.60和1.083,灵敏度与特异度分别为59.00%和73.10%、59.00%和69.80%、82.60%和88.50%、83.70%和84.60%、78.20%和80.80%。结论:MRI结合DWI对胃癌术前T分期及淋巴结良恶性的评估具有重要指导意义。

关键词: 胃癌, 磁共振成像, T分期, 淋巴结, 表观扩散系数

Abstract: Background and purpose: Gastric cancer impacts human health seriously. Accurate preoperative assessment of T staging and metastatic lymph nodes of gastric cancer was beneficial to patients’ treatment options and their prognosis. The purpose of this study was to evaluate the diagnostic performance of diffusion-weighted magnetic resonance imaging for preoperative assessment of T staging and metastatic lymph nodes in patients with gastric cancer. Methods: This study selected 35 gastric cancer patients met the criteria for this prospective study. They all underwent gastric 3.0 T MRI+DWI imaging scan. These patients’ T stage and metastatic lymph nodes were evaluated before the surgery, with the reference of post-operative histopathological findings. Kappa consistency test was used to assess the consistency of T staging between the two methods. This study analyzed short axis diameter, long axis diameter and apparent diffusion coefficient (ADC) values of lymph nodes, relative of muscle’s ADC (rADCm) values (rADCm=ADC values of lymph nodes/ADC values of right erector spinae), and relative of primary tumor’s ADC (rADCp) values (rADCp=ADC values of lymph nodes/ADC values of primary tumor) on MRI image. Independent samples test was used to assess the difference between metastatic lymph nodes and benign lymph nodes. The receiver operating characteristic (ROC) curve was generated to evaluate the accuracy of diffusion-weighted magnetic resonance imaging (MRI) for preoperative assessment of metastatic lymph nodes of gastric cancer. Results: The accuracy of diffusion-weighted MRI for T stages was 77.14%, 75% for T1, 100% for T2, 76.47% for T3 and 75.00% for T4 and respectively. There were statistically significant differences in the long axis diameter, the short axis diameter, ADC value, rADCm and rADCp between metastatic lymph nodes and benign lymph nodes (P<0.05). The area under the ROC curve of rADCm was greater than thats of other criteria, so rADCm was the most significant parameter. The best discriminative cut-off value of long axis, short axis, ADC value, rADCm value and rADCp value were 9.55 mm, 6.05 mm, 0.934×10-3 mm2/s, 0.60 and 1.083, respectively. The sensitivity and specificity were 59.00% and 73.10%, 59.00% and 69.80%, 82.60% and 88.50%, 83.70% and 84.60%, 78.20% and 80.80%, respectively. Conclusion: Diffusion-weighted MRI has great significance for preoperative assessment of T staging and metastatic lymph nodes of gastric cancer.

Key words: Gastric cancer, MRI, T staging, Lymph node, ADC