PET和PET/CT在头颈部恶性肿瘤中的临床应用价值

正电子发射断层成像(Positron emission tomography,PET)能较早揭示生物机体异常功能、代谢变化,由于它的灵敏度高、特异性好,在临床肿瘤诊断中起着重要作用.但其影像解剖结构不如CT和MRI清晰,将PET与CT进行同机图像融合的PET,CT则弥补了这个不足,并将各自的优势相结合,代表了核医学显像的未来.     

Total-body PET/CT临床应用进展

Total-body(TB)PET/CT扫描仪于2019年用于人体显像并逐步在临床开展。相比传统PET/CT,TB PET/CT具有所需显像剂剂量低、采集时间短、图像质量高、可全身动态成像及以多种显像剂检查等优点,提高了诊断肿瘤、评价疗效及预测预后的准确性。本文就TB PET/CT临床应用进展进行综述。     

18F-FDG PET/CT显像在不明原发灶淋巴结转移癌中的应用价值

原发灶不明的淋巴结转移癌（Metastatic lymph nodecarcinoma of unknown primary site,LCUP）是指各部位淋巴结经活检或针吸病理细胞学证实为转移癌,而经反复仔细全面的常规检查,仍查不到原发灶的转移癌（不包括淋巴瘤）,这类原发灶不明的转移性肿瘤约在肿瘤中占2.3%-4.2%[1],患者预后差,从诊断开始,     

18F-FDG PET/CT在胰腺癌的应用

目的：探讨18F-FDG PET/CT对胰腺癌的诊断价值。方法：61例胰腺占位性病变患者行18F-FDG PET/CT显像,并与同机CT相比较。所有病例最后确诊依据手术或活组织病理学检查、多种影像学检查及临床随访确诊,随访时间＞5个月。结果：在61例胰腺占位性病变患者中,胰腺癌48例,良性病变13例。18F-FDG PET/CT对胰腺癌诊断的灵敏度、特异性、准确性、阳性预测值、阴性预测值分别为100%、76.9%、95.1%、94.1%、100%。胰腺癌病灶平均SUV 4.5±1.9与胰腺良性病变平均SUV 2.3±2.5两者差异显著（P=0.001）。48例胰腺癌确诊时18F-FDG PET/CT发现36例胰腺癌病灶侵犯毗邻组织。在胰腺癌患者中,24例（50.0%）患者发生淋巴结转移,25例（52.1%）存在远处脏器或/和组织转移。结论：18F-FDG PET/CT在胰腺癌的诊断、临床分期中有重要价值。18F-FDG PET/CT应作为CT诊断胰腺癌的一种补充方法。     

PET/CT骨骼显像方法学探讨

目的：利用PET/CT检查设备,对Na18F断层骨显像进行方法学研究。资料和方法：PET/CT、小型回旋加速器均采用美国通用电气公司生产的设备,型号分别为Discovery LS和Minitrace;骨显像剂为Na18F（放化纯为95.3％）。采用不同断层骨显像方法对比分析,探讨人体Na18F摄取速度、显像采集速度及显像时间对断层骨显像的影响。结果：适宜的骨显像方法能提高Na18F断层骨显像的质量。结论：PET/CT检查骨肿瘤较SPECT平面骨显像具有更好的灵敏性和图像质量。     

11C-乙酸盐PET/CT显像在肿瘤诊断中的显像原理与临床应用

近年来许多研究认为11C-乙酸盐作为氨基酸及甾醇合成的前体,可用于肿瘤的诊断,它与目前用于肿瘤显像的主要示踪剂--反应细胞内乏氧糖代谢的氟代脱氧葡萄糖(11F-fluorodeoxygluose,18F-FDG)不同.     

