肺癌分期的PET/CT表现与血清VEGF表达的关系

目的：探讨肺癌TNM分期的PET／CT成像表现特点与血清VEGF蛋白表达水平的关系。方法：53例肺癌患者治疗前，对其进行PET／CT检查，再用酶联免疫夹心法检测血清VEGF蛋白的表达水平．分析肺癌的T分期和转移（淋巴结和远处转移）的PET／CT表现特征与血清VEGF表达的关系。结果：经PET／CT成像分析．其中T1 11例、T2 9例、T3 18例、T4 15例；纵隔淋巴结转移22例，9例患者有远处转移.肺癌患者的血清VEGF表达的平均水平为（378．02±180．79）ng／L，与正常健康人组差异有统计学意义（P〈0．05）。在不同的低T分期（T1与T2）患者中，血清VEGF表达水平无显著性差异，而低T分期（T1与T2）患者与高T分期（T3与T4）患者中的血清VEGF表达差异有统计学意义（P〈0．05）。纵隔淋巴结转移组血清VEGF表达水平为（561．50±104．55）ng／L．与非淋巴结转移组间比较差异有统计学意义（t=12．21，P〈0．05）：远处转移组血清VEGF表达水平为（614．11±158．81）ng／L．血清VEGF的表达明显与远处转移相关（t=5．30，P〈0．05）。结论：1）肺癌患者血清VEGF水平呈高表达；2）肺癌患者VEGF的表达水平与发生淋巴结转移和远处转移有关；3）随着肺癌TNM分期增加，血清VEGF蛋白表达增强，     

氟脱氧葡萄糖PET-CT确定食管癌淋巴结放疗靶区的可行性研究

目的分析~(18)FDG PET-CT诊断食管癌淋巴结转移的优势及确定淋巴结放疗靶区的可行性。方法回顾性分析30例食管癌患者的临床病理资料,分析PET-CT在诊断淋巴结转移方面的优势,基于CT和PET-CT确定淋巴结大体肿瘤靶区(GTVN)和临床靶区(CTVN),根据术后病理分析PET-CT在确定淋巴结放疗靶区中的价值。结果13例由CT确定的GTVN(GTVN-CT)与病理一致,19例基于PET-CT的GTVN(GTVN-PET-CT)与病理相符。对照淋巴结病理结果,PET-CT改变了15例由CT确定的GTVN和其中10例的CTVN。PET-CT导致GTV缩小(GTVN-PET-CTGTVN- CT的12例共涉及22组淋巴结,其中9例CTVN亦扩大。GTVN-PET-CT>GTVN-CT的亚组分析显示,PET-CT确定的淋巴结GTV准确率高于CT(67%:25%,P=0.041)。结论PET-CT在诊断淋巴结转移中的优势使之可作为优化和确定食管癌淋巴结放疗靶区的有用工具。     

Utility of 18F-fluorodeoxyglucose positron emission tomography in the preoperative staging of squamous cell carcinoma of the oropharynx.

BACKGROUND: 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been reported to be superior to computed tomography (CT)/magnetic resonance imaging (MRI) in the evaluation of head and neck cancers, but little is known about its usefulness in oropharyngeal squamous cell carcinoma (SCC). We therefore compared FDG PET and CT/MRI in the preoperative staging of previously untreated oropharyngeal SCC. METHODS: Thirty-two consecutive patients with oropharyngeal SCC underwent FDG PET and CT/MRI before surgery. Each method was interpreted separately to assess primary tumor and cervical node status. Their sensitivity and specificity were compared relative to histopathologic analysis. RESULTS: Histopathology revealed metastases in 29 of 39 dissected neck sides and in 47 of 163 dissected cervical levels. FDG PET had higher sensitivities than CT/MRI for primary tumor detection (25/32 vs. 30/32, P=0.063) and for identification of cervical metastases on neck side (22/29 vs. 28/29, P<0.05) and level-by-level (37/47 vs. 45/47, P<0.05) bases. In contrast, the specificity of the two methods did not differ significantly (P>0.5). FDG PET correctly interpreted the false-negative results of CT/MRI in 6 of 7 primary tumors and 8 of 10 cervical levels. CONCLUSIONS: The improved preoperative staging of FDG PET may help in planning treatment, but its accuracy is insufficient to replace pathologic staging based on neck dissection.     

