Alpha-fetoprotein and 18F-FDG standard uptake value predict tumor recurrence after liver transplantation for hepatocellular carcinoma with portal vein tumor thrombosis:Preliminary experience

Background:Portal vein tumor thrombosis(PVTT)is regarded as a contraindication for liver transplantation(LT)in hepatocellular carcinoma(HCC).However,some of these patients may have a favorable prognosis after LT.In this study,we evaluated the biological behavior of HCC with PVTT using tumor biomarker(alpha-fetoprotein,AFP)and 18 F-FDG positron emission tomography(tumor standard uptake value)to identify a subset of patients who may be suitable for LT.Methods:Seventy-five HCC-PVTT liver recipients transplanted during February 2016 and June 2018 were analyzed.Different pre-transplant prognostic factors were identified by univariate and multivariate analyses.PVTT status was identified following Vp classification(Vp1-Vp4).Results:Three-year recurrence-free survival and overall survival rates were 40%and 65.4%in Vp2-Vp3 PVTT patients,21.4%and 30.6%in Vp4 PVTT patients(P<0.05).Total tumor diameter>8 cm,pretransplant AFP level>1000 ng/m L and intrahepatic tumor maximal standard uptake value(SUVmaxtumor>5)were independent risk factors for HCC recurrence and overall survival after LT in Vp2-3 PVTT patients.Low risk patients were defined as total tumor diameter≤8 cm;or if total tumor diameter more than 8 cm,with both pre-transplant AFP level less than 1000 ng/m L and intrahepatic tumor SUVmax less than 5,simultaneously.Twenty-two Vp2-3 PVTT HCC patients(46.8%)were identified as low risk patients,and their 3-year recurrence-free and overall survival rates were 67.6%and 95.2%,respectively.Conclusions:Patients with segmental or lobar PVTT and biologically favorable tumors defined by AFP and 18 F-FDG SUVmax might be suitable for LT.

Prognostic Value of Semi-Quantitative 18F-FDG PET/CT Parameters in Hodgkin’s Lymphoma

Objective:To assess the prognostic value of maximum standardized uptake value(SUVmax),metabolic tumor volume(MTV),and total lesion glycolysis(TLG)determined by 18F-fluorodeoxyglucose positron emission tomography-computed tomography(18F-FDG PET/CT)imaging in Hodgkin’s lymphoma patients.Methods:A total of 148 Hodgkin’s lymphoma patients diagnosed with lymph node biopsy from October 2014 to October 2015 were retrospectively analyzed followed by categorizing into good(125 cases)and poor(23 cases)prognosis groups.The chi-squared test was used to analyze the clinicopathological characteristics of Hodgkin’s lymphoma patients with the semi-quantitative 18F-FDG PET/CT parameters;the Spearman method was used to analyze the correlation between the semi-quantitative parameters and clinicopathological features of Hodgkin’s lymphoma;receiver operating characteristic curve was used to analyze the predictive value of the semi-quantitative parameters for poor prognosis of Hodgkin’s lymphoma patients.Results:Mean SUVmax,MTV,and TLG of the 148 cases of Hodgkin’s lymphoma were 7.26±2.38,12.46±3.14 cm3,and 76.83±18.56 g,respectively.Significant variations in the Ann Arbor stage and clinical classification were observed with different levels of semi-quantitative parameters(P<0.05).The semi-quantitative parameters were not correlated with age and gender(P>0.05)but positively correlated with Ann Arbor stage and clinical classification(P<0.05).These parameters in the poor prognosis group were higher than those in the good prognosis group(P<0.05).The area under the curve(AUC)of SUVmax,MTV,and TLG in predicting the poor prognosis group was 0.881,0.875,and 0.838,with cut-off values of 7.264,12.898 cm3,and 74.580g,as well as specificity of 88.8%,84.0%,and 78.4%,and sensitivity of 87.0%,87.0%,and 78.3%,respectively;the AUC of the combined prediction was 0.986,with a specificity of 97.6%and sensitivity of 86.3%.Conclusion:The semi-quantitative 18F-FDG PET/CT parameters provide valuable insights for Hodgkin’s lymphoma prognosis assessment.

