Department of Radiology, Affiliated Hospital of Jiangnan University, 200 Huihe Road, Wuxi, Jiangsu, China.
Department of Pathology, Affiliated Hospital of Jiangnan University, 200 Huihe Road, Wuxi, Jiangsu, China.
Eur Radiol. 2021 May;31(5):3347-3354. doi: 10.1007/s00330-020-07359-7. Epub 2020 Nov 13.
To evaluate the diagnostic value and reproducibility of T2 mapping versus apparent diffusion coefficients (ADC) for identifying malignant lymph nodes in patients with non-mucinous rectal adenocarcinoma.
High-resolution magnetic resonance imaging, diffusion-weighted imaging, and T2 mapping were performed on patients with suspected metastatic lymph nodes in the mesorectum or around the superior rectal artery with a short-axis diameter of 4-10 mm. The T2 and ADC values of pathology-confirmed metastatic versus non-metastatic lymph nodes were compared using the independent-samples t test and receiver operating characteristic curves. Intra- and inter-observer reproducibility were tested. The cutoff value for T2 relaxation time was determined.
In total, 67 lymph nodes underwent histological analysis, with 24 in the non-metastatic and 43 in the metastatic groups. Intra- and inter-observer agreements for T2 values were 0.999 and 0.998, respectively, which were higher than the ADC values of 0.924 and 0.844, respectively. The mean T2 and ADC values for metastatic lymph nodes (65 ± 7.8 ms and 1.17 ± 0.16 × 10 mm/s, respectively) were significantly lower than for benign lymph nodes(83 ± 5.7 ms and 1.29 ± 0.15 × 10 mm/s, respectively). T2 values had a higher AUC value of 0.990 than the AUC value for ADC of 0.729. With a cutoff value of 77 ms, sensitivity and specificity for T2 values were 95% and 96%, respectively.
T2 mapping had higher diagnostic efficacy and reproducibility than ADC and may be useful in differentiating metastatic from non-metastatic lymph nodes in rectal cancer.
• Mean T2 values were significantly shorter for malignant versus benign LNs in patients with non-mucinous rectal adenocarcinoma. • The diagnostic efficacy and reproducibility of T2 values were excellent and superior to ADC values.
评估 T2 映射与表观扩散系数（ADC）在识别非黏液性直肠腺癌患者中直肠系膜或直肠上动脉周围 4-10mm 短轴直径的恶性淋巴结中的诊断价值和可重复性。
对怀疑有转移的直肠系膜或直肠上动脉周围淋巴结进行高分辨率磁共振成像、扩散加权成像和 T2 映射，其短轴直径为 4-10mm。使用独立样本 t 检验和受试者工作特征曲线比较病理证实的转移性与非转移性淋巴结的 T2 值和 ADC 值。测试了内部和观察者之间的可重复性。确定 T2 弛豫时间的截止值。
共有 67 个淋巴结进行了组织学分析，其中非转移性组 24 个，转移性组 43 个。T2 值的观察者内和观察者间一致性分别为 0.999 和 0.998，均高于 ADC 值的 0.924 和 0.844。转移性淋巴结的平均 T2 和 ADC 值（分别为 65 ± 7.8ms 和 1.17 ± 0.16×10mm/s）明显低于良性淋巴结（分别为 83 ± 5.7ms 和 1.29 ± 0.15×10mm/s）。T2 值的 AUC 值为 0.990，高于 ADC 的 AUC 值 0.729。当截断值为 77ms 时，T2 值的敏感性和特异性分别为 95%和 96%。
T2 映射比 ADC 具有更高的诊断效能和可重复性，可能有助于区分直肠癌中转移性和非转移性淋巴结。
在非黏液性直肠腺癌患者中，恶性与良性淋巴结的平均 T2 值明显更短。
T2 值的诊断效能和可重复性均非常出色，优于 ADC 值。
