Tumor characteristics of ductal carcinoma in situ of breast visualized on [F-18] fluorodeoxyglucose-positron emission tomography/computed tomography: Results from a retrospective study

AIM To clarify clinicopathological features of ductal carcinoma in situ(DCIS) visualized on [F-18] fluorodeoxyglucosepositron emission tomography/computed tomography(FDG-PET/CT).METHODS This study retrospectively reviewed 52 consecutive tumors in 50 patients with pathologically proven pure DCIS who underwent [F-18] FDG-PET/CT before surgery. [F-18] FDG-PET/CT was performed after biopsy in all patients. The mean interval from biopsy to [F-18] FDGPET/CT was 29.2 d. [F-18] FDG uptake by visual analysis and maximum standardized uptake value(SUVmax) was compared with clinicopathological characteristics.RESULTS[F-18] FDG uptake was visualized in 28 lesions(53.8%) and the mean and standard deviation of SUVmax was 1.63 and 0.90. On univariate analysis, visual analysis and the SUVmax were associated with symptomatic presentation(P = 0.012 and 0.002, respectively), palpability(P = 0.030 and 0.024, respectively), use of core-needle biopsy(CNB)(P = 0.023 and 0.012, respectively), ultrasound-guided biopsy(P = 0.040 and 0.006, respectively), enhancing lesion ≥ 20 mm on magnetic resonance imaging(MRI)(P = 0.001 and 0.010, respectively), tumor size ≥ 20 mm on histopathology(P = 0.002 and 0.008, respectively). However, [F-18] FDG uptake parameters were not significantly associated with age, presence of calcification on mammography, mass formation on MRI, presence of comedo necrosis, hormone status(estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2), and nuclear grade. The factors significantly associated with visual analysis and SUVmax were symptomatic presentation(P = 0.019 and 0.001, respectively), use of CNB(P = 0.001 and 0.031, respectively), and enhancing lesion ≥ 20 mm on MRI(P = 0.001 and 0.049, respectively) on multivariate analysis.CONCLUSION Although DCIS of breast is generally non-avid tumor, symptomatic and large tumors(≥ 20 mm) tend to be visualized on [F-18] FDG-PET/CT.

Comparisons between glucose analogue 2-deoxy-2-(^(18)F)fluoro-D-glucose and ^(18)F-sodium fluoride positron emission tomography/computed tomography in breast cancer patients with bone lesions

AIM: To compare 2-deoxy-2-(18F)fluoro-D-glucose(18F-FDG) and 18F-sodium (18F-NaF) positron emission tomography/computed tomography (PET/CT) accuracy in breast cancer patients with clinically/radiologically suspected or known bone metastases.METHODS: A total of 45 consecutive patients with breast cancer and the presence or clinical/biochemical or radiological suspicion of bone metastatic disease underwent 18F-FDG and 18F-fluoride PET/CT. Imaging results were compared with histopathology when available, or clinical and radiological follow-up of at least 1 year. For each technique we calculated: Sensitivity (Se), specificity (Sp), overall accuracy, positive and negative predictive values, error rate, and Youden’s index. McNemar’s χ2 test was used to test the difference in sensitivity and specificity between the two diagnostic methods. All analyses were computed on a patient basis, and then on a lesion basis, with consideration ofthe density of independent lesions on the co-registered CT (sclerotic, lytic, mixed, no-lesions) and the divergent site of disease (skull, spine, ribs, extremities, pelvis). The impact of adding 18F-NaF PET/CT to the work-up of patients was also measured in terms of change in their management due to 18F-NaF PET/CT findings.RESULTS: The two imaging methods of 18F-FDG and 18F-fluoride PET/CT were significantly different at the patient-based analysis: Accuracy was 86.7% and 84.4%, respectively (McNemar’s χ2 = 6.23, df = 1, P = 0.01). Overall, 244 bone lesions were detected in our analysis. The overall accuracy of the two methods was significantly different at lesion-based analysis (McNemar’s χ2 = 93.4, df = 1, P < 0.0001). In the lesion density-based and site-based analysis, 18F-FDG PET/CT provided more accurate results in the detection of CT-negative metastasis (P < 0.002) and vertebral localizations (P < 0.002); 18F-NaF PET/CT was more accurate in detecting sclerotic (P < 0.005) and rib lesions (P < 0.04). 18F-NaF PET/CT led to a change of management in 3 of the 45 patients (6.6%) by revealing findings that were not detected at 18F-FDG PET/CT.CONCLUSION: 18F-FDG PET/CT is a reliable imaging tool in the detection of bone metastasis in most cases, with a diagnostic accuracy that is slightly, but significantly, superior to that of 18F-NaF PET/CT in the general population of breast cancer patients. However, the extremely high sensitivity of 18F-fluoride PET/CT can exploit its diagnostic potential in specific clinical settings (i.e., small CT-evident sclerotic lesions, high clinical suspicious of relapse, and negative 18F-FDG PET and conventional imaging).