飞行时间、点扩散函数和高斯滤波对18F-FDG PET/CT肺结节SUV和SNR的影响

目的:探讨飞行时间(TOF)、点扩展函数(PSF)和高斯滤波(GF)对肺结节的标准化摄取值(SUV)和信噪比(SNR)的影响,为肺结节患者提供最佳的PET重建算法.方法:回顾性分析2020年12月至2022年3月在安徽医科大学第一附属医院行全身18F-FDGPET/CT检查的38例肺结节患者的PET/CT图像.采用滤波反投影(FBP)、有序子集最大期望值(OSEM)、OSEM+TOF、OSEM+PSF、OSEM+TOF+PSF和OSEM+TOF+PSF+GF[GF的半高宽(FWHM)分别为2、4、6、8和10 mm]重建算法进行图像重建,通过视觉评估PET图像质量和半定量方法分析肺结节的SNR和SUV.分别采用Holm-Sidak检验和Friedman检验分析不同重建算法间SUV和SNR的差异.结果:相比于FBP组,OSEM+TOF+PSF组SUVmax、SUVpeak、SUVmean 和 SNR 分别提高 8.02%(P>0.05)、10.72%(P<0.000 1)、19.05%(P<0.000 1)和 688.89%(P<0.000 1);相比于OSEM组,OSEM+TOF+PSF组SUVmax、SUVpeak、SUVmean和SNR分别提高 13.89%、25.60%、38.56%和 101.07%(均P<0.01);相比于OSEM+TOF组,OSEM+TOF+PSF组SUVpeak、SUVmean和SNR分别提高8.42%、12.76%和67.98%(均P<0.000 1),SUVmax降低2.76%(P>0.05);相比于OSEM+PSF组,OSEM+TOF+PSF组 SUVmax、SUVpeak、SUVmean 和 SNR分别提高 28.17%、19.19%、33.83%和12.15%(均 P<0.01).与 OSEM+TOF+PSF 组相比,OSEM+TOF+PSF+GF(2 mm FWHM)组 SUVmax、SUVpeak和SUVmean分别降低 12.12%、52.05%和9.24%,SNR提高3.42%(均P<0.05);OSEM+TOF+PSF+GF(4 mm FWHM)组 SUVmax、SUVpeak 和 SUVmean 分别降低 56.67%、69.79%和 34.75%,SNR 提高10.10%(均P<0.05);OSEM+TOF+PSF+GF(6 mm FWHM)组SUVmax、SUVpeak、SUVmean和SNR分别降低 115.91%、99.10%、73.63%和 1.75%(均P<0.05);OSEM+TOF+PSF+GF(8 mm FWHM)组 SUVmax、SUVpeak、SUVmean 和 SNR 分别降低 198.38%、140.65%、126.04%和 18.68%(均P<0.05);OSEM+TOF+PSF+GF(10 mm FWHM)组 SUVmax、SUVpeak、SUVmean和 SNR分别降低 311.94%、198.99%、201.85%和60.47%(均P<0.05).2名医师对FBP、OSEM、OSEM+TOF、OSEM+PSF和OSEM+TOF+PSF重建算法肺结节PET图像视觉评分优秀率均值分别为0、11.63%、25.58%、18.60%和50.00%;OSEM+TOF+PSF+GF(GF的FWHM分别为2、4、6、8和10mm)重建算法肺结节PET图像视觉评分优秀率均值分别为51.16%、54.65%、54.65%、33.72%和 10.47%.结论:在所有重建算法中,OSEM+TOF+PSF+GF(4 mm FWHM)重建算法可以获得最佳的肺结节PET图像视觉评分和SNR,但降低了肺结节的SUV.

EUS FNA of Altered Left Adrenal Gland Morphology Suggests Amending CT and PET-CT Attenuation Threshold Values That Predict Malignancy

Introduction: In the setting of an extra-adrenal malignancy, it is a recognized clinical challenge to try and distinguish a benign adrenal mass from a metastatic deposit. Current non-invasive diagnostic tools for adrenal gland evaluation include CT, MRI, PET and PET-CT. Diagnostic interpretative error can occur as evaluations rarely have complete cytologic or histologic correlation for concordance purposes. Aims: To establish the performance characteristics of non-contrast CT attenuation values (Hounsfield units-HU) and the optimal PET-CT maximum standard uptake value (SUVmax) for predicting adrenal malignancy when correlated with adrenal gland endoscopic ultrasound fine needle aspiration (EUS FNA) cytology results. Methods: A prospectively maintained EUS database was reviewed to identify consecutive patients who underwent a left adrenal gland FNA. Non-contrast CT attenuation values and SUVmax scores were calculated. EUS FNA cytology results were used as the reference standard for determining the presence of benign versus malignant adrenal gland status. Results: Sixty-two patients (69 ± 11 years) underwent adrenal EUS FNA, 34 (54.8%) of whom had a clinically suspected or established extra-adrenal malignancy. Non-invasive imaging was suggestive of abnormal adrenal morphology or altered PET-CT FDG activity in 45 (72.6%) patients. Elevated attenuation values (≥10 HU) by non-enhanced CT had a sensitivity and specificity of 100% and 34.6%, respectively. The SUVmax for malignant altered morphology was significantly higher than that for benign lesions [(8.5 ± 3.1 vs 3.3 ± 0.7;(p = 0.0001)]. ROC curve analysis indicated that an optimum cutoff SUVmax of ≥4.1 (AUC 0.92) yielded the best power distinction for malignancy with a sensitivity and specificity of 89% and 100%. Conclusion: When evaluating altered adrenal morphology by non-invasive methods, the performance characteristics of elevated CT attenuation values are suboptimal. But by adopting a SUVmax cut-off value of ≥4.1 could potentially improve such characteristics to detect malignancy.

