Low R N, McCue M, Barone R, Saleh F, Song T
Department of Diagnostic Radiology, Sharp and Children's MRI Center, Sharp Memorial Hospital, 7901 Frost Street, San Diego, CA 92123, USA.
Abdom Imaging. 2003 Nov-Dec;28(6):784-93. doi: 10.1007/s00261-003-0032-z.
We retrospectively evaluated the accuracy of magnetic resonance (MR) imaging in staging colorectal cancer and assessing local tumor extent, nodal involvement, and distant abdominal and pelvic metastases.
Forty-eight patients with primary colorectal carcinoma were referred for presurgical abdominal and pelvic MR imaging. MR imaging included T1-weighted, fat-suppressed T2-weighted, and fat-suppressed gadolinium-enhanced spin gradient-echo imaging. The prospective interpretations of the MR examinations were reviewed. MR depiction of local tumor extent, nodal involvement, and distant metastases at 18 anatomic locations was noted and compared with subsequent surgical and histopathologic findings.
Overall TNM MR staging agreed with surgical and pathologic staging in 41 (85%) of 48 patients, including 21 (78%) of 27 colon cancers and 20 (95%) of 21 rectal cancers. For depth of tumor penetration, which was evaluable in 44 patients, MR imaging agreed with pathologic results in 38 (86%) of 44 patients, including 22 (88%) of 25 colon cancers and 16 (84%) of 19 rectal cancers. In 42 (95%) of 44 patients, MR images correctly distinguished tumor confined to the bowel wall (T0, T1, and T2) from tumor with transmural tumor extension (T3 and T4). Regional nodal metastases were depicted in 15 of 22 patients (sensitivity, 68%; accuracy, 83%). Nodal metastases were better depicted for rectal cancer in eight of nine patients, compared with colon cancer in seven of 13 patients. Distant metastases were correctly depicted on MR imaging in 13 of 14 patients (sensitivity, 93%; accuracy, 98%). In the site-by-site analysis, MR imaging prospectively depicted 66 of 77 sites of surgically confirmed metastatic tumor in the abdomen and pelvis (sensitivity, 86%; specificity, 99%; accuracy, 98%).
MR imaging using currently available techniques can effectively image local tumor extent and distant metastases in patients with colorectal carcinoma. Especially for colon cancer, incomplete depiction of nodal metastases in normal-size lymph nodes remains a limitation of cross-sectional imaging studies.
我们回顾性评估了磁共振（MR）成像在结直肠癌分期以及评估局部肿瘤范围、淋巴结受累情况和腹部及盆腔远处转移方面的准确性。
48例原发性结直肠癌患者在术前接受了腹部和盆腔MR成像检查。MR成像包括T1加权、脂肪抑制T2加权和脂肪抑制钆增强自旋梯度回波成像。对MR检查的前瞻性解读进行了回顾。记录了MR对18个解剖部位的局部肿瘤范围、淋巴结受累情况和远处转移的显示，并与随后的手术和组织病理学结果进行比较。
48例患者中，41例（85%）的总体TNM MR分期与手术和病理分期一致，其中27例结肠癌中有21例（78%），21例直肠癌中有20例（95%）。对于44例可评估肿瘤浸润深度的患者，MR成像与病理结果在44例患者中的38例（86%）一致，其中25例结肠癌中有22例（88%），1例直肠癌中有16例（84%）。44例患者中的42例（95%），MR图像能够正确区分局限于肠壁的肿瘤（T0、T1和T2）与有透壁肿瘤扩展的肿瘤（T3和T4）。22例患者中有15例显示区域淋巴结转移（敏感性为68%；准确性为83%）。9例直肠癌患者中有8例的淋巴结转移显示优于13例结肠癌患者中的7例。14例患者中有13例在MR成像上正确显示了远处转移（敏感性为93%；准确性为98%）。在逐部位分析中，MR成像前瞻性地显示了腹部和盆腔77个手术证实的转移瘤部位中的66个（敏感性为86%；特异性为99%；准确性为98%）。
使用现有技术的MR成像能够有效地显示结直肠癌患者的局部肿瘤范围和远处转移。特别是对于结肠癌，正常大小淋巴结中淋巴结转移的显示不完整仍然是横断面成像研究的一个局限性。
