Department of Radiology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Department of Radiology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea.
Eur Radiol. 2020 Jun;30(6):3113-3124. doi: 10.1007/s00330-020-06711-1. Epub 2020 Feb 18.
To assess the added value of MRI over CT for the detection of pelvic recurrence during postoperative surveillance after rectal cancer surgery and to compare the diagnostic accuracy for pelvic recurrence achieved with abbreviated MRI (aMRI) with that of conventional enhanced MRI (cMRI).
Patients who underwent rectal cancer surgery followed by MRI in addition to the standard CT follow-up protocol were evaluated retrospectively. Two readers independently scored images from CT, cMRI, and aMRI, which consisted of T2-weighted and diffusion-weighted imaging, to rate the likelihood of recurrence. Diagnostic accuracy and ROC curves were calculated. The patients were divided into two groups for risk-adapted surveillance according to risk of recurrence: high-risk (n = 157) and low-risk (n = 169) groups.
In total, 579 MRIs from 326 patients were assessed. A total of 48 pelvic recurrences occurred in 33 patients. The AUC in cMRI, aMRI, and CT were 0.98, 0.99, and 0.84, respectively. The difference in performance between CT and cMRI or aMRI for identifying recurrence was statistically significant (p < 0.001). Both cMRI and aMRI showed superior performance compared with CT in the high-risk group (p < 0.001), but this was not the case in the low-risk group (p = 0.13). Furthermore, the diagnostic accuracy of aMRI was similar to that of cMRI.
The addition of MRI to the postoperative surveillance protocol may result in an improvement in the detection of pelvic recurrence after rectal cancer surgery. For patients at high risk of recurrence, an aMRI surveillance may be justified to improve the diagnostic yield.
• The addition of MRI to the postoperative surveillance protocol improved the diagnostic yield in patients at a high risk of recurrence. • Abbreviated non-enhanced MRI with DWI allows detection of pelvic recurrence with a diagnostic accuracy that is similar to that of contrast-enhanced MRI (AUC, 0.99 and 0.98, respectively; p = 0.12). • Abbreviated MRI that is restricted to high spatial resolution structural imaging and diffusion-weighted imaging takes less time and can be carried out without the need for injection of a contrast agent.
评估 MRI 相对于 CT 在直肠癌术后监测中对盆腔复发的检测价值，并比较缩短 MRI（aMRI）与常规增强 MRI（cMRI）检测盆腔复发的诊断准确性。
回顾性评估了接受直肠癌手术后除标准 CT 随访方案外还接受 MRI 的患者。两位读者分别对 CT、cMRI 和 aMRI 的图像进行评分，这些图像包括 T2 加权和弥散加权成像，以评估复发的可能性。计算了诊断准确性和 ROC 曲线。根据复发风险将患者分为两组进行风险适应性监测：高危组（n=157）和低危组（n=169）。
共评估了 326 名患者的 579 次 MRI。33 名患者共发生 48 例盆腔复发。cMRI、aMRI 和 CT 的 AUC 分别为 0.98、0.99 和 0.84。CT 与 cMRI 或 aMRI 之间在识别复发方面的性能差异具有统计学意义（p<0.001）。cMRI 和 aMRI 在高危组中的表现均优于 CT（p<0.001），但在低危组中并非如此（p=0.13）。此外，aMRI 的诊断准确性与 cMRI 相似。
在术后监测方案中添加 MRI 可能会提高直肠癌手术后盆腔复发的检测率。对于复发风险较高的患者，进行 aMRI 监测可能有助于提高诊断效果。
在术后监测方案中添加 MRI 可提高复发风险较高患者的诊断效果。
具有高空间分辨率结构成像和弥散加权成像限制的缩短型非增强 MRI 可检测到盆腔复发，其诊断准确性与增强 MRI 相似（AUC 分别为 0.99 和 0.98，p=0.12）。
缩短型 MRI 仅需较短的时间，且无需注射造影剂即可进行，限制为高空间分辨率结构成像和弥散加权成像。