DNA repair capacity correlates with standardized uptake values from 18F-fluorodeoxyglucose positron emission tomography/CT in patients with advanced non-small-cell lung cancer

Objective: The DNA repair capacity (DRC) of tumor cells is an important contributor to resistance to radiation and platinum-based drugs. Because DRC may be affected by tumor cell metabolism, we measured DRC in lymphocytes from patients with non-small-cell lung cancer (NSCLC) and compared the findings with the maximum standardized uptake value (SUVmax) on 18 F-fluorodeoxyglucose positron emission tomography (FDG PET) after (chemo)radiation therapy. Methods: This study included 151 patients with stage IA-IV NSCLC who had FDG PET at a single institution and donated blood samples before chemotherapy. We assessed the correlation of DRC, measured in peripheral T lymphocytes by a host-cell reac-tivation assay with SUVmax and their associations with overall survival (OS) time by hazards ratios calculated with a Cox pro-portional hazards regression model. Results: SUVmax of the primary tumor at diagnosis was inversely associated with lymphocyte DRC (r＝－0.175, P＝0.032), particularly among patients with advanced disease (r ＝ －0.218, P ＝ 0.015). However, △SUVmax of primary tumor was not significantly associated with DRC (r＝0.005, P＝0.968). SUVmax of regional lymph nodes at diagnosis (r＝－0.307, P＝0.0008) and after (chemo)radiation treatment (r＝－0.329, P＝0.034) and SUVmax of the primary tumor after (chemo)radiation treatment (r＝－0.253, P＝0.045) were also inversely associated with OS time. Conclusion: DRC was inversely associated with primary tumor SUVmax before treatment but not with △SUVmax after (chemo)radiation.

Significance of incidental focal fluorine-18 fluorodeoxyglucose uptake in colon/rectum,thyroid,and prostate:With a brief literature review

BACKGROUND Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT),a functional imaging method,is usually performed on the entire torso,and regions of unexpected suspicious focal hypermetabolism are not infrequently observed.Among the regions,colon,thyroid,and prostate were found to be the common organs in a recent umbrella review.Some studies reported that a high rate of malignancy was shown in incidentally identified focal hypermetabolic regions and suggested that further examinations should not be ignored.AIM To investigate the malignancy rate of incidental focal FDG uptake,useful PET parameters and their cutoffs in discrimination between malignant and benign lesions.METHODS Retrospectively,the final reports of 16510 F-18 FDG PET/CT scans performed at our hospital between January 2016 and March 2022 were reviewed to identify incidentally observed FDG uptake in the colon/rectum,thyroid,and prostate.The scans of patients with current or prior malignancies at each corresponding location,without the final reports of histopathology or colonoscopy(for colon and rectum)for the corresponding hypermetabolic regions,or with diffuse(not focal)hypermetabolism were excluded.Finally,88 regions of focal colorectal hypermetabolism in 85 patients(48 men and 37 women with mean age 67.0±13.4 years and 63.4±15.8 years,respectively),48 focal thyroid uptakes in 48 patients(12 men and 36 women with mean age 62.2±13.1 years and 60.8±12.4 years,respectively),and 39 focal prostate uptakes in 39 patients(mean age 71.8±7.5 years)were eligible for this study.For those unexpected focal hypermetabolic regions,rates of malignancy were calculated,PET parameters,such as standardized uptake value(SUV),capable of distinguishing between malignant and benign lesions were investigated,and the cutoffs of those PET parameters were determined by plotting receiver operating characteristic curves.RESULTS In the colon and rectum,29.5%(26/88)were malignant and 33.0%(29/88)were premalignant lesions.Both SUVmax and SUVpeak differentiated malignant/premalignant from benign lesions,however,no parameters could distinguish malignant from premalignant lesions.Higher area under the curve was shown with SUVmax(0.752,95%CI:0.649-0.856,P<0.001)and the cutoff was 7.6.In the thyroid,60.4%(29/48)were malignant.The majority were well-differentiated thyroid cancers(89.7%,26/29).The results of BRAF mutation tests were available for 20 of the 26 welldifferentiated thyroid cancers and all 20 had the mutation.Solely SUVmax differentiated malignant from benign lesions and the cutoff was 6.9.In the prostate,56.4%(22/39)were malignant.Only SUVmax differentiated malignant from benign lesions and the cutoff was 3.8.Overall,among the 175 focal hypermetabolic regions,60.6%(106/175)were proven to be malignant and premalignant(in colon and rectum)lesions.CONCLUSION Approximately 60%of the incidentally observed focal F-18 FDG uptake in the colon/rectum,thyroid,and prostate were found to be malignant.Of the several PET parameters,SUVmax was superior to others in distinguishing between malignant/premalignant and benign lesions.Based on these findings,incidental focal hypermetabolism should not be ignored and lead physicians to conduct further investigations with greater confidence.