Positron Emission Tomography-Computed Tomography (PET-CT) in Head and Neck Pathology

Cancer of the head and neck is often devastating and the morbidity associated with its treatment is substantial. Positron Emission Tomography-Computed Tomography (PET-CT) combines the power of biological / molecular imaging with the anatomic detail of CT in order to provide a very sensitive and specific imaging tool for the evaluation of head and neck pathology. PET can aid the clinician in establishing diagnosis, staging, (It has been shown to be more accurate than CT), assessing, prognosis and determining response to therapy. Lymphoma, melanoma, multiple myeloma, leukemia, salivary gland tumors, odontogenic carcinomas, soft tissue sarcomas, thyroid, parathyroid, lacrimal gland and bone / cartilage tumors are some of the entities where PET-CT may be useful. (Tumors of salivary glands and of odontogenic tissue are particularly difficult to diagnose due to the relative infrequency when compared with other tumors and the extremely vast histologic variation).It is important to note that carcinoma metastasis, is the most common malignancy found within the mandibular bone. PET-CT and skeletal scintigraphy are both very sensitive and specific in these types of patients.

Preoperative [18]fluorodeoxyglucose-positron emission tomography/computed tomography in early stage breast cancer: Rates of distant metastases

AIM To investigate rates of distant metastases(DM) detected with [18]fluorodeoxyglucose-positron emissiontomography/computed tomography(^(18)FDG-PET/CT) in early stage invasive breast cancer.METHODS We searched the English language literature databases of PubM ed, EMBASE, ISI Web of Knowledge, Web of Science and Google Scholar, for publications on DM detected in patients who had ^(18)FDG-PET/CT scans as part of the staging for early stages of breast cancer(stage Ⅰ?and Ⅱ), prior to or immediately following surgery. Reports published between 2011 and 2017 were considered. The systematic review was conducted according to the PRISMA guidelines.RESULTS Among the 18 total studies included in the analysis, the risk of DM ranged from 0% to 8.3% and 0% to 12.9% for stage Ⅰ?and Ⅱ invasive breast cancer, respectively. Among the patients with clinical stage Ⅱ, the rate of occult metastases diagnosed by ^(18)FDG-PET/CT was 7.2%(range, 0%-19.6%) for stage ⅡA and 15.8%(range, 0%-40.8%) for stage ⅡB. In young patients(< 40-yearold), ^(18)FDG-PET/CT demonstrated a higher prevalence of DM at the time of diagnosis for those with aggressive histology(i.e., triple-negative receptors and poorly differentiated grade).CONCLUSION Young patients with poorly differentiated tumors and stage ⅡB triple-negative breast cancer may benefit from ^(18)FDG-PET/CT at initial staging to detect occult DM prior to surgery.

Qualitative visual trichotomous assessment improves the value of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in predicting the prognosis of diffuse large B-cell lymphoma