比较PET/CT与PET/MRI诊断成人淋巴瘤

目的 比较PET/CT与PET/MRI诊断成人淋巴瘤的效能。方法 前瞻性观察45例淋巴瘤患者，行全身PET/CT和PET/MR检查，分别由2名医师独立评估PET/CT和PET/MRI，获得病灶最大标准摄取值（SUV_max）及对应D值、D^*值和f值，分析两种模式的诊断效能及分期差异。结果 PET/CT与PET/MRI均测出55个淋巴结和5个结外病灶的SUV_max，基于体素内不相干运动（IVIM）模型测出39个病灶的对应值。医师间对阳性病灶检测率一致性极强（k=1.000），PET/CT与PET/MRI的一致性极强（k=0.956）；对于淋巴瘤分期，PET/CT与PET/MRI一致性极强（k=0.965）；PET/CT与PET/MRI的SUV_max呈高度相关（r=0.892，P<0.001），D值与SUV值低度相关（r=-0.312，P<0.050），f值与SUV值呈中度相关（r=0.520，P<0.001）。结论 PET/CT与PET/MRI对成人均有良好诊断效能，PET/MRI可提高淋巴瘤诊断及分期的准确率，多参数联合可预测和评估肿瘤异质性。     

颅内原发性恶性淋巴瘤18F-FDG PET/CT显像3例

病例例1,男,60岁。因头痛、言语不清3周余为主诉入院。间断性发热,抗炎后好转。血沉40.0s（0～15s）,鳞状上皮细胞癌抗原升高2.3ug/L（0～1.5ug/L）;细胞角蛋白抗原32.61（0～3.6）。胸片示双侧胸腔积液,以左侧明显。胸水穿刺未找到癌细胞及抗酸杆菌。曾行抗结核治疗两周余。     

胸腹部淋巴结结核18F-FDG PET/CT显像1例

病例女,53岁,1周前体检时腹部增强CT,B超均发现腹膜后多发肿大淋巴结,部分融合,包绕胰头周围（4月前腹部B超未见肿大淋巴结）,肿瘤标志物均未见异常,无不适主诉,体温正常,体重无改变,现未经任何治疗.为明确诊断行体部18F-FDG PET/CT检查.     

18F-FDG PET/CT在霍奇金淋巴瘤治疗中的应用

使用18 氟标记的氟脱氧葡萄糖（18F fluorodeoxyglucose,18F FDG）正电子发射断层扫描结合计算机断层扫描（PET/CT）的功能显像在霍奇金淋巴瘤(Hodgkin lymphoma,HL)的分期中具有明确的作用,现已成为HL的主要显像模式。其作为一种预测治疗工具,通过反应适应疗法的应用而不断发展。已有大量临床研究表明18F FDG PET/CT对HL具有非常高的预后诊断价值,可以提高分期的准确性,鉴别残留肿瘤和纤维化组织。HL中的反应适应性治疗方法既可以通过减低剂量来降低对低风险患者的毒性,同时还通过增加对高风险患者的治疗强度以改善预后。本综述介绍了18F FDG PET/CT在HL中的诊断分期、治疗期间和治疗结束时的应用进展,并对总肿瘤代谢体积这一新的功能预后因素进行了探讨。     

FDG PET/CT in the liver: lesions mimicking malignancies

Purpose

18F-fluorodeoxyglucose (FDG) PET/CT is invaluable in managing liver lesions, in particular in the evaluation of suspected liver metastases. It is both sensitive and specific in detecting liver metastases from a wide range of primary cancers, and may change clinical management, most commonly by detecting additional lesions and decreasing the number of futile surgeries. However, some benign lesions may also show increased metabolic activity which can lead to false positive PET findings. We describe some of these lesions and their imaging characteristics that may help in differentiating them from malignant metastases.

Methods

We reviewed all whole body FDG PET/CT studies performed over a 5-year period in our institution, and identified those with focal liver lesions showing increased FDG uptake for which histological results were available.