Assessment of incidental focal colorectal uptake by analysis of fluorine-18 fluorodeoxyglucose positron emission tomography parameters

BACKGROUND Colon and rectal cancers are among the top five cancers worldwide in terms of their incidence and mortality rates.As the treatment options for cure include surgery even in specific advanced-stage cases,the early detection of lesions is important for applying active treatment methods.Fluorine-18 fluorodeoxyglucose(F-18 FDG)positron emission tomography/computed tomography(PET/CT)is an established imaging study for many types of cancers;however,physiologic uptake in the gastrointestinal tract is a frequent finding and may interfere with lesion identification.Nevertheless,as unexpectedly observed focal colorectal F-18 FDG uptake may harbor malignant lesions,further examination must not be avoided.AIM To assess the clinical implications of unexpected focal colorectal F-18 FDG uptake by analyzing FDG PET parameters.METHODS A total of 15143 F-18 FDG PET/CT scans performed at our hospital between January 2016 and September 2021 were retrospectively reviewed to identify incidentally observed focal colorectal FDG uptake.Finally,83 regions showing focal colorectal FDG uptake with final histopathological reports from 80 patients(45 men and 35 women with mean ages of 66.9±10.7 years and 63.7±15.3 years,respectively)were eligible for inclusion in the present study.Each focal hypermetabolic colorectal region was classified as malignant,premalignant,or benign according to the histopathological report.PET parameters such as maximum and peak standardized uptake value(SUVmax and SUVpeak),metabolic tumor volume(MTV),mean SUV of the metabolic tumor volume(mSUVmtv),and total lesion glycolysis(TLG)were measured or calculated for the corresponding hypermetabolic regions.Parametric and nonparametric statistical comparisons of these parameters were performed among the three groups.Receiver operating characteristic curves were plotted to identify cut-off values.RESULTS The detection rate of incidental focal colorectal uptake was 0.53%(80/15,143).Of the 83 regions with unexpected focal colorectal hypermetabolism,28.9%(24/83)were malignant,32.5%(27/83)were premalignant,and 38.6%(32/83)were benign.Overall,61.4% of the regions had malignant or premalignant lesions.SUVmax,SUVpeak,and mSUVmtv differentiated malignant and/or premalignant lesions from benign lesions with statistical significance(P<0.05).mSUVmtv3.5 differentiated malignant from benign lesions,with the largest area under the curve(AUC)of 0.792 and a cut-off of 4.9.SUVmax showed the largest AUC of 0.758 with a cut-off value of 7.5 for distinguishing between premalignant and benign lesions.Overall,SUVmax with a cut-off value of 7.6(AUC:0.770,95% confidence interval(CI):0.668-0.872;sensitivity,0.686;specificity,0.688)was a superior parameter for distinguishing between malignant/premalignant and benign lesions or physiologic uptake.No parameters differentiated malignant from premalignant lesions.Moderate or weak positive correlations were observed between the long diameter of the malignant lesions and PET parameters such as SUVpeak and some mSUVmtv.CONCLUSION Approximately two-thirds(61.4%)of incidental focal hypermetabolic colorectal regions were malignant/premalignant lesions,for which SUVmax was an independent diagnostic parameter.Unexpected suspicious focal colorectal FDG uptake should not be avoided and consideration for further evaluation is strongly recommended not to miss the two-thirds.

^(18)F-FDG PET/CT Deauville评分及ΔSUV_(max)评估弥漫性大B细胞淋巴瘤化疗中期预后的价值

目的探讨18氟-氟代脱氧葡萄糖正电子发射体层摄影技术/计算机体层摄影技术(^(18)F-FDG PET/CT)显像Deauville评分和最大标准化摄取值的变化(ΔSUV_(max))在弥漫性大B细胞淋巴瘤(DLBCL)化疗中期预后评估中的价值。方法回顾性分析78例DLBCL患者化疗中期^(18)F-FDG PET/CT图像资料。对ΔSUV_(max)、ΔSUV_(max)%进行受试者工作特征(ROC)曲线分析,分别采用ΔSUV_(max)及ΔSUV_(max)%的最佳临界值、Deauville评分分组,并按免疫组化结果分为生发中心(GCB)型和非GCB型。进行Kaplan-Meier生存曲线和Cox回归分析,分析Deauville评分法和ΔSUV_(max)法的预后评估能力。结果78例患者分为进展组24例和未进展组54例;进展组ΔSUV_(max)均值为(3.42±9.90),低于未进展组的(8.76±5.58),差异有统计学意义(P<0.05);进展组中位数ΔSUV_(max)%为34.88%,低于未进展组的78.16%,差异有统计学意义(P<0.01)。ΔSUV_(max)及ΔSUV_(max)%的曲线下面积(AUC)分别为0.667、0.882(P<0.01),分别以临界值7.95、67.34%分组,Kaplan-Meier分析显示2年无进展生存期(PFS)的差异有统计学意义(44.4%与82.4%,33.3%与95.6%,P<0.01)。Deauville<4分(PET阴性)组的2年PFS为91.9%,高于Deauville≥4分(PET阳性)组的48.8%,差异有统计学意义(P<0.01)。GCB型2年PFS为90.3%,高于非GCB型的55.3%,差异有统计学意义(P<0.01)。Cox多因素分析显示ΔSUV_(max)%及免疫组化分型为独立预测因素(P<0.01)。结论Deauville评分法和ΔSUV_(max)法在DLBCL化疗中期预后评估中均有较高的价值,ΔSUV_(max)%及免疫组化分型为PFS的独立预测因素。

