^(68)Ga-PSMA联合18F-FDG PET/CT显像在转移性前列腺癌患者中的应用探讨

Clinical Value of Dual Tracer PET Imaging With^(68)Ga-PSMA and^(18)F-FDG in Patients With Metastatic Prostate Cancer

目的本研究回顾性收集进行^(68)镓(^(68)Ga)-前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)和18氟(^(18)F)-代脱氧葡萄糖(flurodeoxyglucose,FDG)正电子发射计算机断层成像(PET/CT)显像的转移性前列腺癌(metastatic PCa,mPCa),分析双示踪剂摄取模式,影响病灶摄取^(18)F-FDG的临床病理学参数及影响前列腺特异性抗原(prostate specific antigen,PSA)-无进展生存期(progression-free survival,PFS)的预后分析。方法回顾性纳入2021年9月–2024年1月间于我院行^(68)Ga-PSMA及^(18)F-FDG PET/CT双示踪剂显像的41例mPCa。除外1例PSMA、FDG双阴性摄取,基于是否存在FDG阳性病灶,将剩余40例分为两组:Group A(PSMA、FDG双阳性组和FDG单阳性组,33例);Group B(PSMA单阳性组,7例)。比较Group A和Group B组间临床病理学特点。通过Kaplan-Meier法分析不同参数与PSA-PFS的关系。结果26例(63.4%)患者为转移性去势抵抗性PCa(metastatic castration-resistant PCa,mCRPC),Gleason评分8~9分38例(92.7%),远处转移以骨骼转移(36例,87.8%)为主。骨骼及远处淋巴结转移灶多表现为PSMA、FDG双阳性摄取模式[85.7%(24/28),81.8%(9/11)];在脏器转移灶中,37.5%(3/8)存在FDG单阳性的摄取模式。Group A血清PSA水平高于Group B(P=0.013)。13例特殊病理类型(导管内癌和神经内分泌分化)患者均在Group A。41例患者中,16例患者失访。25例完成随访的患者中9例患者发生PSA进展,PSA中位值为104 ng/mL;16例患者无PSA进展,PSA中位值为0.34 ng/mL,两组间PSA中位值差异有统计学意义(P<0.001)。Kaplan-Meier生存分析显示特殊病理类型中位PSA-PFS(7个月)短于经典型PCa(16个月),两组间差异有统计学意义(P=0.043);Group A中位PSA-PFS为30个月,Group B仍有超过一半的个体尚未发生PSA进展,中位PSA-PFS尚未达到(P=0.645)。结论mPCa多表现为^(68)Ga-PSMA和^(18)F-FDG双示踪剂摄取,血清PSA水平是预测病灶FDG阳性的可靠指标。存在导管内癌及神经内分泌分化的mPCa病灶易表现为FDG阳性且出现PSA进展。

Objective In this study,we retrospectively analyzed the imaging characteristics of dual-tracer ^(68)Ga-prostate specific membrane antigen(PSMA)and^(18)F-flurodeoxyglucose(FDG)positron emission tomography(PET)/computed tomography(CT)in metastatic prostate cancer(mPCa)patients.We analyzed the uptake modes of the dual tracers,explored clinical pathological parameters affecting the^(18)F-FDG uptake in the lesions,and evaluated their prognostic implications for prostate specific antigen progression-free survival(PSA-PFS).Methods A total of 41 mPCa patients who underwent dual-tracer PET/CT(^(68)Ga-PSMA and^(18)F-FDG)scans between September 2021 and January 2024 were retrospectively enrolled.One patient had negative uptake of both PSMA and FDG.According to the uptake patterns of the 2 tracers,the other patients,40 in total,were categorized in 2 groups,including group A consisting of 33 cases who showed PSMA and FDG dual and those who showed FDG only avidity,and group B consisting of 7 cases who showed PSMA avidity only.Comparative analyses of clinical pathological characteristics between group A and group B were conducted.The relationship between various parameters and PSA-PFS was analyzed by the Kaplan-Meier method.Results A total of 26 patients(63.4%)were diagnosed with metastatic castration-resistant prostate cancer(mCRPC),and 38 cases(92.7%)had a Gleason score of 8-9.Bone metastasis,the predominant type of distant metastasis,occurred in 36 cases(87.8%).The skeletal and distant lymph node metastases mostly showed a dual positive uptake pattern for both PSMA and FDG(85.7%[24/28]and 81.8%[9/11]).37.5%(3/8)of the metastases to organs showed FDG only positive uptake pattern.The serum levels of prostate specific antigen(PSA)in group A were significantly higher than those in group B(P=0.013).A total of 13 patients of special pathological classification(intraductal carcinoma and neuroendocrine differentiation)were all found to be in group A.Among the 41 cases,16 were lost to follow-up.Of the 25 patients who completed follow-up,9 patients,with a median PSA value of 104 ng/mL,experienced PSA progression,while the 16 other patients,with a median PSA of 0.34 ng/mL,did not incur any PSA progression.There was significant difference in the median PSA between patients showing PSA progression and those who did not show PSA progression(P<0.001).Kaplan-Meier survival analysis revealed that the median PSA-PFS of patients of specific pathological classifications was 7 months,which was shorter than the 16 months of the patients with typical prostate cancer,with the difference between the two groups being statistically meaningful(P=0.043).The median PSA-PFS for group A was 30 months.With more than half of the patients in the group not experiencing any PSA progression,group B did not reach the median PSA-PFS(P=0.645).Conclusion Dual-tracer PET/CT imaging with ^(68)Ga-PSMA and ^(18)F-FDG commonly exhibits avidity for both tracers in mPCa.Serum PSA level is a reliable biomarker for predicting FDG-positive lesions.mPCa presented with intraductal carcinoma and neuroendocrine differentiation tends to exhibit FDG avidity and is more susceptible to PSA progression.