扩散加权成像评估结直肠癌区域淋巴结转移预后相关因素分析

Diffusion Weighted Imaging in Evaluating the Prognosis of Colorectal Cancer Patients with Regional Lymph Node Metastasis

目的扩散加权成像(DWI)能显著提高对未出现体积增大的转移淋巴结的诊断能力,本研究旨在评估结直肠癌区域淋巴结转移DWI表现是否有助于评估患者的预后,并分析与预后有关的因素。资料与方法 47例结直肠癌患者行DWI检查后均行手术治疗,对照术后病理结果,确定区域转移性(DWI阳性)和非转移性(DWI阴性)淋巴结。比较DWI阳性和阴性患者5年无病生存率和整体生存率。评估患者各相关因素与预后的相关性,相关因素包括有无DWI诊断区域淋巴结转移(DWI阳性淋巴结)、DWI阳性最大淋巴结的短轴直径和长轴直径、DWI阳性淋巴结的数量。结果 47例患者中,DWI诊断区域淋巴结转移10例(21%),DWI阳性表现为淋巴结受侵犯,呈高信号。DWI阴性患者5年无病生存率和整体生存率明显高于DWI阳性患者(P<0.05)。最大转移淋巴结的短轴直径与发生远处转移有相关性(AUC=0.77,P<0.05),最高准确率为76%时的短轴直径为9 mm。最大转移淋巴结的短轴直径、长轴直径与整体生存率有相关性(AUC=0.84、0.75,P<0.05),最高准确率为85%时的短轴直径为9 mm,最高准确率为76%时的长轴直径为11mm。DWI阳性最大淋巴结短轴直径≤9 mm患者的5年无病生存率和整体生存率高于短轴直径>9 mm患者(P<0.05);长轴直径≤11 mm患者的5年无病生存率和整体生存率高于长轴直径>11 mm患者(P<0.05)。全部DWI阳性淋巴结均被切除的患者5年无病生存率高于DWI阳性淋巴结未被完全切除的患者(P<0.05)。结论 DWI阴性的患者预后更好;在DWI阳性患者中,转移淋巴结较小的患者预后更好。

Purpose Diffusion weighted imaging（DWI） can significantly improve the diagnosis of non-enlarged lymph node metastasis. This study aims to evaluate the correlation between the DWI findings and the prognosis, and to identify prognostic factors. Materials and Methods Forty-seven patients with colorectal cancer underwent MRI scan including DWI sequence before surgery. Imaging findings were compared with the pathologic results to determine the metastatic lymph nodes（DWI positive） or nonmetastatic lymph nodes（DWI negative）. Postoperative disease-free survival and overall survival for 5 years of the patients with DWI positive and DWI negative lymph nodes were compared. Correlation between the prognosis and the related factors were investigated including regional DWI-positive lymph nodes, short axis diameter and long axis diameter of the largest DWI-positive lymph node, and number of DWI-positive nodes. Results Of 47 patients,10（21%） patients had regional DWI-positive lymph nodes showed high signal intensity on diffusion-weighted images. The patients with regional DWI negative lymph nodes had a significant better five-year disease-free survival and overall survival（P〈0.05）. The short axis diameter of the largest DWI-positive lymph node was correlated with distant metastasis（AUC=0.77, P〈0.05）. The short axis diameter and long axis diameter of the maximum metastatic lymph nodes were correlated with overall survival（AUC=0.84 and 0.75, P〈0.05）. Five-year disease-free survival and overall survival of the patients with short axis diameter of the largest DWI-positive lymph node ≤ 9 mm were higher than the patients with lymph node short axis diameter 〉9 mm（P〈0.05）. Five-year disease-free survival and overall survival of the patients with long axis diameter of the largest DWIpositive lymph nodes ≤ 11 mm were higher than the patients with long axis diameter 11 mm（P〈0.05）. Five-year disease-free survival of the patients with all DWI positive lymph nodes resected was higher than the patient without DWI-positive lymph nodes resected（P〈0.05）. Conclusion The patients with regional DWI-negative lymph node had a better prognosis. Of the patients with DWI-positive lymph nodes, the patients with smaller lymph nodes have better prognosis than who have larger lymph nodes.