^(99)mTc-MDP SPECT/CT显像定量分析对前列腺癌骨转移的诊断价值以及SUV的一致性研究

目的研究锝-99m-亚甲基二磷酸盐(^(99)mTc-MDP)单光子发射计算机断层成像(SPECT/CT)显像定量分析对前列腺癌骨转移的诊断价值以及标准化摄取值(SUV)的一致性,以期为临床诊疗提供参考。方法回顾性分析2021年1月到2022年3月在浙江金华广福肿瘤医院接受诊治的47例前列腺癌患者的^(99)mTc-MDP SPEC/CT显像影像学资料。所有患者均进行^(99)mTc-MDP SPECT/CT全身骨显像检查,收集患者骨转移瘤病灶平均体积、平均SUV(SUVmean)和最大SUV(SUVmax),并收集患者正常腰椎的SUVmax测量值,比较骨转移瘤病灶SUVmax测量值与正常腰椎的水平差异,采用ROC曲线分析SUVmax对前列腺癌骨转移的诊断效能。另外,分别采用CV、Bland-Altman、组内相关系数(ICC)分析同一观察者和不同观察者间测量结果的变异性和重复性。结果47例前列腺癌患者共测量前列腺癌骨转移瘤病灶337例,选取患者85个正常椎体进行对比,骨转移瘤病灶SUVmax测量值明显高于正常腰椎SUVmax测量值(P<0.05)。SUVmax对前列腺癌骨转移诊断价值的AUC值为0.876。不同观察者测量前列腺癌骨转移瘤病灶平均体积以及SUVmean具有极好的重复性(ICC值=0.979、0.967以及0.963、0.978);不同观察者测量前列腺癌骨转移瘤病灶SUVmax结果完全一致(ICC值=1.000)。同一观察者测量前列腺癌骨转移瘤病灶平均体积以及SUVmean具有极好的重复性(ICC值=0.952、0.965以及0.947、0.968);同一观察者两次测量前列腺癌骨转移瘤病灶SUVmax结果完全一致(ICC值=1.000)。2名观察者2次测量的SUVmean变异性明显高于SUVmax,差异均有统计学意义(均P<0.01)。结论^(99)mTc-MDP SPECT/CT显像定量分析对前列腺癌骨转移具有较好诊断价值,前列腺癌骨转移患者^(99)mTc-MDP显像SUV中,SUVmax的一致性在同一观察者或不同观察者较SUVmean更好,有利于临床评价前列腺癌骨转移患者的治疗效果。

^(18)F-FDG PET/CT显像和血清学指标对前列腺肿瘤的诊断价值

目的 研究^(18)F-氟代脱氧葡萄糖(^(18)F-fluorodexyglucose,^(18)F-FDG)PET/CT显像和前列腺血清学指标诊断前列腺肿瘤的价值。方法 回顾性分析2013年8月至2021年12月在浙江大学医学院附属第二医院经病理证实的95例疑似前列腺肿瘤患者的^(18)F-FDG PET/CT图像与前列腺血清学指标。根据病理检查结果分为恶性组(n=77)和良性组(n=18)。采用受试者工作特征(receiver operating characteristic,ROC)曲线分析前列腺病灶的最大标准摄取值(maximum standardized uptake value,SUV_(max))与血清总前列腺特异性抗原(total prostate specific antigen,tPSA)、游离前列腺特异性抗原(free prostate specific antigen,fPSA)及游离/总前列腺特异性抗原比值(free/total prostate specific antigen,f/t-PSA)诊断前列腺良恶性病灶的最佳截断界值。结果 ROC曲线显示,SUV_(max)、tPSA、fPSA和f/t-PSA诊断前列腺良恶性病灶的最佳截断值分别为4.47、46.67 ng/mL、11.11 ng/mL和0.10。SUV_(max)、tPSA、fPSA和f/t-PSA的ROC曲线下面积(area under the curve,AUC)分别为0.658、0.897、0.842和0.836。^(18)F-FDG PET/CT显像、tPSA、f PSA和f/t-PSA对前列腺肿瘤的诊断敏感度分别是81.8%、97.4%、92.2%和83.1%,特异度分别是61.1%、27.8%、50.0%和50.0%,准确度分别是77.9%、84.2%、84.2%和76.8%。恶性组SUV_(max)、tPSA和fPSA均高于良性组,f/t-PSA低于良性组(均P<0.05)。^(18)F-FDG PET/CT检查显示,72例有远处转移病灶。结论 SUV_(max)、tPSA、fPSA和f/t-PSA均能鉴别前列腺良恶性病灶。^(18)F-FDG PET/CT显像在探测远处病灶方面更具有优势,能够为临床决策提供更好的帮助。