18F-FDG PET/CT在探查腹膜转移性肿瘤中的价值

目的:评价18F-FDG PET/CT探查腹膜转移瘤的价值。方法:39例有腹部原发恶性肿瘤手术史患者行PET/CT首次和延迟扫描,在PET/CT图像上记录病灶大小、分布,结果与常规CT比较。测量62个病灶和对照组32例腹部无病变患者的肠管SUVmax。所有病例经手术、病理、影像学和肿瘤标记物随访作出最后诊断。结果:最终确认39例中31例腹膜转移瘤,病灶均为结节状或沿腹膜条片状分布,多位于肝脏周围和盆腔腹膜,其他部位腹膜少见。PET/CT漏诊的4个病灶主要位于肝脏周围,1例因化疗不久病灶FDG低摄取而漏诊,因此敏感性为87.1%,特异性为87.1%。CT仅检出12例转移瘤。转移瘤SUVmax明显高于对照组肠管SUVmax(P=0.0000)。结论:18F-FDG PET/CT能够较CT更早、更多地检出腹膜转移瘤,病灶体积小、位于基础摄取较高的肝脏周围是漏诊主要原因,而结合原发肿瘤病史和肿瘤标记物检查有利于诊断。     

以DNA修复蛋白AGT为靶向的PET显像剂前体O^6-苄基鸟嘌呤类似物的体外初步生物评价

合成一系列O^6-苄基鸟嘌呤（O^6-BG）类似物，并且采用MTT法评价其体外对DNA修复蛋白AGT的抑制作用，探讨其作为潜在的正电子发射断层成像技术（PET）显像剂前体的可能性。以鸟嘌呤作为起始原料分别合成了O^6-BG及其类似物HMBG，MOBG，MOMOBG，BABP和PEG。采用MTT方法，通过测定合成产物增强HeLa细胞对1，3-双（2-氯乙基）亚硝基脲（BCNU）药物敏感性的强弱来评价其对AGT的抑制作用。合成产物对AGT抑制活性强弱排序为HMBG≥O^6-BG≥MOBG≥MOMBG，而BABP和PEG基本未表现出任何的AGT抑制活性。HMBG，MOBG和MOMBG具有良好的体外活性，其正电子核素标记物可能成为有前景的用于肿瘤AGT显像的PET显像剂。     

PET/CT显像在肺癌临床分期中的初步应用

目的:观察18F-FDG PET/CT显像和传统分期检查方法对肺癌分期和治疗后再分期的影响,以探讨其临床应用价值。方法:采用视觉分析和半定量分析相结合的方法,比较56例经病理检查确诊为肺癌患者的传统方法分期和PET/CT分期及治疗后再分期的符合率,以及对T、N和M分期准确性的差异。结果:PET/CT检查与传统方法对分期判断的符合率分别为92.9%(52/56)和75%(42/56)。对于T亚分期,PET/CT检查准确率为94.6%(53/56),CT检查准确率为82.1%(46/56),两者间无显著性差异(P>0.05);对N亚分期,PET/CT检查的准确率为92.9%(52/56),CT为73.2%(41/56),两者间有显著性差异(P<0.05);对M亚分期,PET/CT的准确率为96.4%(54/56),传统方法分期为89.3%(50/56),两者间无显著性差异(P>0.05)。PET/CT检查使TNM分期改变者13例,达23.2%,其中分期升高9例,下降4例,7例肺癌患者的治疗计划发生改变。结论:18F-FDG PET/CT可提高肺癌的分期和再分期的准确率,这有利于更准确地制订治疗方案,预测预后。     

FDG PET-CT标准摄取值用于非小细胞肺癌复发的预测价值

目的 探讨非小细胞肺癌(NSCLC)患者治疗前后FDG PET-CT的标准摄取值(SUV)及其变化在预测复发和转移中的作用.方法 48例Ⅲ期NSCLC患者治疗前后均行全身PET-CT检查,并计算出肺部肿瘤病灶感兴趣区的最高标准摄取值(SUVmax),治疗前后SUVmax的变化用ASUV来衡量.结果 最后入组45例,中位随访22.5个月,24例出现局部或区域复发、转移,21例无复发、转移.出现局部或区域复发、转移组治疗前和后SUVmax分别为12.30±3.17和5.35±2.29,无复发、转移组治疗前和后的分别为8.46±3.00和2.82±0.63,前者的SUVmax均高于后者(t前=4.15,P前＜0.01;t后=4.88,P后＜＜0.01).治疗前后SUVmax变化百分率两组间差异无统计学意义(t=1.99,P＞0.05).治疗前SUVmax=9.0时,对复发和转移预测的敏感性、特异性、阳性预测值、阴性预测值分别为92%、62%、73%、87%;治疗后SUVmax=4.3时,对复发和转移的分别为71%、100%、100%、72%.结论 治疗前后SUVmax高者近期出现复发和转移的可能性较大,可较早预测NSCLC复发的高危人群.NSCLC患者治疗前后SUV值可能是与生存相关的重要预后因素.     