Introduction:Fluorine-18 fluorodeoxyglucose(18F-FDG)positron emission tomography/computed tomography(PET/CT)is a powerful tool for monitoring the response of diffuse large B-cell lymphoma(DLBCL)to therapy,but the criteria to interpret PET/CT results remain under debate.We investigated the value of post-treatment PET/CT in predicting the prognosis of DLBCL patients when interpreted according to qualitative visual trichotomous assessment(QVTA)criteria compared with the Deauvil e criteria.Methods:In this retrospective study,final PET/CT scans of DLBCL patients treated with rituximab-based regimens between October 2005 and November 2010 were interpreted using the Deauvil e and QVTA criteria.Survival curves were estimated using Kaplan-Meier analysis and compared using the log-rank test.Results:A total of 253 patients were enrol ed.The interpretation according to the Deauvil e criteria revealed that 181patients had negative PET/CT scan results and 72 had positive results.The 3 year overal survival(OS)rate was significantly higher in patients with negative scan results than in those with positive results(91.6%vs.57.5%,P<0.001).The72 patients with positive scan results according to the Deauville criteria were divided into two groups by the interpretation according to the QVTA criteria:29 had indeterminate results,and 43 had positive results.The 3 year OS rate was significantly higher in patients with indeterminate scan results than in those with positive results(91.2%vs.33.5%,P<0.001)but was similar between patients with negative and indeterminate scan results(91.6%vs.91.2%,P=0.921).Conclusions:Compared with the Deauvil e criteria,using the QVTA criteria for interpreting post-treatment PET/CT scans of DLBCL patients is likely to reduce the number of false positive results.The QVTA criteria are feasible for therapeutic outcome evaluation and can be used to guide risk-adapted therapy.

Impact of random and scattered coincidences from outside of field of view on positron emission tomography/computed tomography imaging with different reconstruction protocols

Image quality in positron emission tomography(PET)is affected by random and scattered coincidences and reconstruction protocols.In this study,we investigated the effects of scattered and random coincidences from outside the field of view(FOV)on PET image quality for different reconstruction protocols.Imaging was performed on the Discovery 690 PET/CT scanner,using experimental configurations including the NEMA phantom(a body phantom,with six spheres of different sizes)with a signal background ratio of 4:1.The NEMA phantom(phantom I)was scanned separately in a one-bed position.To simulate the effect of random and scatter coincidences from outside the FOV,six cylindrical phantoms with various diameters were added to the NEMA phantom(phantom II).The 18 emission datasets with mean intervals of 15 min were acquired(3 min/scan).The emission data were reconstructed using different techniques.The image quality parameters were evaluated by both phantoms.Variations in the signal-to-noise ratio(SNR)in a 28-mm(10-mm)sphere of phantom II were 37.9%(86.5%)for ordered-subset expectation maximization(OSEM-only),36.8%(81.5%)for point spread function(PSF),32.7%(80.7%)for time of flight(TOF),and 31.5%(77.8%)for OSEM+PSF+TOF,respectively,indicating that OSEM+PSF+TOF reconstruction had the lowest noise levels and lowest coefficient of variation(COV)values.Random and scatter coincidences from outside the FOV induced lower SNR,lower contrast,and higher COV values,indicating image deterioration and significantly impacting smaller sphere sizes.Amongst reconstruction protocols,OSEM+PSF+TOF and OSEM+PSF showed higher contrast values for sphere sizes of 22,28,and 37 mm and higher contrast recovery coefficient values for smaller sphere sizes of 10 and 13 mm.

Findings of ¹⁸F-Fluorodeoxyglucose Positron-Emission Tomography in Methotrexate-Related Lymphoproliferative Disorder

Introduction: The use of methotrexate (MTX) for rheumatoid arthritis (RA) is increasing. However, the immune suppression state leads to the occurrence of lymphoproliferative disorder (MTX-LPD). The purpose of this study was to describe the findings of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in MTX-LPD patients, and compare it with non-MTX-related malignant lymphoma (ML). Materials and Methods: We retrospectively reviewed 11 MTX-LPD patients (9 female, mean age 68.3 years) and 21 ML patients (7 female, mean age 60.6 years) with a histopathological diagnosis. FDG-PET imaging was performed using a standard oncology procedure. We assessed the disease distribution based on FDG-PET images and measured the maximum standardized up take values (SUVmax) for each region. Results: Mean values of SUVmax in MTX-LPD and ML were 14.6 and 17.2, respectively (p = 0.49). In MTX-LPD, 55 lesions met the Cotswold classification, consisting of 37 nodal and 18 extranodal lesions. In ML, 82 lesions were found, consisting of 68 nodal and 14 extranodal lesions. MTX-LPD showed a higher incident of the involvement in extranodal lesions throughout the whole body (p < 0.001). Conclusion: Because this disease occurs widely throughout the whole body, we need to pay attention to the less frequent sites as well when performing PET imaging in patients with MTX-LPD.