Results

A majority of lesions showing increased metabolic activity were due to malignant disease, such as metastases or primary liver tumours. However, we also found increased FDG uptake in non-neoplastic lesions such as Cryptococcosis, abscesses, and secondary inflammation from cholecystitis. Increased metabolic activity was also seen in some benign neoplasms such as hepatic adenomas and hemangioendotheliomas.

Conclusion

FDG PET/CT is currently the most sensitive non-invasive imaging modality for the detection of hepatic metastases, particularly from the gastrointestinal tract. False positive results are rare, and have been described mainly in abscesses. However, other lesions can also show increased metabolic activity, and failure to differentiate these from metastases may result in inappropriate treatment.     

肝癌经动脉栓塞化疗后FDG PET显像的临床价值 ——附10例FDG PET和CT结果对照

目的：探讨核医学影像诊断技术－FDG PET在中晚期肝癌栓塞化疗后随诊中的临床价值,并着重比较FDG PET与CT在判断介入治疗后局部肿瘤坏死及残留状况方面的互补作用。方法：10例临床确诊的肝癌患者,术前CT或MRI示肿瘤短轴均大于4cm,经栓塞化疗后6－10个月同期行FDG PET和CT检查,并采用双盲法将FDG PET与CT结果进行比较。结果：10例CT扫描结果显示,4例肿瘤内碘油分布密集,3例肿瘤内碘油分布稀疏,3例肿瘤内碘油短期内排空;PET显示其中6例肿瘤内碘油分布稀疏或碘油短期内排空者局部肿瘤内及周边区域均有FDG明显浓聚的病变,4例肿瘤内碘油分布密集者,FDG PET均显示肿瘤边缘部位可见到不规则的放射性分布浓聚现象。结论：中晚期肝癌栓塞化疗后病灶边缘部分多有肿瘤存活或残留,但CT检查不能准确判断这一现象,而FDG PET在准确定位肿瘤残留病灶方面正好弥补了CT扫描的不足。     

F-18 FDG PET/CT在继发性噬血细胞综合征中的临床价值研究

本研究旨在探讨F-18 FDG PET/CT在噬血细胞综合征（HPS）的诊断和预后判断中的作用。回顾性分析了11例行F-18 FDG PET/CT检查的HPS患者,评估了F-18 FDG PET/CT对HPS相关的恶性肿瘤的诊断价值,计算了骨髓和脾脏的最大标准摄取值（SUVmax）,对骨髓和脾脏的SUVmax与HPS的多个实验室参数以及临床转归的关系进行了分析。结果表明：11患者中4例伴恶性肿瘤;通过F-18 FDG PET/CT检测判断HLH患者是否伴有恶性肿瘤的敏感性、特异性和准确性分别为100.0%、66.7%和75.0%;骨髓和脾脏的SUVmax与实验室参数无显著的相关性;预测患者预后的脾脏SUVmax值和骨髓SUVmax值的最佳截断点分别为3.10和3.47;单因素分析提示,骨髓和脾脏中F-18 FDG高摄取患者的存活时间较短。结论：F-18 FDG PET/CT在继发性HPS的病因诊断和预后判断中具有重要作用。     

Detecting recurrence of gastric cancer: the value of FDG PET/CT

Purpose  In order to assess the diagnostic performance of Positron emission tomography/Computed tomography (PET/CT) for detecting recurrence in gastric cancer patients with clinical or radiologic suspicion of recurrence after surgical resection. Materials and methods  Over a 4-year period, 105 post-operative patients with gastric cancer, who underwent PET/CT due to clinical or radiologic suspicion of recurrence during follow-up, were collected after confirming their PET/CT findings. The number and site of positive FDG uptake were retrospectively analyzed, and were correlated with the final diagnosis, by calculating the diagnostic values and assessing the causes of misdiagnosis. Results  Of all 105 patients, 75 patients were confirmed to have true recurrence with 108 recurrence sites. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for diagnosing true recurrence on a per-person basis were 75%, 77%, 89%, 55%, and 75%, respectively. On a per-lesion basis, 75 (69%) of 108 true recurrences showed positive FDG uptake, while 75 (89%) of 84 positive FDG uptake was confirmed to have true recurrence. Conclusion  PET/CT was relatively accurate in detecting recurrence in post-operative patients with gastric cancer. Moreover, PET/CT might be helpful in confirming the presence of recurrence particularly in patients who were highly suspicious of recurrence, because of its high positive predictability.     