^(18)F-PSMA-1007 PET/CT与mp-MRI对前列腺癌的检测效能及与病理分级的相关性研究

目的探讨18氟标记前列腺特异性膜抗原-1007正电子发射计算机体层摄影(fluorine-18 prostate specific membrane antigen 1007-positron emission tomography/computed tomography,^(18)F-PSMA-1007 PET/CT)与多参数磁共振成像(multi-parameter magnetic resonance imaging,mp-MRI)单独及联合对前列腺癌(prostate cancer,PCa)的检测效能,并比较最大标准化摄取值(maximum standardized uptake value,SUV_(max))、表观弥散系数(apparent diffusion coefficient,ADC)、SUV_(max)/ADC、T1、T2、质子密度(proton density,PD)值与PCa病理分级的相关性。材料与方法回顾性分析我院2020年4月至2022年9月疑似PCa并拟行穿刺活检或手术的患者病例,最终50例患者被纳入研究,其中42例确诊PCa。按照国际泌尿病理协会(International Society of Urological Pathology,ISUP)分级共分为5组,包括中高级别组(分级≥4)25例和低级别组(分级1~3)17例,比较不同分组的SUV_(max)、ADC及SUV_(max)/ADC的差异。采用Spearman相关分析SUV_(max)、ADC、SUV_(max)/ADC、T1、T2、PD值之间的相关性及分别与ISUP分级的相关性。以病理为金标准,分析^(18)F-PSMA-1007 PET/CT与mp-MRI单独及联合对前列腺良恶性的检测效能。绘制受试者工作特征(receiver operating characteristic,ROC)并计算曲线下面积(area under the curve,AUC)、敏感度和特异度,评价SUV_(max)、ADC、SUV_(max)/ADC及联合参数诊断效能,通过DeLong检验比较AUC间的差异。结果PCa高级别组与低级别组的ADC值、SUV_(max)、SUV_(max)/ADC差异均有统计学意义(P均<0.001)。50例患者的ADC值与SUV_(max)呈负相关性(r=-0.516,P<0.05),42例确诊PCa患者的ADC值与ISUP分级呈负相关(r=-0.616,P<0.05),SUV_(max)、SUV_(max)/ADC与ISUP分级呈正相关(r=0.549、0.639,P均<0.05)。20例完成定量磁共振图像编译(magnetic resonance image compilation,MAGiC)序列患者T1、T2、PD值与ISUP分级无相关性(r=0.045、0.202、0.028,P均>0.05);T1、T2值与ADC值呈正相关(r=0.616,r=0.756,P均<0.05),PD值与ADC值呈负相关(r=-0.506,P<0.05)。SUV_(max)与T1、T2、PD值没有明显相关性(r=-0.132,r=-0.422,r=0.230,P均>0.05)。ROC曲线分析显示,SUV_(max)的AUC为0.940,差异有统计学意义(P<0.001),以7.80为临界值,诊断PCa的敏感度为83.33%,特异度为100.00%;ADC值的AUC为0.970,差异有统计学意义(P<0.001),以1.20×10^(-3)mm^(2)/s为临界值,诊断PCa的敏感度为95.24%,特异度为87.50%;SUV_(max)/ADC的AUC为0.970,差异有统计学意义(P<0.001),以6.43×10^(3)为临界值,诊断PCa的敏感度为90.48%,特异度为100%;SUV_(max)和ADC联合的AUC为0.976,差异有统计学意义(P<0.001),以0.85为临界值,诊断PCa的敏感度为90.48%,特异度为100.00%。结论联合^(18)F-PSMA-1007 PET/CT与mp-MRI可以提高对PCa的诊断效能;ADC值、SUV_(max)及SUV_(max)/ADC能够区分低危与中高危PCa。

校正PET图像上病灶SUV值的研究

进行定量分析是PET技术重要的优势,但由于部分容积效应(PVE)的影响,使图像定量值失真。本研究建立一种校正PET图像上病灶标准摄取值(SUV)的方法。基于PET图像PVE形成原理及模拟实验,分析病灶图像上最大SUV与病灶真实大小、病灶真实SUV之间的关系,建立由图像上最大值校正SUV的方法,称之为最大值校正法。并通过PET模型实验,对建立的方法进行验证。结果:①最大值校正法:建立了用图像上病灶SUV最大值计算SUV校正值的公式。②实验验证:对不同大小的病灶,其SUV均得到了一定程度的校正,尤其对小于分辨率的病灶(4.7mm、3mm),校正效果更显著,SUV校正值的准确度提高了53.55%、54.17%和50.37%、68.52%。结论:建立了一种简单校正PET图像上病灶SUV的方法——最大值校正法。

