^(18)F-FDG PET双期扫描在浅表淋巴结良恶性鉴别诊断中的价值

Differentiation of Malignant and Benign Superficial Lymph Nodes by Dual Time Point ^(18)F-FDG PET

目的评价18F-脱氧葡萄糖(FDG)正电子发射型计算机断层显像(PET)双期扫描在浅表淋巴结良恶性鉴别诊断中的价值。方法选择68例患者为研究对象,分别于注射18F-FDG后1h及2h行早期全身PET显像及局部感兴趣区延迟显像。测出每处淋巴结早期及延迟期最大标准摄取值SUVearly及SUVdelayed,并计算出每个病灶的滞留指数(RI)。采用受试者操作特性曲线(ROC)比较SUVearly、SUVdelayed及RI在浅表淋巴结良恶性鉴别诊断中的价值。结果良恶性淋巴结的SUVearly分别为3.26±1.62及8.04±5.56(P=0.000),SUVdelayed分别为3.93±2.11及9.82±6.29(P=0.000),RI分别为19.1±22.5及24.8±18.8(P=0.191)。SUVearly、SUVdelayed和RI的临界值分别为4.3、4.8及18时,对浅表淋巴结良恶性诊断的敏感性分别为71%、78%、63%,特异性分别为87%、85%、46%,准确性分别为78%、80%、57%。ROC分析显示SUVearly和SUVdelayed的诊断效能无明显差异(P=0.409),但均高于RI的诊断效能(P<0.001)。结论本研究条件下,18F-FDGPET双期扫描不能提高浅表淋巴结良恶性诊断的价值。

Objective To evaluate the value of dual time point 18^ F-fluorodeoxyglucose positron emission tomography （18^F-FDG PET） in differentiating malignant and benign superficial lymph nodes. Methods Sixty-eight patients with ninety superficial lymph nodes were examined. Whole body 18^F-FDG PET imaging was performed one hour （early） after FDG injection and repeated one hour （delayed） later but only for the interesting areas. The maximum standardized uptake value （SUVmax） was determined for each of the node on both early and delayed images （SUVearly and SUVdelayed, respectively）. Retention index （RI） was then calculated. The cutoff values of SUVearly, SUVdelayed and RI were determined by receiver operating characteristic （ROC） analyses. The efficacy of each parameter was also analyzed by ROC analyses. Results The histopathology examinations confirmed 51 malignant nodes and 39 benign nodes. The SUVearly （-↑x ±s） for benign nodes and malignant nodes were 3.26 ± 1.62 and 8.04 ±5.56, respectively （P=0. 000）. The SUVdelayed for benign nodes and malignant nodes were 3.93±2.11 and 9. 82±6.29, respectively （P=0. 000）. The RI for benign nodes and malignant nodes were 19. 1± 22.5 and 24.8± 18.8, respectively （P=0. 191）. The cutoff values of SUVearly, SUVdelayed and RI were 4.3, 4.8 and 18, respectivley. The cutoff values of SUVearly, SUVdelayed and RI produced a sensitivity of 71%, 78% and 63%, a specificity of 87%, 85% and 46%, and an accuracy of 78%, 80% and 57%, respectively. The ROC analyses illustrated that the diagnostic efficacy of SUVearly, SUVdelayed was higher than RI （P〈0. 001）. However, there was no difference in diagnostic efficacy between SUVearly and SUVdelayed （P= 0. 409）. Conclusion Dual-time point 18^F-FDG PET does differentiate benign and malignant superficial lymph nodes effectively.