基于定量CT身体组分、^(18)F-FDG PET/CT显像预测手术联合新辅助化疗治疗早期乳腺癌预后的价值

目的 分析定量CT (QCT)身体组分、^(18)F-氟脱氧葡萄糖正电子发射型计算机断层显像(^(18)F-FDG PET-CT)对手术联合新辅助化疗(NAC)治疗早期乳腺癌患者预后的预测效能,为临床治疗提供参考。方法 选取2020年3月至2022年10月于南阳市第二人民医院接受手术联合NAC治疗的82例早期乳腺癌患者纳入研究,在NAC前和化疗1、3个周期后检测记录QCT参数[L_(1)、L_(2)水平的皮下脂肪面积(SFA)、内脏脂肪面积(VFA)、骨密度(BMD)、L_(3)水平的椎旁肌肉面积(TMA)]、^(18)F-FDG PET/CT显像的最大标准摄取值(SUV_(max))、肿瘤代谢体积(MTV)。NAC结束后进行手术,随访12个月(失访2例),依据有无复发转移分为预后良好组43例和预后不良组37例,比较不同预后患者的QCT参数、^(18)F-FDG PET/CT显像指标,采用受试者工作特征(ROC)曲线获取曲线下面积(AUC)分析其对早期乳腺癌患者预后的预测效能。结果化疗1个周期后,预后良好组患者的SFA、BMD、VFA、MA水平分别为(45.23±4.07) cm^(2)、(128.97±26.53) mg/m^(2)、(78.07±6.69) cm^(2)、(37.36±5.74) cm^(2),明显高于预后不良组的(42.52±3.32) cm^(2)、(112.54±25.82) mg/m^(2)、(73.73±7.25) cm^(2)、(32.94±5.31) cm^(2),差异均有统计学意义(P<0.05);化疗3个周期后,预后良好组患者的SFA、BMD、VFA、MA水平分别为(40.95±3.92) cm^(2)、(113.55±15.87) mg/m^(2)、(73.59±6.17) cm^(2)、(32.67±4.98) cm^(2),明显高于预后不良组的(37.51±3.56) cm^(2)、(95.18±17.45) mg/m^(2)、(70.30±5.14) cm^(2)、(28.52±4.42) cm^(2),差异均有统计学意义(P<0.05);化疗1个周期后,预后良好组患者的SUV_(max)、MTV分别为5.43±1.25、(3.86±0.87)×10^(4)mm,明显低于预后不良组的6.04±1.07、(4.27±0.85)×10^(4)mm,差异均有统计学意义(P<0.05);化疗3个周期后,预后良好组患者的SUV_(max)、MTV分别为3.94±1.06、(2.61±0.70)×10^(4)mm,明显低于预后不良组的4.73±1.21、(3.05±0.93)×10^(4)mm,差异均有统计学意义(P<0.05);经ROC曲线分析结果显示,SFA、BMD、VFA、MA、SUV_(max)、MTV联合预测手术联合NAC治疗早期乳腺癌患者预后的AUC分别为0.898 (95%CI:0.809~0.954)、0.919 (95%CI:0.836~0.968)。结论 NAC过程中检测QCT参数、^(18)F-FDG PET/CT显像指标可预测手术联合NAC治疗早期乳腺癌患者的预后,联合预测的价值较高。

一体化PET/MR在乳腺疾病中的应用进展

近年来新出现的一体化PET/MR,实现了PET与MR真正的生理同步,对多种疾病的诊断有着独特的优势,在乳腺疾病中的应用也值得关注。本文从PET/MR技术特点、示踪剂、工作流程、在乳腺疾病筛查、良恶性鉴别诊断和乳腺癌病情评估中的应用等多个方面进行综述如下。

