包含淋巴结转移风险因素的逻辑模型可提高直肠癌磁共振成像诊断的准确性。

A logistic model including risk factors for lymph node metastasis can improve the accuracy of magnetic resonance imaging diagnosis of rectal cancer.

作者信息

Ogawa Shimpei, Itabashi Michio, Hirosawa Tomoichiro, Hashimoto Takuzo, Bamba Yoshiko, Kameoka Shingo

机构信息

Department of Surgery II, Tokyo Women's Medical University School of Medicine, Shinjuku-ku, Tokyo, Japan E-mail :

出版信息

Asian Pac J Cancer Prev. 2015;16(2):707-12. doi: 10.7314/apjcp.2015.16.2.707.

DOI:10.7314/apjcp.2015.16.2.707

PMID:25684512

Abstract

BACKGROUND

To evaluate use of magnetic resonance imaging (MRI) and a logistic model including risk factors for lymph node metastasis for improved diagnosis.

MATERIALS AND METHODS

The subjects were 176 patients with rectal cancer who underwent preoperative MRI. The longest lymph node diameter was measured and a cut-off value for positive lymph node metastasis was established based on a receiver operating characteristic (ROC) curve. A logistic model was constructed based on MRI findings and risk factors for lymph node metastasis extracted from logistic-regression analysis. The diagnostic capabilities of MRI alone and those of the logistic model were compared using the area under the curve (AUC) of the ROC curve.

RESULTS

The cut-off value was a diameter of 5.47 mm. Diagnosis using MRI had an accuracy of 65.9%, sensitivity 73.5%, specificity 61.3%, positive predictive value (PPV) 62.9%, and negative predictive value (NPV) 72.2% [AUC: 0.6739 (95%CI: 0.6016-0.7388)]. Age (<59) (p=0.0163), pT (T3+T4) (p=0.0001), and BMI (<23.5) (p=0.0003) were extracted as independent risk factors for lymph node metastasis. Diagnosis using MRI with the logistic model had an accuracy of 75.0%, sensitivity 72.3%, specificity 77.4%, PPV 74.1%, and NPV 75.8% [AUC: 0.7853 (95%CI: 0.7098-0.8454)], showing a significantly improved diagnostic capacity using the logistic model (p=0.0002).

CONCLUSIONS

A logistic model including risk factors for lymph node metastasis can improve the accuracy of MRI diagnosis of rectal cancer.

摘要

背景

评估磁共振成像（MRI）及包含淋巴结转移风险因素的逻辑模型在改善直肠癌诊断方面的应用。

材料与方法

研究对象为176例接受术前MRI检查的直肠癌患者。测量淋巴结最长直径，并根据受试者工作特征（ROC）曲线确定阳性淋巴结转移的截断值。基于MRI结果及从逻辑回归分析中提取的淋巴结转移风险因素构建逻辑模型。使用ROC曲线下面积（AUC）比较单纯MRI及逻辑模型的诊断能力。

结果

截断值为直径5.47mm。MRI诊断的准确率为65.9%，敏感性为73.5%，特异性为61.3%，阳性预测值（PPV）为62.9%，阴性预测值（NPV）为72.2% [AUC：0.6739（95%CI：0.6016 - 0.7388）]。年龄（<59岁）（p = 0.0163）、pT（T3 + T4）（p = 0.00）及BMI（<23.5）（p = 0.0003）被提取为淋巴结转移的独立风险因素。使用MRI联合逻辑模型诊断的准确率为75.0%，敏感性为72.3%，特异性为77.4%，PPV为74.1%，NPV为75.8% [AUC：0.7853（95%CI：0.7098 - 0.8454）]，表明逻辑模型显著提高了诊断能力（p = 0.0002）。