利尿后18F-FDG PET/CT延迟显像对前列腺癌的临床诊断价值

目的 探讨利尿后18F-氟脱氧葡萄糖（FDG） PET/CT延迟显像对前列腺癌（PCa）的临床诊断价值和最佳延迟显像时间。 方法 回顾性分析2009年3月至2018年12月于武装警察部队特色医学中心行18F-FDG PET/CT全身显像显示前列腺病变的235例男性患者的临床资料，其中前列腺恶性病变患者77例、前列腺良性病变患者158例，年龄50~87（69.6±13.6）岁。所有患者均行利尿前及利尿后延迟显像（1、2、3、4 h），获得利尿前、后病灶的最大标准化摄取值（SUV_max）。以利尿后SUV_max>2.5且利尿前、后SUV_max的储留指数>15%作为判断良、恶性的标准。2组间数据的比较采用独立样本t检验。 结果 前列腺恶性病变患者利尿后延迟1、2、3 h显像的SUV_max均分别高于利尿前，差异均有统计学意义（5.57±1.58对4.32±1.01、7.04±3.03对4.62±1.84、7.28±2.90对4.73±1.88，t=3.399、3.676、2.660，均P<0.05）；利尿后延迟4 h显像的SUV_max与利尿前相比，差异无统计学意义（t=1.103，P=0.286）。前列腺良性病变患者利尿后延迟1、2、3、4 h显像的SUV_max与利尿前相比，差异均无统计学意义（t=0.268~0.865，均P>0.05）。恶性病变患者利尿后延迟1、2、3 h显像的SUV_max均分别高于良性病变患者（t=2.013、3.910、3.554，均P<0.05），而2组患者利尿后延迟4 h显像的SUV_max差异无统计学意义（t=1.379，P=0.181）。恶性病变患者利尿后延迟2、3 h比延迟1 h显像的SUV_max高（t=2.220、2.400，均P<0.05）。利尿后18F-FDG PET/CT延迟1、2、3、4 h显像对前列腺癌诊断效能中，延迟2 h显像的特异度74.5%（38/51）]和准确率76.3%（61/80）]最高，而延迟3 h显像的灵敏度84.6%（11/13）]最高。 结论 PCa患者利尿后延迟显像可提高显像效果和临床诊断的效能，利尿后延迟2 h显像的诊断效果较优。

Clinical diagnostic value of 18F-FDG PET/CT delayed imaging after diuresis for prostate cancer

Objective To evaluate the clinical diagnostic value and optimum delay time of 18F-fluorodeoxyglucose (FDG) PET/CT delayed imaging after diuresis in prostate cancer (PCa). Methods The clinical data of 235 male patients with prostate diseases who underwent 18F-FDG PET/CT whole-body imaging at the Characteristic Medical Center of the Chinese People's Armed Police Force from March 2009 to December 2018, including 77 patients with malignant prostate diseases and 158 patients with benign prostate diseases were retrospectively analyzed, aged 50–87(69.6±13.6) years old. All patients underwent delayed imaging before and after diuresis(1, 2, 3, and 4 h) to obtain the maximum standardized uptake value (SUV_max) of lesions before and after diuresis. SUV_max>2.5 after diuresis and a retention index>15% of SUV_max before and after diuresis were used as the criteria to judge as benign or malignant. Independent sample t-test was used to compare the data between the two groups in accordance with normal distribution. Results The SUV_max of patients with prostate malignant lesions delayed 1, 2, and 3 h imaging after diuresis was significantly higher than that before diuresis (5.57±1.58 vs. 4.32±1.01, 7.04±3.03 vs. 4.62±1.84, 7.28±2.90 vs. 4.73±1.8; t=3.399, 3.676, 2.660; all P<0.05). No significant difference in SUV_max existed between prediuretic and delayed 4 h imaging after diuresis (t=1.103, P=0.286). In patients with benign prostate diseases, no significant difference existed in SUV_max delayed 1, 2, 3, and 4 h imaging after diuresis compared with that before diuresis (t=0.268–0.865, all P>0.05). The SUV_max of malignant lesions delayed 1, 2, and 3 h imaging after diuresis was higher than that in benign lesions (t=2.013, 3.910, 3.554; all P<0.05). However, no significant difference in SUV_max delayed 4 h imaging existed between the two groups (t=1.379, P=0.181). The SUV_max of patients with malignant lesions delayed 2 and 3 h was higher than that for diuretic imaging delayed 1 h (t=2.220, 2.400; both P<0.05). Diagnostic efficiency of 18F-FDG PET/CT delayed imaging (1, 2, 3, and 4 h) after diuresis in Pca, the specificity (74.5%, 38/51) and accuracy (76.3%, 61/80) of 2 h delayed imaging were the highest, while the sensitivity (84.6%, 11/13) of 3 h delayed imaging was the highest. Conclusions Delayed imaging after diuresis can improve the imaging effect and clinical diagnostic efficacy of PCa patients. The diagnostic effect of delayed imaging after diuresis for 2 h was better.