^(18)F-FDOPA PET/CT定量分析提高早期帕金森病的诊断效能

目的探讨6-^(18)F氟-L-多巴(^(18)F-FDOPA)PET/CT半定量分析及人工智能平台对帕金森病(PD)的诊断价值。资料与方法回顾性分析2018年1月—2019年12月南京医科大学附属南京医院经临床确诊的56例PD患者,其中33例早期(Hoehn-YahrⅠ~Ⅱ级),23例晚期(Hoehn-YahrⅢ~Ⅳ级);选取本院体检中心同期健康对照者27例,行^(18)F-FDOPA PET/CT。于HERMES BRASS平台计算受试者纹状体各亚区与枕叶体积计数比(SORs),完成基于感兴趣区的脑半定量分析,观察早期和晚期PD患者纹状体各亚区不对称性。使用人工智能技术对PD组和健康对照组纹状体各亚区SORs行主成分分析,观察数据聚集度和组间区分度。结果与健康对照组相比,晚期PD患者尾状体、前壳核、后壳核和纹状体整体SORs显著降低(t=9.02~11.72,P<0.0001),对应的曲线下面积分别为0.952、0.973、0.995和0.982。早期PD患者纹状体各亚区不对称指数分别为尾状核(7.61±5.50)%、前壳核(11.43±8.97)%、后壳核(17.17±11.63)%、纹状体(10.65±7.46)%。PD组和健康对照组相比,主成分分析有显著区分度,PD组纹状体^(18)F-FDOPA摄取显著降低,早期PD患者对侧后壳核损失最显著,下降百分比为34%。结论平台半定量分析^(18)F-FDOPA PET/CT图像,为PD早期诊断和鉴别诊断提供客观半定量数值,纹状体特别是壳核的不对称性可能是PD早期诊断的重要参数。

Role of FDG PET-CT in evaluation of locoregional nodal disease for initial staging of breast cancer

Fluorodeoxyglucose positron emission tomography/computed tomography(FDG PET/CT) is not indicated or recommended in the initial staging of early breast cancer. Although it is valuable for detecting distant metastasis, providing prognostic information, identifying recurrence and evaluating response to chemotherapy, the role of FDG PET/CT in evaluating locoregional nodal status for initial staging of breast cancer has not yet been well-defined in clinical practice. FDG PET/CT has high specificity but compromised sensitivity for identifying axillary nodal disease in breast cancer. Positive axillary FDG PET/CT is a good predictor of axillary disease and correlates well with sentinel lymph node biopsy(SLNB). FDG PET/CT may help to identify patients with high axillary lymph node burden who could then move directly to axillary lymph node dissection(ALND) and would not require the additional step of SLNB. However, FDG PET/CT cannot replace SLNB or ALND due to unsatisfactory sensitivity. The spatial resolution of PET instruments precludes the detection of small nodal metastases. Although there is still disagreement regarding the management of internal mammary node(IMN) disease in breast cancer, it is known that IMN involvement is of prognostic significance, and IMN metastasis has been associated with higher rates of distant metastasis and lower overall survival rates. Limited clinical observationssuggested that FDG PET/CT has advantages over conventional modalities in detecting and uncovering occult extra-axillary especially IMN lesions with upstaging the disease and an impact on the adjuvant management.

抗LGI1抗体自身免疫性脑炎^(18)F-FDG PET/CT影像学特征

目的研究抗富亮氨酸胶质瘤失活1蛋白(leucine-rich glioma-inactivated 1,LGI1)抗体自身免疫性脑炎(autoimmune encephalitis,AE)患者头部^(18)F-脱氧葡萄糖(^(18)F-deoxyglucose,FDG)正电子发射计算机断层显像(positron emission tomography,PET)/电子计算机断层显像(computed tomography,CT)影像学特点,探讨PET/CT在抗LGI1-AE早期诊断中的应用价值。方法回顾性分析2014年10月至2020年11月在首都医科大学附属北京天坛医院神经内科诊断为LGI1-AE的43例患者[其中急性期24例(56%),慢性期19例(44%)]的资料,分析患者^(18)F-FDG PET/CT的影像及临床特征。结果^(18)F-FDG PET显像结果显示,40例(93%)LGI1-AE患者出现明显的代谢异常,而只有26例(60%)患者出现异常磁共振(magnetic resonance imaging,MRI)信号(P<0.05)。^(18)F-FDG PET代谢异常在治疗后是可逆的,大多数患者出院后^(18)F-FDG PET的代谢几乎均正常。LGI1-AE患者的高代谢区位于基底节区(basal ganglia,BG)和内侧颞叶(medial temporal lobe,MTL)。在33例(77%)患者中观察到BG区高代谢,72%的患者表现出MTL高代谢。共有22例患者(51%)表现出面臂肌张力障碍性癫痫发作(faciobrachial dystonic seizures,FBDS),其余患者表现出非FBDS症状(49%)。FBDS患者中有7例(7/21)检测到仅BG区高代谢,而非FBDS患者中只有2例患者(2/19)检测到BG区高代谢(33%vs 10%,P<0.05)。结论^(18)F-FDG PET/CT对抗LGI1-AE患者的早期诊断阳性率高。FBDS患者多表现为仅BG区高代谢,这表明BG区可能参与FBDS发作。

