Lee Jai Hyuen, Park Seok Gun, Jee Keum Nahn, Park Dong Guk, Namgung Hwan, Song Il Han
Department of Nuclear Medicine, Dankook University College of Medicine, Cheonan, Korea.
Nucl Med Commun. 2010 Jun;31(6):576-82. doi: 10.1097/MNM.0b013e32833845b7.
The performance of 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography/computed tomography (FDG PET/CT) has been not established for the evaluation of recurrent colorectal cancer. The aim of this study was to evaluate the diagnostic value of FDG PET/CT in postoperative colorectal cancer patients with normal carcinoembryonic antigen (CEA) levels.
This retrospective study was conducted on 63 FDG PET/CT cases, involving postoperative colorectal cancer patients suspected of having recurrent or metastatic lesions with normal CEA levels. The diagnostic performance of FDG PET/CT was evaluated based on diverse suspected conditions, using physical examination, a conventional imaging work-up, and endoscopy. Histopathology, a clinical imaging work-up (including an FDG PET/CT examination), and determination of tumor marker levels during the follow-up served as the reference standard.
The sensitivity, specificity, and accuracy for FDG PET/CT were 95, 76.6, and 88.8% for a lesion-by-lesion analysis, and 96.3, 86.1, and 90.5% for a case-by-case analysis, respectively. Three false-negative lesions among 107 suspected recurrent findings were identified as compared with nine false-positive lesions. For radiologically suspected recurrent or metastatic conditions, FDG PET/CT diagnostic performance was superior to radiological image modalities, for both lesion-by-lesion and case-by-case analyses. On follow-up of patients with normal CEA levels, but high CA19-9 levels, the use of FDG PET/CT detected true-positive findings in 63.3% of cases.
FDG PET/CT is a valuable tool to distinguish recurrence or metachronous tumor from postoperative changes or other benign lesions in postoperative colorectal cancer patients with normal CEA levels and radiologically or clinically suspicious lesions.
2-脱氧-2-[(18)F]氟-D-葡萄糖正电子发射断层扫描/计算机断层扫描（FDG PET/CT）在复发性结直肠癌评估中的性能尚未确立。本研究旨在评估FDG PET/CT在癌胚抗原（CEA）水平正常的术后结直肠癌患者中的诊断价值。
对63例FDG PET/CT病例进行回顾性研究，这些病例涉及CEA水平正常但怀疑有复发或转移病变的术后结直肠癌患者。基于不同的疑似情况，采用体格检查、传统影像学检查和内镜检查来评估FDG PET/CT的诊断性能。组织病理学、临床影像学检查（包括FDG PET/CT检查）以及随访期间肿瘤标志物水平的测定作为参考标准。
逐病灶分析时，FDG PET/CT的敏感性、特异性和准确性分别为95%、76.6%和88.8%；逐病例分析时分别为96.3%、86.1%和90.5%。与9例假阳性病变相比，在107个疑似复发发现中有3例假阴性病变。对于放射学疑似复发或转移情况，无论是逐病灶分析还是逐病例分析，FDG PET/CT的诊断性能均优于放射学影像模式。在CEA水平正常但CA19-9水平高的患者随访中，使用FDG PET/CT在63.3%的病例中检测到真阳性结果。
对于CEA水平正常且有放射学或临床可疑病变的术后结直肠癌患者，FDG PET/CT是区分复发或异时性肿瘤与术后改变或其他良性病变的有价值工具。
