Tatsumoto Shota, Itoh Takahiro, Takahama Junko, Marugami Nagaaki, Minamiguchi Kiyoyuki, Tanaka Toshihiro, Koyama Fumikazu, Morita Kohei, Kichikawa Kimihiko
Department of Radiology, Nara Medical University, 840 Shijo-cho, Kashihara, 634-8522, Japan.
Department of Surgery, Nara Medical University, 840 Shijo-cho, Kashihara, 634-8522, Japan.
Jpn J Radiol. 2020 Jun;38(6):539-546. doi: 10.1007/s11604-020-00933-5. Epub 2020 Feb 25.
To retrospectively assess the accuracy of magnetic resonance imaging (MRI) in predicting dentate line invasion in low rectal cancer.
Eighty-one patients with primary rectal cancer were assessed by dynamic contrast-enhanced MRI. The location of the dentate line was assessed on MRI in 27 patients with upper-mid rectal cancer. Two observers independently evaluated the distance between the distal tumor edge and the MRI-defined dentate line in 54 patients with low rectal cancer, and the imaging and histological findings were compared.
The MRI-defined dentate line was 24.0 ± 3.8 mm above the anal verge in patients with upper-mid rectal cancer. The dentate line invasion status agreed with the histological findings in 49/54 (91%) patients (κ = 0.72 [95% CI 0.50-0.95]) for observer 1, and in 51/54 (94%) patients (κ = 0.83 [0.65-1.00]) for observer 2 in patients with low rectal cancer. Interobserver agreement was good (κ = 0.83 [0.65-1.00]). The MRI-derived distance between the distal tumor edge and the dentate line had significant correlation with the histological distance (r = 0.86 for reader 1 and 0.75 for observer 2).
MRI demonstrates high accuracy in predicting dentate line invasion in low rectal cancer.
回顾性评估磁共振成像（MRI）预测低位直肠癌齿状线侵犯的准确性。
对81例原发性直肠癌患者进行动态对比增强MRI评估。对27例中高位直肠癌患者在MRI上评估齿状线的位置。两名观察者独立评估54例低位直肠癌患者肿瘤远端边缘与MRI定义的齿状线之间的距离，并比较影像学和组织学结果。
中高位直肠癌患者MRI定义的齿状线距肛缘24.0±3.8mm。在低位直肠癌患者中，观察者1的49/54（91%）例患者（κ=0.72[95%CI 0.50 - 0.95]）和观察者2的51/54（94%）例患者（κ=0.83[0.65 - 1.00]）的齿状线侵犯情况与组织学结果一致。观察者间一致性良好（κ=0.83[0.65 - 1.00]）。MRI得出的肿瘤远端边缘与齿状线之间的距离与组织学距离有显著相关性（观察者1的r=0.86，观察者2的r=0.75）。
MRI在预测低位直肠癌齿状线侵犯方面显示出高准确性。