PET/MR成像的临床应用述评

一体化正电子发射断层/磁共振(positron emission tomography/magnetic resonance, PET/MR)成像系统融合了PET成像的高精确度和数据定量特性,以及MR成像的优质软组织分辨率和多功能序列成像特性,使其在恶性肿瘤、心血管系统疾病和神经系统疾病的诊疗中得到广泛的应用。因此,确认一体化PET/MR成像的临床价值,探讨其临床适应证,明确PET/MR成像在临床上的定位,寻找其最适宜的发展环境显得至关重要。本文就PET/MR成像在相关疾病中的应用及其研究现状进行了述评,突出了相较于正电子发射断层/电子计算机断层扫描(positron emission tomography/computed tomography, PET/CT)成像,PET/MR成像系统在疾病诊断、病情进展评估和预后预测中的优势及限制。并对一体化PET/MR成像系统在未来临床应用中的发展走向进行了展望。总之,本述评旨在为临床及放射科医生提供PET/MR成像在临床应用方面的实证依据,以释放其在临床实践中的潜力。

PET示踪剂在阿尔茨海默病早期诊断中的研究进展

阿尔茨海默病(Alzheimer′s disease,AD)是一种发病机理极其复杂的神经退行性疾病,以认知功能障碍和记忆丧失为特征,涉及多种生理、病理过程。早期诊断是AD预防和治疗的关键。正电子发射断层成像(PET)技术能够在分子层面准确检测神经元与脑组织中细微的生理变化,为AD早期诊断提供依据。从生物标志物的分类入手,介绍了脑中蛋白变性与神经元损伤的相关靶点,根据亲和力、半衰期、结合区域、药代动力学、分析方法以及结果相关性等几个重要参数,综述了各类PET示踪剂的研究现状,指出目前PET示踪剂开发面临的问题,认为未来研究应从以下几个方面展开:神经炎症相关PET示踪剂的开发;已有示踪剂的进一步评估和优化;示踪剂结果分析方法的规范化和标准化。

一体化^(18)F-FET PET/MR术前评估成人胶质瘤患者MGMT基因启动子甲基化状态

目的 旨在研究一体化^(18)F-氟乙基酪氨酸(^(18)F-fluoroethyltyrosine, ^(18)F-FET)正电子发射断层成像(positron emission tomography, PET)/MR对成人胶质瘤的O6-甲基鸟嘌呤DNA甲基转移酶(O6-methylguanine DNA methyltransferase, MGMT)基因启动子甲基化状态的鉴别能力。材料与方法 回顾性分析未经活检或治疗的胶质瘤患者资料16例,均完成一体化PET/MR扫描,包括^(18)F-FET PET、常规MRI及体素内不相干运动(intravoxel incoherent motion, IVIM)成像。以靶本比(target-background ratio, TBR)=1.6为阈值对PET图像进行感兴趣体积(volume of interest, VOI)分割,通过刚性配准获得肿瘤VOI对应的IVIM图及其参数表观扩散系数(apparent diffusion coefficient, ADC)、真实扩散系数(true diffusion coefficient, D)、伪扩散系数(pseudo diffusion coefficient, D^(*))、灌注分数(perfusion fraction, f)、分布扩散系数(distributed diffusion coefficient, DDC)和异质性指数(heterogeneity index, α),使用pyradiomics对各参数进行特征提取,获得对应的一阶灰度直方图特征。计算每个IVIM参数图对应的特征值与^(18)F-FET PET参数的关系,并利用组间比较和受试者工作特征(receive operating characteristic, ROC)曲线分析探究PET和IVIM参数对MGMT启动子甲基化的区分能力。结果 IVIM-α的两个特征值90分位值(r=0.526,P<0.05)和最大值(r=0.520, P<0.05)与PET参数平均标准摄取值(meanstandarduptakevalue,SUVmean)呈正相关;IVIM-α和SUVmean在MGMT启动子甲基化状态阳性和阴性两组之间的差异有统计学意义(P<0.05),阳性组的IVIM-α均值和SUVmean显著高于阴性组;融合IVIM-α均值和SUVmean对MGMT启动子甲基化状态进行区分的曲线下面积(area under the curve, AUC)为0.77。结论 基于一体化PET/MR的^(18)F-FET PET和IVIM参数能够有效预测胶质瘤的MGMT启动子甲基化状态。

