Department of Radiology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, 1630 Dongfang Road, Shanghai 200127, China.
Acad Radiol. 2013 Aug;20(8):939-46. doi: 10.1016/j.acra.2013.02.012. Epub 2013 Jun 5.
To prospectively assess the incremental value of diffusion-weighted imaging (DWI) combined with T2-weighted images (T2WI) in determining the T stage of bladder cancer by using pathologic findings as the reference standard.
This study is approved by the institutional review board; informed consent was waived. The study includes 362 patients (age range, 48-87 years; mean, 71 years) who underwent 3.0-T magnetic resonance imaging and histologic examination. Three observers with varying experience levels reviewed the T2WI data alone, DWI data alone, and combined T2WI and DWI data. Sensitivity, specificity, accuracy, and area under curve (AUC) were determined with the Z test after adjusting for data clustering.
For differentiating Tis to T1 tumors from T2 to T4 tumors, the AUCs for T2WI and DWI (0.97 for observer 1 and 0.96 for observer 2) were greater than those for the DWI alone (0.92 for observer 1 and 0.90 for observer 2) (P < .05). Observer 3 had similar AUCs for T2WI and DWI compared to DWI alone. The accuracy of T2WI and DWI (observer 1, 98%; observer 2, 96%; observer 3, 92%) was greater than that of DWI alone (observer 1, 92%; observer 2, 90%; observer 3, 87%) for all observers (P < .05). The specificity of T2WI and DWI (observer 1, 100%; observer 2, 98%; observer 3, 93%) was greater than that of DWI alone (observer 1, 92%; observer 2, 90%; observer 3, 87%) for all observers (P < .05). Sensitivity was not improved even when T2WI and DWI were used. For differentiating Tis to T2 Tumors from T3 to T4 Tumors, the overall accuracy, specificity, and AUC for diagnosing T2 or higher stages were not significantly improved by combiningT2WI and DWI.
T2WI combined with DWI can be a reliable sequence for preoperative evaluation of T stage urinary bladder cancer. It is particularly more useful in differentiating T1 or lower tumors from T2 or higher tumors compared to DWI alone.
前瞻性评估扩散加权成像（DWI）联合 T2 加权成像（T2WI）在以病理结果为参考标准的情况下，对膀胱癌 T 分期的附加价值。
本研究获得机构审查委员会批准，且豁免了患者知情同意。研究共纳入 362 例患者（年龄 48-87 岁，平均 71 岁），所有患者均接受 3.0T 磁共振成像和组织学检查。3 位具有不同经验水平的观察者分别单独评估 T2WI 数据、DWI 数据和 T2WI 与 DWI 联合数据。采用 Z 检验，在调整数据聚类后，确定敏感度、特异度、准确度和曲线下面积（AUC）。
对于区分Tis 期至 T1 期肿瘤与 T2 期至 T4 期肿瘤，T2WI 和 DWI 的 AUC（观察者 1 为 0.97，观察者 2 为 0.96）大于 DWI 单独的 AUC（观察者 1 为 0.92，观察者 2 为 0.90）（P＜0.05）。观察者 3 比较 T2WI 和 DWI 与 DWI 单独的 AUC 相似。T2WI 和 DWI（观察者 1 为 98%，观察者 2 为 96%，观察者 3 为 92%）的准确度大于 DWI 单独的准确度（观察者 1 为 92%，观察者 2 为 90%，观察者 3 为 87%）（所有观察者 P＜0.05）。T2WI 和 DWI（观察者 1 为 100%，观察者 2 为 98%，观察者 3 为 93%）的特异度大于 DWI 单独的特异度（观察者 1 为 92%，观察者 2 为 90%，观察者 3 为 87%）（所有观察者 P＜0.05）。即使联合 T2WI 和 DWI，敏感度也没有提高。对于区分Tis 期至 T2 期肿瘤与 T3 期至 T4 期肿瘤，T2WI 和 DWI 联合用于术前评估 T 分期时，对诊断 T2 期或更高分期的总体准确性、特异性和 AUC 没有显著改善。
T2WI 联合 DWI 可作为膀胱癌术前评估 T 分期的可靠序列。与 DWI 单独相比，T2WI 联合 DWI 尤其更有助于区分 T1 期或更低期肿瘤与 T2 期或更高期肿瘤。
