¹¹C-蛋氨酸和 ¹⁸F-氟代脱氧葡萄糖正电子发射断层扫描/计算机断层扫描在疑似原发性和残留/复发性脑胶质瘤患者中的评估。

¹¹C-methionine and ¹⁸F-fluorodeoxyglucose positron emission tomography/CT in the evaluation of patients with suspected primary and residual/recurrent gliomas.

机构信息

PET Center, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, China.

出版信息

Chin Med J (Engl). 2012 Jan;125(1):91-6.

Abstract

BACKGROUND

(18)F-fluorodeoxyglucose (FDG) is the most widely used radiotracer in tumor imaging, but its use for brain gliomas and recurrence is limited by the high (18)F-FDG uptake in normal brain tissue. (11)C-methionine (MET) has low uptake in the normal brain tissue, providing potential advantages over (18)F-FDG. The aim of the study was to investigate the diagnostic value of (11)C-MET compared to (18)F-FDG positron emission tomography and computed tomography (PET/CT) in patients with suspected primary and residual/recurrent gliomas.

METHODS

Eighty paired PET/CT scans using (11)C-MET and (18)F-FDG were performed on 44 newly diagnosed patients with suspected gliomas and 36 post-operative patients with suspected residual/recurrent tumors. PET/CT results were evaluated by visual and semiquantitative analysis. The sensitivity, specificity and accuracy for detection of gliomas and residual/recurrent tumors were calculated using visual analysis. Tumor to contralateral normal gray matter (T/G) ratio was calculated for semiquantitative analysis.

RESULTS

Final pathology of the 44 newly diagnosed patients included 26 gliomas (14 high-grade and 12 low-grade tumors) and 18 non-glioma benign lesions. Residual/recurrent gliomas were verified in 28 patients and excluded in 8/36 post-operative patients by subsequent histopathologic examination and/or clinical follow-up for more than six months. The sensitivity, specificity and accuracy of (11)C-MET PET/CT were 88.5%, 83.3% and 86.4% for gliomas and 96.4%, 87.5% and 94.4% for residual/recurrent gliomas, respectively. The sensitivity, specificity and accuracy of (18)F-FDG PET/CT were 50.0%, 88.9% and 65.9% for gliomas and 46.4%, 100.0% and 58.3% for residual/recurrent gliomas, respectively. (11)C-MET had a higher sensitivity than (18)F-FDG (83.3% vs. 33.3%, P = 0.031) in low-grade gliomas, but had no significant difference in sensitivity from (18)F-FDG for high-grade gliomas (92.9% vs. 64.3%, P = 0.219). (11)C-MET T/G uptake ratios in high-grade gliomas, low-grade gliomas and benign lesions were 1.94 ± 0.53, 1.78 ± 0.61 and 1.06 ± 0.34, respectively. (18)F-FDG T/G uptake ratios in high-grade gliomas, low-grade gliomas and benign lesions were 1.05 ± 0.37, 0.66 ± 0.14 and 0.63 ± 0.17, respectively.

CONCLUSIONS

(11)C-MET PET/CT is superior to (18)F-FDG PET/CT in detecting and delineating gliomas and residual/recurrent tumors, especially low-grade gliomas and residual/recurrent lesions present in gray matter, but its role in non-invasive grading of the tumors is limited.

摘要

背景

（18）F-氟代脱氧葡萄糖（FDG）是肿瘤成像中最常用的放射性示踪剂，但由于正常脑组织中（18）F-FDG 的摄取量较高，其在脑胶质瘤和复发中的应用受到限制。（11）C-蛋氨酸（MET）在正常脑组织中的摄取量较低，与（18）F-FDG 相比具有潜在优势。本研究旨在探讨（11）C-MET 与（18）F-FDG 正电子发射断层扫描和计算机断层扫描（PET/CT）在疑似原发性和残留/复发性脑胶质瘤患者中的诊断价值。

方法

对 44 例疑似脑胶质瘤的新诊断患者和 36 例疑似残留/复发性肿瘤的术后患者进行了 80 对（11）C-MET 和（18）F-FDG PET/CT 检查。通过视觉和半定量分析评估 PET/CT 结果。使用视觉分析计算检测胶质瘤和残留/复发性肿瘤的灵敏度、特异性和准确性。计算肿瘤与对侧正常灰质（T/G）比值进行半定量分析。

结果

44 例新诊断患者的最终病理结果包括 26 例胶质瘤（14 例高级别和 12 例低级别肿瘤）和 18 例非胶质瘤良性病变。通过随后的组织病理学检查和/或超过 6 个月的临床随访，在 28 例患者中证实了残留/复发性胶质瘤，并排除了 36 例术后患者中的 8 例残留/复发性胶质瘤。（11）C-MET PET/CT 对胶质瘤的灵敏度、特异性和准确性分别为 88.5%、83.3%和 86.4%，对残留/复发性胶质瘤的灵敏度、特异性和准确性分别为 96.4%、87.5%和 94.4%。（18）F-FDG PET/CT 对胶质瘤的灵敏度、特异性和准确性分别为 50.0%、88.9%和 65.9%，对残留/复发性胶质瘤的灵敏度、特异性和准确性分别为 46.4%、100.0%和 58.3%。（11）C-MET 在低级别胶质瘤中的灵敏度（83.3%比 33.3%，P = 0.031）高于（18）F-FDG，但在高级别胶质瘤中的灵敏度与（18）F-FDG 无显著差异（92.9%比 64.3%，P = 0.219）。高级别胶质瘤、低级别胶质瘤和良性病变的（11）C-MET T/G 摄取比值分别为 1.94 ± 0.53、1.78 ± 0.61 和 1.06 ± 0.34，（18）F-FDG T/G 摄取比值分别为 1.05 ± 0.37、0.66 ± 0.14 和 0.63 ± 0.17。