乳腺专用PET在乳腺癌中的临床应用进展

乳腺癌是目前世界范围内发病率最高的肿瘤,早发现、早诊断对于乳腺癌患者的治疗及预后具有重要意义。乳腺专用PET(dedicated breast PET,dbPET)是一种新兴的分子成像设备,在临床实践中用于乳腺癌的检测和肿瘤生物学的评估,具有比传统影像学手段更高的空间分辨率,可以识别乳房内放射性示踪剂摄取的详细形态学模式。鉴于国内外对dbPET的综合性分析较少,文章从dbPET在乳腺癌的筛查、诊断、摄取模式、新辅助化疗后评估及PET显像剂等方面的应用进行综述。

^(18)F-FDG PET/CT摄取值及血清载脂蛋白A1、谷胱甘肽对不同运动障碍亚型帕金森病的预测价值

目的:探讨^(18)F-脱氧葡萄糖(^(18)F-FDG)正电子发射断层扫描-计算机断层扫描(PET/CT)摄取值及血清载脂蛋白A1(Apo A1)、谷胱甘肽(GSH)用于不同运动障碍亚型帕金森病的预测价值。方法:选取2020年12月至2022年12月在临沂市人民医院就诊的84例帕金森病患者,根据国际运动障碍协会统一帕金森病评定量表(MDS-UPDRS)将患者分为震颤为主型(TD)组(50例)和姿势不稳或步态障碍型(PIGD)组(34例)。比较不同运动障碍亚型帕金森病患者^(18)F-FDGPET/CT的^(18)F-FDG摄取值、血清Apo A1及GSH水平,并通过受试者工作特征(ROC)曲线分析上述3项指标联合预测不同运动障碍亚型帕金森病的价值;验证^(18)F-FDG摄取值、血清Apo A1及GSH联合检测对不同运动障碍亚型帕金森病患者预测结果与患者实际亚型的一致性。结果:TD组丘脑的^(18)F-FDG摄取值显著低于PIGD组;TD组血清Apo A1水平显著高于PIGD组、TD组血清GSH水平显著高于PIGD组,差异有统计学意义(t=3.669、2.758、2.824,P<0.05);ROC曲线下面积(AUC)分析显示,丘脑^(18)F-FDG摄取值、Apo A1及GSH联合预测不同运动障碍亚型帕金森病的AUC为0.858;^(18)F-FDG摄取值、血清Apo A1及GSH联合对不同运动障碍亚型帕金森病患者预测结果与患者实际亚型的一致性较高(Kappa=0.804)。结论:^(18)F-FDG PET/CT摄取值、血清Apo A1及GSH联合应用对不同运动障碍亚型帕金森病有较好的的预测价值。

