Kitajima Kazuhiro, Nakamoto Yuji, Okizuka Hiromi, Onishi Yumiko, Senda Michio, Suganuma Narufumi, Sugimura Kazuro
Department of Radiology, Dokkyo University School of Medicine, 880 Kita-kobayashi, Mibu, Shimotuga-gun, Tochigi 321-0293, Japan.
Ann Nucl Med. 2008 Aug;22(7):595-602. doi: 10.1007/s12149-008-0145-0. Epub 2008 Aug 29.
Positron emission tomography (PET) using (18)F-fluoro-2-deoxy-D -glucose (FDG) has a limitation in detecting cerebral metastases; however, the feasibility of detection by inline PET/computed tomography (CT) system remains unknown. We evaluated the accuracy of FDG-PET/CT of body imaging protocol for the detection of cerebral metastases when compared with PET alone and CT alone.
Fifty patients underwent whole-body FDG-PET/CT scanning including the brain and contrast enhanced brain MR (magnetic resonance) scan. PET-only, CT-only, and the fused images were interpreted, and the confidence of presence of cerebral metastases was recorded using a five-point grading scale. Area under the receiver-operating characteristic (ROC) curve (Az) was calculated. Differences among the three modalities were tested with the Cochran-Q test, followed by multiple comparisons using the McNemar test with Bonferroni adjustment.
Magnetic resonance imaging revealed 70 cerebral metastatic lesions in 20 patients. Patient-based analysis showed that the sensitivity, specificity, accuracy, and Az of PET-alone interpretation were 45%, 80%, 66%, and 0.6025, respectively, those of CT-alone interpretation were 50%, 97%, 78%, and 0.7158, respectively, and those of fused-image interpretation were 50%, 93%, 76%, and 0.7242, respectively. ROC analysis revealed significant differences among the three interpretation methods (P = 0.0238) and between PET and PET/CT (P = 0.0129). The sensitivity of PET, CT, and fused-image interpretation for detecting 70 lesions was 13%, 20%, and 20%, respectively.
Even with an integrated PET/CT scanner of body imaging protocol, the sensitivity of cerebral metastases remained unsatisfactory. To assess intracranial lesions, MR scanning should still be considered.
使用（18）F - 氟 - 2 - 脱氧 - D - 葡萄糖（FDG）的正电子发射断层扫描（PET）在检测脑转移瘤方面存在局限性；然而，在线PET/计算机断层扫描（CT）系统检测的可行性仍不明确。我们评估了全身成像方案的FDG - PET/CT在检测脑转移瘤时与单独PET和单独CT相比的准确性。
50例患者接受了包括脑部的全身FDG - PET/CT扫描以及对比增强脑磁共振（MR）扫描。对仅PET、仅CT和融合图像进行解读，并使用五点分级量表记录脑转移瘤存在的置信度。计算受试者操作特征（ROC）曲线下面积（Az）。三种模式之间的差异用 Cochr an - Q检验进行检验，随后使用带有Bonferroni校正的McNemar检验进行多重比较。
磁共振成像显示20例患者中有70个脑转移瘤病灶。基于患者的分析表明，单独PET解读的敏感性、特异性、准确性和Az分别为45%、80%、66%和0.6025，单独CT解读的分别为50%、97%、78%和0.7158，融合图像解读的分别为50%、93%、76%和0.7242。ROC分析显示三种解读方法之间存在显著差异（P = 0.0238），PET与PET/CT之间也存在显著差异（P = 0.0129）。PET、CT和融合图像解读检测70个病灶的敏感性分别为13%、20%和20%。
即使使用全身成像方案的集成PET/CT扫描仪，脑转移瘤的敏感性仍不令人满意。为评估颅内病变，仍应考虑进行MR扫描。
