18F-FLT PET/CT与18F-FDG PET/CT在鼻咽癌诊断和分期中的应用比较

目的 通过与18F-FDG PET/CT显像对比,探讨18 F-FLT PET/CT检测鼻咽癌原发灶和颈部淋巴结转移灶的可行性.方法 12例初治且经病理确诊的鼻咽癌患者(年龄22～62岁)自愿进入该前瞻性临床研究.每位患者先行18F-FDG PET/CT检查,次日行18F-FLF PET/CT检查.至少有2位核医学科和放射科医师阅片,比较18F-FDG PET/CT和18F-FLT PET/CT图像,采用ROI技术计算鼻咽肿瘤、颈部淋巴结转移灶、正常组织对18F-FDG、18F-FLT的SUVmax、SUVmean和MTV.采用非参数Wilcoxon秩和检验比较组间摄取和MTV差异.结果 12例鼻咽癌患者病灶均明显摄取18F-FLT.18F-FLT PET/CT和18F-FDG PET/CT均可准确诊断该组病例,二者对原发灶和淋巴结转移灶的检测结果无明显差别.鼻咽癌病灶的18F-FDG和18F-FLT SUVmax分别为10.7±5.8和6.0±2.4,SUVmean分别为5.8±3.0和3.6±1.5；SUVmax和SUVmean组间差异均有统计学意义(Z=-2.589和-2.353,P均＜0.05),而 MTV在18F-FDG和8F-FLT PET/CT 2种显像方法之问的差异无统计学意义(15.9±9.2和18.1±11.1;Z=-0.786,P＞0.05).6例有颈部淋巴结转移灶患者的SUVmax、SUVmean和MTV在2种显像方法间差异均无统计学意义(8.5±6.2比6.4±2.5、5.3±4.2比3.8±1.4、6.5 ±4.8比6.0±4.4;Z=-0.734、-0.734和-0.674,P均＞0.05).18F-FLT在颞叶摄取(SUVmax 0.7±0.3)明显低于18F-FDG(SUVmax 8.3±2.7;Z=-3.062,P＜0.01),其对于原发灶颅内浸润显示较18F-FDG更清晰.结论 18F-FLT PET/CT在鼻咽癌原发灶和淋巴结转移灶的诊断效能与18F-FDG PET/CT相当,对于显示原发灶的颅底附近侵犯更有利,其临床应用值得进一步研究.

A comparative study of ^18F-FLT PET/CT and ^18F-FDG PET/CT in patients with nasopharyngeal carcinoma

Objective To investigate the value of ^18 F-FLT compared to ^18 F-FDG in PET/CT diag- nosis of nasopharyngeal carcinoma （NPC）. Methods Twelve newly biopsy-proven NPC patients （age range： 22 -62 years） were prospectively enrolled into this study after obtaining patient consent. They un- derwent ^18F-FDG FET/CT first, followed by ^18F-FLT PET/CT on the consecutive day before treatment. ROIs were drawn on the primary tumor, involved lymph nodes and normal tissues. Wilcoxon rank sum test was used to compare the uptake differences between ^18F-FLT and ^18F-FDG for both the primary tumor and metastatic lymph nodes. Results All 12 patients showed increased uptake of ^18F-FLT by the primary tumor and metastatic lymph nodes, which were consistent with the findings by ^18F-FDG PET/CT. The SUVmax and SUV of ISF-FLT in the primary NPC （SUVmax 6. 0 ±2. 4, SUV 3.6 ± 1.5） were lower than those of ^18 F-FDG （ SUVmax 10.7 ± 5.8, SUVmcan 5.8 ± 3.0 ;Z = - 2. 589 and - 2. 353, both P 〈 0.05）. However,the MTV on ^18F-FDG and ^18F-FLT PET/CT showed no significant difference （15.9 ±9.2 vs 18.1 ±11.1, Z= -0.786, P 〉 0.05）. The SUV SUV and MTV of the metastatic cervical lymph nodes in 6 patients showed no significant difference between the 2 tracers （8.5 ± 6.2 vs 6.4 ± 2.5, 5.3 ±4.2 vs 3.8 ± 1.4, 6.5 ± 4.8 vs 6.0 ± 4.4 ; Z = - 0.734, - 0.734, - 0.674, respectively, all P 〉 0.05）. The ^18F-FLT up- take in the normal temporal lobe （SUVmax 0. 7 ± 0. 3 ） was significantly lower than that of ^18F-FDG（ SUVmax 8. 3 ±2. 7, Z = -3. 062, P 〈 0. 01 ）. The skull base involvement by NPC could be better delineated on ^18F-FLT PET/CT. Conclusions ^18F-FLT PET/CT has comparable diagnostic efficacy for primary NPC and metastatic cervical lymph nodes to ^18 F-FDG PET/CT. It might he better than ^18F-FDG for the evaluation of skull base involvement in NPC patients.