高分辨薄层直肠核磁共振新序列（3.0T RESOLVE-DWI）在直肠癌临床分期中的价值评估

目的探讨高分辨薄层直肠MRI新序列（3.0T RESOLVE-DWI）在直肠癌术前临床分期中的准确性。 方法回顾性分析四川大学华西医院75例行术前高分辨薄层直肠MRI新序列扫描的直肠癌根治性切除术的病例，分析MRI影像中肿瘤浸润深度（T），并测量肿瘤及周围淋巴结（N）的表观弥散系数（ADC）值。以术后病检结果为金标准，分析MRI评估T分期的准确性，ADC值与肿瘤T、N分期及分化程度的相关性。 结果MRI从T1到T4期的诊断准确性在未行新辅助治疗的患者中分别为0%、38.1%、72%、14.3%（κ=0.200），在行新辅助治疗的患者中分别为50%、33%、75%、0%（κ=0.270）。肿瘤ADC值与T分期（F=0.074，P=0.929；F=0.737，P=0.496）、肿瘤分化程度（F=1.889，P=0.783；F=4.385，P=0.627）在两组均无显著相关性。在未行新辅助治疗的患者中，淋巴结ADC值在术后病理淋巴结阳性组高于淋巴结阴性组（F=0.073，P=0.012），而在新辅助治疗组差异无统计学意义（F=0.035，P=0.793）。 结论直肠癌高分辨薄层MRI新序列对T3期直肠癌的诊断准确率高，整体准确率较低；新序列ADC值对于直肠癌N分期的评估具有一定价值，还需进一步研究验证。

Evaluation of high resolution thin slice rectal magnetic resonance imaging (3.0T RESOLVE-DWI) in clinical staging of rectal cancer

ObjectiveTo evaluate the efficacy of MRI of high resolution layer in rectal cancer at 3.0T magnetic resonance (MR) for diagnosing rectal cancer, and analyze the relationship between apparent diffusion coefficient (ADC) values and pathological results of tumor. MethodsWe retrospectively analyses 75 patients with radical surgical and pathological proved rectal cancer. All patients received high resolution layer rectal 3.0T MRI, to evaluate the correlation between MRI and pathology by estimating invasive depth and measuring the ADC value in different type of group. ResultsThe diagnostic accuracy of high resolution layer rectal MRI for pathological changes in T1, T2, T3, and T4 was 0%, 38.1%, 72%, 14.3% in the group of non-preoperative therapy, and 50%, 33%, 75%, 0% in the group of preoperative therapy. There was poor consistency between T stage of MRI and pathology whether in group of non-preoperative therapy (κ=0.200) or preoperative therapy (κ=0.270). There was no significant correlation between the ADC value of tumors and groups of various T stage. There was also no significant correlation between the ADC value of tumors and groups of various differentiation grades. Non-preoperative therapy group (F=0.074, P=0.929; F=0.737, P=0.496) and preoperative therapy group (F=1.889, P=0.783; F=4.385, P=0.627). There was a significant difference between the patients with lymph metastasis and those without lymph metastasis in non-preoperative therapy group (F=0.073, P=0.012), and there was no significant difference in preoperative therapy group (F=0.035, P=0.793). ConclusionThe diagnostic accuracy of high resolution layer rectal MRI for pathological changes in T3 is high, but the overall accuracy rate is low. ADC value of high resolution layer rectal MRI has some value in evaluated the lymph metastasis and need further study.