Objective: The aim of this study was to evaluate the diagnostic performance of dual-time-point fluorine-18-fluorodeoxyglucose positron emission computed tomography/computed tomography (18F-FDG PET/CT) compared to conventional early imaging for detecting colorectal liver metastases (CRLM) in colorectal cancer (CRC) patients. Methods: One hundred twenty-four consecutive CRC patients underwent dual-time-point imaging scans on a retrospective basis. Histopathological confirmation and/or clinical follow-up were accepted as the gold standard. Standard uptake values (SUV), signal-to-noise ratio (SNR), retention index (RI), tumor-to-normal liver ratio (TNR), and lesion sizes were measured for early and delayed PET scans. The diagnostic performance of early and delayed images was calculated on a per-patient basis and compared using McNemar’s test. Results: Among the 124 patients, 57 (46%) had CRLM, 6 (4.8%) had benign lesions, and 61 (49.2%) had no concerning lesions detected. Smaller CRLM lesions (<5 cm3) showed significantly higher uptake in the delayed scans relative to early imaging (p< 0.001). The SUV and TNR increased significantly in delayed imaging of all metastatic lesions (p< 0.001). The retention index of all CRLM was high (40.8%), especially for small lesions (54.8%). A total of 177 lesions in delayed images and 124 in standard early images were identified. In a per-patient analysis, delayed imaging had significantly higher sensitivity (100% vs. 87.7%) and specificity (91.0% vs. 94.0%) compared to early imaging (p-value = 0.04). Conclusions: The detection of liver lesions using dual-time-point PET/CT scan improves the sensitivity and specificity for the detection of colorectal liver metastasis.
目的：本研究旨在评估双时相氟-18-氟代脱氧葡萄糖正电子发射计算机断层扫描/计算机断层扫描（18F-FDG PET/CT）相较于常规早期成像在结直肠癌（CRC）患者中检测结直肠肝转移（CRLM）的诊断性能。方法：回顾性纳入124例连续收治的CRC患者进行双时相成像扫描。以组织病理学确认和/或临床随访作为金标准。分别测量早期与延迟PET扫描的标准摄取值（SUV）、信噪比（SNR）、滞留指数（RI）、肿瘤与正常肝脏比值（TNR）及病灶大小。基于患者个体计算早期与延迟图像的诊断效能，并采用McNemar检验进行比较。结果：在124例患者中，57例（46%）存在CRLM，6例（4.8%）为良性病变，61例（49.2%）未检出相关病灶。体积较小的CRLM病灶（<5 cm³）在延迟扫描中相较于早期成像显示摄取值显著升高（p<0.001）。所有转移灶的SUV与TNR在延迟成像中均显著增加（p<0.001）。全部CRLM的滞留指数较高（40.8%），小病灶尤为显著（54.8%）。延迟图像共检出177个病灶，标准早期图像检出124个病灶。基于患者的分析显示，延迟成像的敏感性（100% vs. 87.7%）与特异性（91.0% vs. 94.0%）均显著高于早期成像（p值=0.04）。结论：采用双时相PET/CT扫描检测肝脏病灶可提高结直肠肝转移诊断的敏感性与特异性。
肿瘤(癌症)患者之家