Preoperative staging of colorectal cancer: CT vs. integrated FDG PET/CT

Accurate preoperative staging is essential in determining the optimal therapeutic planning for individual patients. The computed tomography (CT) in the preoperative staging of colorectal cancer, even if controversial, may be useful for planning surgery and/or neoadjuvant therapy, particularly when local tumor extension into adjacent organs or distant metastases are detected. There have been significant changes in the CT technology with the advent of multi-detector row CT (MDCT) scanner. Advances in CT technology have raised interest in the potential role of CT for detection and staging of colorectal cancer. In recent studies, MDCT with MPR images has shown promising accuracy in the evaluation of local extent and nodal involvement of colorectal cancer. Combined PET/CT images have significant advantages over either alone because it provides both functional and anatomical data. Therefore, it is natural to expect that PET/CT would improve the accuracy of preoperative staging of colorectal cancer. The most significant additional information provided by PET/CT relates to the accurate detection of distant metastases. For the evaluation of patients with colorectal cancer, CT has relative advantages over PET/CT in regard to the depth of tumor invasion through the wall, extramural extension, and regional lymph node metastases. PET/CT should be performed on selected patients with suggestive but inconclusive metastatic lesions with CT. In addition, PET/CT with dedicated CT protocols, such as contrast-enhanced PET/CT and PET/CT colonography, may replace the diagnostic CT for the preoperative staging of colorectal cancer.     

18F-FDG PET/CT显像对胃癌术前分期的临床价值

目的：探讨18F-脱氧葡萄糖（18F-FDG）PET/CT显像对胃癌TNM分期的临床价值。方法：对33例胃癌初诊患者于手术前2周内行18F-FDG PET/CT检查,将33例手术治疗患者的PET/CT结果与病理学检查、其他影像结果及临床随访结果相比较。结果：将PET/CT显像TNM分期与手术病理学检查TNM分期进行对比分析,结果证明对胃癌原发灶的检出,18F-FDG PET灵敏度为84.8％,PET/CT为100％。18F-FDG PET/CT显像与手术病理学检查比较,对T分期、N分期、M分期的一致性分别为81.8％、75.8％、93.9％,对TNM分期的一致性为90.9％（Kappa值分别为0.514、0.557、0.767、0.759,P<0.01)。结论：18F-FDG PET/CT显像对胃癌的TNM分期具有重要价值,且PET/CT检查结果与手术病理学检查结果有较好的一致性,但应注意印戒细胞癌等细胞类型易出现的假阴性。     

Response to neoadjuvant therapy in locally advanced rectal cancer: assessment with diffusion-weighted MR imaging and 18FDG PET/CT