FDG-PET/CT图像SUV阈值在放疗计划设计时的应用

目的:通过对FDG-PET/CT图像信息的预处理,寻找可以通过设定标准摄取值(standardized uptake value,SUV)来量化确定靶区的方法。方法:选择有明确病理诊断的肺癌患者15例入组研究,并以下述4种方式勾画靶区(GTV):①自开发可以设定SUV值并据此勾画轮廓的软件,设定SUV=2.5,由软件自动勾画靶区(GTV-AUTO);②基于CT窗宽/窗位在-800 Hu^800 Hu的条件下勾画靶区(GTV-CT);③基于FDG-PET的视觉法勾画靶区(GTV-VIS);④在治疗计划系统(TPS)上通过调整窗宽/窗位使其达到SUV=2.5时,由医生勾画靶区(GTV2.5)。比较上述4种方法确定的靶区的体积差异。结果:GTV-AUTO与GTV-2.5的比较无差异。以CT为基础勾画的靶区(GTV-CT)小于以PET为基础勾画的靶区,其中GTV-CT的体积明显小于GTV-AUTO(P=0.007)和GTV-2.5(P=0.003)。结论:自开发的软件可以精确量化靶区的勾画,并使靶区的确定更加规范。同时,根据病人行PET-CT扫描时相关参数的计算结果及预设的SUV值,在TPS上勾画靶区(GTV),也可以达到此目的。

符合线路显像与PET显像中SUV的比较研究

目的比较符合线路显像标准摄取值(SUV)与PET显像的SUV。方法用双探头符合显像仪及PET对模型显像,分别采用不同的重建算法重建,测定图像上热灶的SUV。结果对直径小于30mm热灶,相同大小时,PET得到的SUV高于符合线路显像;无论对PET还是符合线路显像,随热灶大小增加SUV增加;SUV与重建算法有关;选取的感兴趣区(ROI)越大,获得的SUV越小;由PET图像获得的热灶SUV可见,当热灶大于2倍的系统分辨率时,SUVmax接近热灶的真实值(SUVtrue)。结论符合线路显像的SUV低于PET显像;病灶大小、重建算法、ROI大小均影响SUV。

^(18)F-FDGPET/CT显像在正常人各器官的SUV与CT值分布

目的对正常人体各器官的标准化摄取值(SUV)与CT值进行界定。方法对各种实质性脏器勾画感兴趣区(ROI),测定SUV与CT值,并进行分析研究。结果正常人体各脏器的SUV和CT值与其生理及结构特性有关。结论该研究结果为PET/CT图像评价及半定量分析提供了参考依据。

PET/CT SUV_(max)值、核抗原Ki-67与淋巴瘤分期之间的相关性探讨

目的:探讨PET/CT SUVmax值、核抗原Ki-67与淋巴瘤分期间的相互关系。材料与方法:对39例具有18F-FDG PET/CT资料和免疫组化资料(Ki-67)但未行治疗的淋巴瘤患者进行回顾性分析。根据临床综合评价对所有患者进行Ann Arbor分期,由计算机工作站获得每个病灶的SUVmax,随访时间6～41个月。为扩大样本量,本文将Ⅰ、Ⅱ、Ⅲ、Ⅳ期合为早期(Ⅰ期～Ⅱ期)、晚期(Ⅲ期～Ⅳ期)两组,通过BinaryLogistic回归分析探讨SUVmax值、Ki-67指数与早晚分期之间的关系,以Spearman相关分析观察SUVmax值和Ki-67指数之间的相关性及其密切程度。结果:①回归分析结果显示SUVmax值与淋巴瘤分期无关(P=0.163);Ki-67指数与淋巴瘤早、晚分期显著相关(P<0.001),且Ki-67指数越高,分期越趋向晚期。②由相关分析得出,SUVmax值和Ki-67指数之间呈显著正相关(P<0.001),但关系不密切(相关系数为0.251)。结论:Ki-67指数与淋巴瘤临床分期之间、SUVmax与Ki-67指数之间均成显著正相关。

99mTcO4-SPECT/CT定量显像在测定毒性弥漫性甲状腺肿患者SUV值和甲状腺体积中的应用

目的·探讨单光子发射计算机断层成像术/电子计算机断层扫描(single-photon emission computed tomography/computed tomography,SPECT/CT)定量显像测定毒性弥漫性甲状腺肿(toxic diffuse goiter,GD;又称Graves病)患者SUV摄取值及甲状腺体积的可行性。方法·选入64例Graves病患者,其中男性患者21例,女性患者43例,年龄(44.1±14.1)岁。所有受试者均进行血清FT3、FT4水平检测,以及2 h、24 h摄131I率检查。所有患者在静脉注射(5.5±0.5)mCi([204.2±16.8)MBq]99mTcO4-放射性显像剂后,进行颈部SPECT/CT断层及平面显像。通过40%阈值法测定Graves病患者的甲状腺定量摄取均值SUVmean、最大值SUVmax及三维甲状腺体积Vol3D,对SUVmean、SUVmax与血清甲状腺激素水平及摄131I率的相关性进行分析。通过Xeleris工作站(GE Healthcare)以及传统公式分别测定三维甲状腺体积Vol3D和二维甲状腺体积Vol2D,对Vol3D和Vol2D进行分析比较。结果·Graves病患者的甲状腺定量摄取值SUVmean和SUVmax分别为(262.5±110.2)g/mL和(471.4±192.1)g/mL,与血清甲状腺激素水平FT3、FT4之间均无相关性(P>0.05),与2 h摄131I率和24 h摄131I率之间具有正相关性(均r>0且P=0.000)。此外,Vol3D与Vol2D之间呈正相关(r=0.853,P=0.000)。结论·99mTcO4-SPECT定量显像测定甲状腺三维体积及SUV定量摄取值方法临床简便可行,可为Graves病患者诊断及评估治疗剂量提供临床依据,具有重要的临床诊断意义。

