Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Korea.
World J Surg. 2009 Dec;33(12):2688-94. doi: 10.1007/s00268-009-0248-3.
Performing a restaging work-up with magnetic resonance imaging (MRI) and (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG PET/CT) can provide information about the effects that are related to preoperative concurrent chemoradiotherapy (CCRT). The purpose of the present study was to investigate the accuracy of MRI and (18)F-FDG PET/CT for restaging after preoperative CCRT for rectal cancer.
Between April 2005 and February 2006, 30 patients with histologically proven rectal adenocarcinoma were included in this study. Pelvic MRI and (18)F-FDG PET/CT were performed to clinically restage the tumor after CCRT. The results of the pathologic staging were correlated with those of the MRI and (18)F-FDG PET/CT after CCRT. Two patients underwent transanal endoscopic microsurgery after CCRT, and they were excluded when the N category was evaluated.
The overall accuracy of MRI for the T category was 67% (kappa = 0.422, P = 0.003), whereas overstaging and understaging occurred in 30 and 3% of the patients, respectively. For the N category, accurate staging was noted in 75% (kappa = 0.410, P = 0.030) of all the patients, whereas 14% were overstaged and 11% were understaged. The overall accuracy rates for the T and N categories with performing (18)F-FDG PET/CT were 60% (kappa = 0.372, P = 0.004) and 71% (kappa = 0.097, P = 0.549), respectively. While MRI could not predict any patient who showed a pathologic complete response, (18)F-FDG PET/CT predicted three of the four patients who showed a pathologic complete response after preoperative CCRT. Furthermore, (18)F-FDG PET/CT identified distant metastases with an accuracy rate of 97%.
For restaging patients with rectal cancer after preoperative CCRT, MRI is a useful diagnostic modality to predict both the T and N categories. (18)F-FDG PET/CT is helpful in predicting a pathologic complete response and in finding metastasis after preoperative CCRT.
使用磁共振成像（MRI）和（18）F-氟脱氧葡萄糖正电子发射断层扫描/计算机断层扫描（（18）F-FDG PET/CT）进行重新分期可提供与术前同期放化疗（CCRT）相关的效果信息。本研究的目的是研究 MRI 和（18）F-FDG PET/CT 在术前 CCRT 后对直肠癌重新分期的准确性。
2005 年 4 月至 2006 年 2 月，纳入 30 例经组织学证实的直肠腺癌患者。在 CCRT 后进行盆腔 MRI 和（18）F-FDG PET/CT 以临床重新分期肿瘤。将病理分期结果与 CCRT 后的 MRI 和（18）F-FDG PET/CT 结果相关联。2 例患者在 CCRT 后接受经肛门内镜微创手术，在评估 N 分期时将其排除在外。
MRI 对 T 分期的总体准确性为 67%（kappa=0.422，P=0.003），分别有 30%和 3%的患者出现过度分期和分期不足。对于 N 分期，所有患者的准确分期率为 75%（kappa=0.410，P=0.030），14%的患者分期过度，11%的患者分期不足。进行（18）F-FDG PET/CT 时，T 期和 N 期的总准确率分别为 60%（kappa=0.372，P=0.004）和 71%（kappa=0.097，P=0.549）。虽然 MRI 不能预测任何表现为病理完全缓解的患者，但（18）F-FDG PET/CT 预测了 4 例术前 CCRT 后表现为病理完全缓解的患者中的 3 例。此外，（18）F-FDG PET/CT 对远处转移的准确率为 97%。
对于术前 CCRT 后直肠癌患者的重新分期，MRI 是一种有用的诊断方式，可预测 T 期和 N 期。（18）F-FDG PET/CT 有助于预测病理完全缓解和发现术前 CCRT 后的转移。
