【摘要】 目的 探讨PET/CT早期显像及延迟显像（双时相）在结直肠癌淋巴结转移中的应用价值。方法 选取行双时相PET/CT的82例结直肠癌患者共183枚淋巴结作为研究对象，以手术病理结果为金标准，按照淋巴结是否转移分为转移淋巴结组（n=52例，112枚）、未转移淋巴结组（n=30例，71枚）。测量2组PET/CT早期显像淋巴结代谢参数[SUVmaxL₁、SUVpeak、SUVmean、MTV、TLG、病灶SUVmaxT、长短径比（L/D）、肝脏SUVmaxH、腹主动脉SUVmaxA]及PET/CT延迟显像淋巴结代谢参数[SUVmaxL₂、滞留指数（RI）],计算△SUVmax（SUVmaxL₂-SUVmaxL₁）。比较2组各参数的差异，单时相与双时相PET/CT代谢参数的Logistic多因素分析，建立单时相与双时相PET/CT代谢参数联合预测诊断模型，应用受试者工作特征（ROC）曲线确定最佳阈值，并比较单时相、双时相PET/CT联合预测模型的诊断效能。结果 结直肠癌转移淋巴结组SUVmaxL₁、SUVpeak、SUVmean、MTV、SUVmaxL₁T、 SUVmaxL₁H、SUVmaxL₁A、SUVmaxL₂、RI、△SUVmax均高于未转移淋巴结组（P<0.05）,但L/D低于未转移淋巴结组（P<0.05）。Logistic多因素分析结果显示，单时相PET/CT代谢参数SUVpeak、L/D是预测结直肠癌淋巴结转移的独立因素（P<0.05）,双时相PET/CT代谢参数SUVmaxL₂是预测结直肠癌淋巴结转移的独立因素（P<0.05）。ROC曲线显示，单时相PET/CT联合预测模型诊断结直肠癌患者淋巴结转移的AUC为0.859、特异度为80.4%、敏感度为77.5%,双时相PET/CT联合预测模型对结直肠癌患者淋巴结转移AUC为0.877、特异度为88.4%、敏感度为83.1%,单时相、双时相PET/CT联合预测模型对结直肠癌患者淋巴结转移均有一定的诊断价值，但双时相PET/CT联合预测模型诊断价值高于单时相PET/CT联合预测模型诊断价值（P<0.05）。结论 双时相PET/CT联合预测诊断模型在结直肠癌淋巴结转移诊断中具有较高的应用价值，能够准确评估淋巴结转移，提高诊断效能，值得推广。更多还原

【Abstract】 Objective To evaluate the value of positron emission tomography/computed tomography（PET/CT） imaging at an early and delayed phase（dual-phase imaging） in lymph node metastasis of colorectal cancer.Methods 82 colorectal cancer patients with 183 lymph nodesunderwent dual-phase PET/CTwere selected.Taking surgical and pathological results as the gold standard, patients were classified into metastatic lymph node group（n=52,112nodes） and non-metastatic lymph node group（n=30,71nodes） according to the presence or absence of lymph nodes metastasis.The following parameters of PET/CT imaging at an early and delayed phasewere calculated: the maximum, peak, andmean standardized uptake value（SUVmaxL₁,SUVpeak, and SUVmean, respectively）,total tumour volume（MTV）,total lesion glycolysis（TLG）,SUVmax of primary tumor（SUVmaxT）,length to diameter ratio（L/D）,SUVmax of hepar index（SUVmaxH）,SUVmax ofarota（ SUVmaxA）,SUVmaxL₂,retention index（RI）,and △SUVmax（SUVmaxL₂-SUVmaxL₁）.The above parameters were compared between two groups.Logistic multivariate analysis was conducted on the metabolic parameters measured by PET/CT.A predictive diagnostic model was established based on the PET/CT metabolic parameters, and the receiver operating characteristic（ROC） curve was used to determine the optimal cutoff values of numerical variables.Then the diagnostic efficiency of single-phase and dual-phase PET/CT model was evaluated.Results The values of SUVmaxL₁,SUVpeak, SUVmean, MTV,SUVmaxL₁T,SUVmaxL₁H,SUVmaxL₁A,SUVmaxL₂,RI and △SUVmax of metastatic lymph node group were all larger than those of non-metastatic lymph node group（P<0.05）,while L/D ratio was smaller than that of non-metastatic lymph node group（P<0.05）.Logistic multivariate analysis denoted that single phase PET/CT metabolic parameters SUVpeak and L/D were independent factors for predicting lymph node metastasis of colorectal cancer（P<0.05）,while dual-phase PET/CT metabolic parameter SUVmaxL₂ was an independent factor for predicting lymph node metastasis of colorectal cancer（P<0.05）.ROC curve indicated that the combined detection of the single phase PET/CT metabolic parameters had an AUC of 0.859,specificity of 80.4% and sensitivity of 77.5% for the diagnosis of lymph node metastasis in patients with colorectal cancer, and the combined detection of the dual phase PET/CT metabolic parameters had an AUC of 0.877,specificity of 88.4% and sensitivity of 83.1% for the diagnosis of lymph node metastasis in patients with colorectal cancer.Both single-phase and dual-phase PET/CT combined prediction models had certain diagnostic value for lymph node metastasis in patients with colorectal cancer, but the diagnostic value of dual-phase PET/CT combined prediction model was higher than that of single-phase PET/CT combined prediction model（P<0.05）.Conclusions The dual phase PET/CT prediction diagnostic model is of great application value in the diagnosis of lymph node metastasis in colorectal cancer, which can accurately assess lymph node metastasis and improve diagnostic efficacy, and is worth promoting.更多还原