不同重建矩阵对18F-FDG PET图像质量和SUV值的影响

目的:探讨不同重建矩阵对18F-FDG PET图像质量和标准摄取值(standard uptake value,SUV)的影响,以持续获得高质量的PET图像。方法:选择符合美国国家电气制造商协会标准的模体进行体模实验,选择2018年5月至2019年6月于南京市第一医院核医学科行18F-FDG PET/CT全身扫描的40例患者(共96处病灶)图像进行临床实验。对重建矩阵分别为128×128、150×150、192×192、256×256、512×512和600×600时的PET图像质量采用变异系数(coefficient of variation,CV)、对比度、信噪比及肝脏SUVmax、SUVmean、SUVSD、CVliver值和病灶SUVmax进行评估。结果:(1)不同重建矩阵所得模体PET图像微球均清晰可见,重建矩阵为192×192时,模体PET图像信噪比取得最大值,CV值取得最小值。(2)重建矩阵为192×912和256×256时,临床实例PET图像病灶清晰度和肝脏均匀度较高。不同重建矩阵所得病灶SUVmax和肝脏SUVmean差异无统计学意义(F=0.757,P=0.581;F=0.002,P>0.999),肝脏SUVmax、SUVSD和CVliver差异具有统计学意义(F=7.879、19.51、37.34,P均<0.0001)。重建矩阵为256×256时,病灶SUVmax取得最大值,且肝脏SUVmean趋于稳定。结论:18F-FDG PET图像质量和SUV值受重建矩阵影响较大,重建矩阵为256×256时可满足临床诊断需要,重建矩阵为192×192时图像质量最佳。

每床位采集时间对^(18)F-FDG PET图像质量和SUV值的影响

目的探讨每床位采集时间对氟[^(18)F]脱氧葡萄糖(^(18)F-FDG)PET图像质量和标准摄取值(StandardUptake Value,SUV)的影响。方法本研究包括体模实验和23例患者(48处病灶)行^(18)F-FDGPET检查的回顾性分析。参照美国国家电气制造商协会标准,在国际电工委员会体模中37 mm微球和腔体注射比例为4:1的^(18)F-FDG。PET数据重建采用有序子集最大期望法+飞行时间技术+点扩散技术,图像质量评估采用变异系数(CV)值、对比度、信噪比、肝脏SUV_(mean)、SUV_(sd)、CV_(liver)值和病灶SUV_(max)。结果体模CV值随着采集时间的增加呈下降趋势,信噪比呈上升趋势,对比度趋于稳定。每床位采集时间为5 min时临床实例PET图像质量最优,2 min时图像病灶依然清晰可见。不同采集时间对应的肝脏SUV_(mean)、SUV_(sd)和CV_(liver)值得分差异均具有统计学意义(F=497.10、F=14.59、F=46.80,P均<0.0001),不同采集时间对应的病灶SUV_(max)整体得分差异无统计学意义(F=0.30,P=0.88),且不同体质量和剂量组SUV_(max)得分差异亦无统计学意义(P均>0.05)。结论 ^(18)F-FDG PET图像质量和SUV值受采集时间影响较大,延长采集时间可有效抑制PET图像噪声。同时显示^(18)F-FDG PET/CT全身快速扫描具有满足临床诊断需求的可行性。

TOF-PET/MR和TOF-PET/CT在体部恶性肿瘤SUV_(max)值的比较

目的探讨时间飞行(TOF)技术PET/CT和PET/MR检查体部恶性病变SUV_(max)值的一致性。方法回顾性分析接受TOF-PET/CT和TOF-PET/MR检查的体部恶性肿瘤患者20例,分为先PET/CT后PET/MR组和先PET/MR后PET/CT组,每组10例。采用Bland-Altman图评价两次检查病灶SUV_(max)值的一致性,采用多因素方差分析评价扫描顺序和机器类型对病灶的SUV_(max)测量值的影响。结果 TOF-PET/CT与TOF-PET/MR检查病灶的SUV_(max)值有较好的一致性[先PET/CT后PET/MR组:均值差为3.06,95%CI(-7.5,13.6),先PET/MR后PET/CT组:均值差3.0,95%CI(-2.4,8.3)]。扫描顺序对于恶性病灶的SUV_(max)有影响(F=46.00,P<0.001),而机器类型对恶性病灶的SUV_(max)值无影响(F=0.005,P=0.95)。结论 TOF-PET/MR和TOF-PET/CT在体部恶性病变SUV_(max)值测量方面具有相当的诊断价值,且延迟显像SUV_(max)的增加与采集时间有关,而与检查机器类型无关。