^(68)Ga-PSMA-11 PET/CT在初诊前列腺癌患者中的应用价值

Application value of ^(68)Ga-PSMA-11 PET/CT in newly diagnosed prostatic cancer patients

目的探究^(68)Ga-前列腺特异膜抗原(PSMA)-11 PET/CT显像在不同危险度分层的初诊前列腺癌患者中的价值,以及相较于传统影像对转移灶的检出表现。方法回顾性分析2019年6月至2020年7月于复旦大学附属肿瘤医院行^(68)Ga-PSMA-11 PET/CT显像的60例初诊前列腺癌患者(年龄44~88岁,中位年龄69岁)的临床及影像数据。用Spearman秩相关分析探讨原发灶SUV_(max)与前列腺特异抗原(PSA)、Gleason评分(GS)的相关性。根据D′Amico前列腺癌危险因素分类方法对患者进行分层(PSA>20μg/L与≤20μg/L,GS>7分与≤7分),用χ^(2)检验评估PET/CT对不同分层患者转移灶的检出率,采用Mann-Whitney U检验分析病灶SUV_(max)的差异。根据PSA和GS将患者分为不同风险组(均小于分层界值为低风险,均大于界值为高风险,余为中风险),对比传统影像学方法(骨显像、CT或MRI),用Fisher确切概率法评价^(68)Ga-PSMA-11 PET/CT对转移灶的检出能力以及对患者分期的改变情况。结果^(68)Ga-PSMA-11在60例患者原发灶中呈不同程度的高摄取,SUV_(max)与GS、PSA呈正相关(rs值:0.42、0.38,P值:0.001、0.002)。^(68)Ga-PSMA-11 PET/CT对PSA>20μg/L组淋巴结及骨转移灶的检出率分别为11/18和13/18,高于PSA≤20μg/L组的28.57%(12/42)和35.71%(15/42)(χ^(2)值:6.56、7.56,P值:0.010、0.006),但病灶SUV_(max)差异均无统计学意义(z值:-1.04、-0.96;P值:0.299、0.337);在GS>7分组与GS≤7分组中,上述2类病灶的检出率差异也有统计学意义[54.05%(20/37)与13.04%(3/23),59.46%(22/37)与26.09%(6/23);χ^(2)值:10.09、8.19;P值:0.001、0.004],骨转移灶的SUV_(max)存在差异(z=-2.02,P=0.044)。在高风险组,^(68)Ga-PSMA-11 PET/CT对转移灶的检出率明显高于传统影像学方法(16/17与10/17;P=0.039),改变了25.0%(15/60)的患者的分期。结论PSA和GS影响^(68)Ga-PSMA-11 PET/CT对转移灶的检出率;在危险度分层为高风险时,^(68)Ga-PSMA-11 PET/CT对转移灶的检出率优于传统影像学方法;当患者PSA>20μg/L且GS>7分时,推荐行^(68)Ga-PSMA-11 PET/CT显像进行准确分期。

Objective To explore the value of ^(68)Ga-prostate specific membrane antigen(PSMA)-11 PET/CT in newly diagnosed prostate cancer patients with different risk stratifications,and to compare the performance of this modality with conventional imaging in detecting metastases.Methods From June 2019 to July 2020,the clinical and imaging data of 60 patients(age range:44-88 years,median age 69 years)who underwent ^(68)Ga-PSMA-11 PET/CT imaging in Fudan University Shanghai Cancer Center were retrospectively analyzed.Spearman rank correlation analysis was used to explore the correlation of SUV_(max) in primary foci with prostate specific antigen(PSA)and Gleason score(GS).Based on the D′Amico risk stratification(PSA>20μg/L and≤20μg/L,GS>7 and≤7),the detection rates of ^(68)Ga-PSMA-11 PET/CT for metastases were evaluated byχ^(2) test,and the differences of SUV_(max) were analyzed by Mann-Whitney U test.Patients were divided into high-risk(PSA>20μg/L and GS>7),medium-risk(PSA>20μg/L and GS≤7,or PSA≤20μg/L and GS>7),and low-risk(PSA<20μg/L and GS<7)groups according to PSA levels and GS.Compared with conventional imaging(bone imaging,CT or MRI),the ability of ^(68)Ga-PSMA-11 PET/CT to detect metastatic tumors,and the utility to change the prostate cancer stage were evaluated by Fisher′s exact test.Results High uptake of ^(68)Ga-PSMA-11 was observed in primary lesions of 60 patients,and SUV_(max) was positively correlated with GS or PSA(rs values:0.42,0.38;P values:0.001,0.002).The detection rates of lymph node and bone metastases in the group with PSA>20μg/L were 11/18 and 13/18,respectively,which were higher than those in the group with PSA≤20μg/L(28.57%(12/42)and 35.71%(15/42);χ^(2) values:6.56,7.56,P values:0.010,0.006.However,there was no statistical significance in the SUV_(max) of these lesions(z values:-1.04,-0.96;P values:0.299,0.337).There was a statistical difference in the detection rates of lymph node and bone metastases between the group with GS>7 and the group with GS≤7(lymph node:54.05%(20/37)vs 13.04%(3/23),χ^(2)=10.09,P=0.001;bone metastases:59.46%(22/37)vs 26.09%(6/23),χ^(2)=8.19,P=0.004),as well as the SUV_(max) of bone metastases(z=-2.02,P=0.044).In the high-risk group,^(68)Ga-PSMA-11 PET/CT had the higher detection rate of metastases than conventional imaging(16/17 vs 10/17;P=0.039)and it changed 25.0%(15/60)of the patients′staging.Conclusions PSA and GS affect the detection rate of ^(68)Ga-PSMA-11 PET/CT.In patients with high-risk prostate cancer,^(68)Ga-PSMA-11 PET/CT is superior to conventional imaging in detecting metastases.When PSA>20μg/L and GS>7,it is better to use ^(68)Ga-PSMA-11 PET/CT in prostate cancer staging.