^(18)F-FBB PET脑部图像采集中不同时长对感兴趣区域定量参数的影响研究

目的:探讨氟18(^(18)F)贝他苯(^(18)F-FBB)PET脑部图像不同采集时长对标准化摄取值(SUV)的影响。方法:选取2021年5-6月在解放军总医院进行^(18)F-FBB PET检查的8名受试者,其中健康受试者5名,轻度认知障碍(MCI)患者3例。所有受试者均行^(18)F-FBB PET检查,在注射^(18)F-FBB注射液(3.7~5.5 MBq/kg)后90~110 min连续采集脑部动态PET图像20 min。在其他重建参数不变的情况下,分别选择0~1、0~3、0~5、0~10、0~15和0~20 min进行图像重建,在每组图像的双侧额叶皮层、双侧颞叶皮层、双侧顶叶皮层、后扣带回和小脑皮层勾划相同的感兴趣区域(ROI),获得各区相应的平均标准化摄取值(SUVmean)。对比分析各组数据图像与0~20 min图像中不同ROI的SUVmean的差异。结果:图像重建时采集0~1、0~3、0~5和0~10 min的图像与标准采集0~20 min图像SUVmean具有显著差异(t=-7.569~-2.410,P<0.05),0~15 min图像在双侧额叶、双侧颞叶、双侧顶叶皮层及后扣带回等区域的SUVmean值与标准0~20 min采集图像无明显差异(P>0.05),只在小脑皮层区域两者之间存在差异(t=-5.597,P<0.001)。结论:图像采集时长为15 min时可以达到与20 min图像采集时长相近的结果,可缩短检查时间,提高受检舒适度及配合度,具有临床应用价值。

基于PnI的全数字PET成像软件

传统正电子发射断层成像(PET)系统采用模拟电路对信号进行处理,通过符合电路实现符合事件甄别,软件算法多集中于处理投影数据和图像数据,损失了生成图像前的大量信息,算法可扩展性相对较差。全数字PET系统利用精确采样和全数字处理带来硬件极简化和软件极大化的设计理念,将更多操作交由软件算法完成,具有过程数据完整、算法丰富且替换优化方便的特点。把探测器和算法当作“积木”,即插即成像(PnI)平台构建成像协议层、成像算法层和成像设备层,实现了成像过程定义、成像算法扩展和多种设备定义,从而支持动物、临床和各种应用专用型全数字PET系统的搭建。而且,全数字PET配合PnI平台可以将信息挖掘的入口从图像层面提前到闪烁脉冲数据层面,支持更多算法的灵活接入。基于以上背景,本文综述PnI即插即成像软件的研究进展,具体说明全数字PET系统结构、成像过程、软件架构以及应用案例,旨在提高科学家搭建数字PET科研仪器的灵活性,为开发快速高效搭建不同PET系统与软件算法提供参考。

^(68)Ga-FAPI-04 PET/CT对胰腺癌的诊断价值及对肿瘤分期的影响

目的:探讨^(68)Ga标记的成纤维细胞激活蛋白抑制剂(fibroblast activation protein inhibitor,FAPI)-04正电子发射断层显像/X线计算机体层成像(positron emission tomography and computed tomography,PET/CT)对初诊胰腺癌的诊断价值及对肿瘤分期的影响。方法:回顾性收集2021年8月至2023年8月于重庆大学附属肿瘤医院就诊的134例因怀疑胰腺占位的患者临床及影像资料。分析^(68)Ga-FAPI-04 PET/CT对胰腺癌原发灶及转移灶的诊断价值;并与传统CT比较,分析^(68)Ga-FAPI-04 PET/CT对胰腺癌肿瘤分期的影响。结果:共计纳入134例患者,其中胰腺癌127例,良性病变7例。^(68)Ga-FAPI-04 PET/CT对胰腺癌原发灶、区域淋巴结及远处转移灶检出率分别为100%(127/127)、68.63%(35/51),95.35%(41/43)。胰腺癌中位最大标准化摄取值(standard uptake value maxium,SUVmax)为14.92,高于胰腺良性病变中位SUVmax(6.1)(Z=−2.921,P=0.003)。与传统CT比较,^(68)Ga-FAPI PET/CT检查后共有32.28%(41/127)胰腺癌患者TNM分期发生改变。3.94%(5/127)患者改变了治疗方案。结论:^(68)Ga-FAPI-04 PET/CT对胰腺癌原发灶诊断具有较高的敏感性,较传统CT可发现更多远处转移病灶,改善患者M分期,有助于全面评估全身肿瘤负荷、制定治疗计划。