The aim of this study was to evaluate the correlation between the changes of SUV_max and of apparent diffusion coefficient (ADC) before and after neoadjuvant therapy, to enable us predict the therapy response, in patients with locally advanced rectal cancer (LARC). A total of 30 patients with LARC who underwent CRT were recruited for our study. All the patients underwent a whole body 18F-FDG-PET/CT scan and a pelvic MR examination including DW imaging for staging (PET/CT1 and RM1), and after the chemoradiation therapy (PET/CT2, and RM2). Histopathologic analysis of rectal specimen, according to tumor regression grade (Mandard??s criteria) was used as the standard reference. MR and PET-CT images were analyzed, and measurements of ADC values and SUV_max were taken. Diagnostic performance for selection of complete responders (TRG1?C2) and overall diagnostic accuracy for each item were calculated. After neoadjuvant therapy, all patients were submitted to surgery. According to Mandard??s criteria, 21 tumors showed complete (TRG1) or subtotal regression (TRG2) and were classified as responders; nine tumors were classified as non responders (TRG3, 4, and 5). In all the patients, mean value of SUV_max in PET/CT1 was higher than those in PET/CT2 (P?<?0.001), whereas mean ADC value was lower in RM1 than RM2 (P?<?0.001), with a significant percentage decrease of values after the treatment (P?<?0.005).The best predictors cut-off values for TRG response were SUV_max of 4.4 and ADC of 1.28?×?10³?mm²/s with sensitivity, specificity accuracy, negative predictive value, and positive predictive values of 77.3%, 88.9%, 80.7%, 61.5%, and 94.4%, respectively. We conclude from the overall data of this study that the absolute values of SUV_max and ADC of rectal lesion after CRT were the best parameters to define the response to treatment, by differentiating fibrosis from viable tumor tissue.     

氟-18-氟代脱氧葡萄糖PET/CT不同时相延迟显像的比较

目的:比较研究氟-18-氟代脱氧葡萄糖(18F-FDG)PET/CT不同时相延迟显像对良恶性肿瘤的鉴别诊断价值,确定延迟显像的最佳时间选择。方法:回顾分析80例明确诊断且同时进行18F-FDGPET/CT三时相显像的患者共148个病灶。第1次显像时间为药物注射后64min;第2次(早期延迟显像)时间为110min;第3次(晚期延迟显像)时间为233min。分析每个病灶的最大标准摄取值(SUV),并根据公式滞留指数(RI1)=(SUV2-SUV1)/SUV1×100%;RI2=(SUV3-SUV1)/SUV1×100%进行计算。通过特征工作曲线(ROC)比较分析两次延迟显像的诊断效率。结果:80例患者共148个病灶。109个为恶性病灶,39个为良性病灶。恶性病灶的RI1和RI2分别为(14.8±13.1)%和(10.8±20.5)%;良性病灶的RI1和RI2分别为(11.3±28.2)%和(9.3±42.4)%。RI1的曲线下面积为0.627±0.050(P=0.013),RI2的曲线下面积为0.57±0.06(P<0.05)。早期延迟显像的诊断效率明显高于晚期延迟显像。结论:在应用18F-FDGPET/CT延迟显像进行良恶性鉴别诊断时,采取早期延迟显像可以获得较高的诊断效率。     

18F-FDG PET/CT对肾上腺肿瘤良恶性的诊断价值的Meta分析

目的 采用Meta分析系统评价18氟代脱氧葡萄糖正电子发射计算机断层显像（18F FDG PET/CT）对肾上腺肿瘤良恶性的诊断价值。方法 计算机检索PubMed、EMbase、The Cochrane Library、中国知网（CNKI）、万方、中文科技期刊等数据库,查找有关18F FDG PET/CT对肾上腺肿瘤良恶性诊断性试验研究文献。由2名研究员按同一标准分别进行文献筛选、提取资料和评价文献质量,采用Meta DiSc1.4软件进行Meta分析。结果 最终纳入20篇文献,肾上腺肿瘤患者1 481例,肾上腺病变共计1 663个。Meta分析结果示,PET/CT对肾上腺肿瘤良恶性的诊断灵敏度为0.92,特异度为0.92,阳性似然比为9.54,阴性似然比为0.09,合并效应量为139.60,受试者曲线下面积为0.9708。18F FDG在肿瘤摄取值/肝脏摄取值＞1时代谢参数SUVmax比值的诊断效能最高（灵敏度为0.95、特异度为0.93、受试者曲线下面积为0.9789）。结论 18F FDG PET/CT代谢参数中SUVmax比值(tumor/liver＞1)对肾上腺肿瘤的良恶性诊断效能最高。