Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
J Dig Dis. 2014 Apr;15(4):188-94. doi: 10.1111/1751-2980.12124.
To evaluate the performance of diffusion-weighted imaging (DWI) in the T staging of primary rectal cancer compared with T2-weighted (T2W) fast spin-echo imaging using 3.0 tesla magnetic resonance imaging (MRI).
In total, 46 consecutive patients with rectal cancer who underwent MRI examination before surgery were included in the study. The diagnostic accuracy, sensitivity and specificity of DWI and T2W imaging (T2WI) for T staging of the tumors were evaluated, and interobserver agreement between the two radiologists was calculated.
The diagnostic accuracies of DWI and T2WI for the T staging of rectal cancer were 73.9% and 71.7%, respectively. The sensitivity and specificity of DWI were 90.0% and 88.9% for diagnosing T1 tumors, 64.3% and 87.5% for T2 tumors, 77.8% and 89.3% for T3 tumors and 50.0% and 97.6% for T4 tumors, respectively; while the sensitivity and specificity of T2WI were 80.0% and 91.7% for T1 tumors, 64.3% and 78.1% for T2 tumors, 77.8% and 89.3% for T3 tumors and 50.0% and 100% for T4 tumors, respectively. There were no significant differences in the diagnostic accuracy, sensitivity or specificity between DWI and T2WI no matter what kind of T stage was concerned (P > 0.05). The interobserver agreement was 0.74 for DWI and 0.63 for T2WI.
DWI can be applied as a useful tool for evaluating the T staging of rectal cancer. The interobserver agreement obtained by using DWI is better than that obtained by using T2WI.
评估 3.0T 磁共振成像（MRI）弥散加权成像（DWI）在原发性直肠癌 T 分期中的表现，与 T2 加权（T2W）快速自旋回波成像相比。
共纳入 46 例术前接受 MRI 检查的直肠癌患者。评估 DWI 和 T2W 成像（T2WI）对肿瘤 T 分期的诊断准确性、敏感性和特异性，并计算两位放射科医生之间的观察者间一致性。
DWI 和 T2WI 对直肠癌 T 分期的诊断准确率分别为 73.9%和 71.7%。DWI 诊断 T1 肿瘤的敏感性和特异性分别为 90.0%和 88.9%，诊断 T2 肿瘤的敏感性和特异性分别为 64.3%和 87.5%，诊断 T3 肿瘤的敏感性和特异性分别为 77.8%和 89.3%，诊断 T4 肿瘤的敏感性和特异性分别为 50.0%和 97.6%；而 T2WI 诊断 T1 肿瘤的敏感性和特异性分别为 80.0%和 91.7%，诊断 T2 肿瘤的敏感性和特异性分别为 64.3%和 78.1%，诊断 T3 肿瘤的敏感性和特异性分别为 77.8%和 89.3%，诊断 T4 肿瘤的敏感性和特异性分别为 50.0%和 100%。无论哪种 T 分期，DWI 和 T2WI 的诊断准确性、敏感性或特异性均无显著差异（P>0.05）。DWI 的观察者间一致性为 0.74，T2WI 的观察者间一致性为 0.63。
DWI 可作为评估直肠癌 T 分期的有用工具。使用 DWI 获得的观察者间一致性优于使用 T2WI 获得的一致性。