三种阈值下勾画非小细胞肺癌PET图像靶区及影响的研究

目的 比较不同阈值对18FDG PET-CT图像中非小细胞肺癌靶区勾画及放疗计划可能产生的影响.方法 选择CT图像上原发灶边界清楚的、呼吸动度≤5 mm的非小细胞肺癌8例,注射18FDG后1 h行PET扫描并以CT图像作衰减校正.以CT图像勾画的大体肿瘤体积(GTVCT)为标准,比较PET图像上用3种阈值条件[即肿瘤内最大像素值的42%(42%Imax(total))、本底平均像素值+肿瘤内最大像素值与本底平均像素值的差值的20%(Iback+20%Imax-back(max))和本底平均像素值+肿瘤内每层最大像素值与本底平均像素值的差值的20%(Iback+20%Imax-back(slice))]勾画的GTV(计为GTV42%、GTV20%max和GTV20%slice)与GTVCT差异及对GTVCT覆盖率的差异.以GTVCT、GTV42%、GTV20%max、GTV20%slice三维外放1 cm为计划靶体积,分别计为PTVCT、PTV42%、PTV20%max、PTV20%slice.对不同PTV设计三维适形放疗计划,并均给予靶区剂量66 Gy分33次6.6周完成.比较以不同PTV设计的计划中,PTVCT内接受＜95%处方剂量的体积(VPTV)及肺V20,并推算可能产生的TCP和肺NTCP的差异.结果 GTV42%、GTV20%max、GTV20%slice与GTVCT的中位体积差分别为-54.1%,-21.5%和5.3%,三者对GTVCT的覆盖率中位数分别为45.9%、78.0%和95.3%(F=57.50,P＜0.01).以不同PTV设计放疗计划时,PTV42%的中位VPTV为7.5%,由此可能导致TCP中位下降1%.PTV20%max和PTV20%slice的中位VPTV分别为1.3%和0.0%,其TCP与PTVCT的相似,与PTV42%的不同.三者的肺V20和肺NTCP与PTVCT的相似.结论 层面化阈值条件Iback+20%Imax-back(slice)可能是PET图像用于肺癌靶区勾画的较准确阈值,该阈值不依赖于预先由CT提供的肿瘤体积信息,可望用于伴有肺不张的非小细胞肺癌的靶区勾画.     

Synergistic inhibitory effects of interferon-alpha and 5-fluorouracil on meningioma cells in vitro

We have investigated the effects of interferon- (IFN-) and 5-fluorouracil (5-FU) on meningioma cells in two different culture systems, evaluated by the uptake of radiolabelled methionine. With both IFN- and 5-FU an inhibitory effect on the uptake of radiolabelled methionine by the meningioma cells was demonstrated, and we found a synergistic inhibitory effect with a combination of IFN- and 5-FU. To obtain a maximal inhibition of cell metabolism without causing cell toxicity, we were able to decrease the dose of 5-FU by simultaneously adding IFN-. Our results suggest that a combined treatment of IFN- and 5-FU may be a successful alternative for patients with inoperable meningiomas. A novel in vitro positron emission tomography technique was used for the study of metabolic changes in tumour cells caused by drug treatment, which is complementary to conventional cell culture techniques.     

Bupropion occupancy of the dopamine transporter is low during clinical treatment

RATIONALE: Bupropion is thought to treat major depression by blocking the dopamine transporter (DAT) because bupropion appears to have a selective affinity for the DAT. The validity of this mechanism has been questioned because the affinity of bupropion for the DAT is quite low. OBJECTIVE: To determine the occupancy of bupropion for the DAT during clinical treatment of patients with depression. METHODS: Positron emission tomography with [(11)C]-RTI32 was used to determine the striatal DAT binding potential (BP) of eight depressed patients before and during treatment with bupropion. BP is proportional to available receptor density (receptors not blocked by drug). Occupancy is the percent change in BP. Eight healthy subjects were similarly studied in a test-retest design. RESULTS: No significant difference in DAT BP was found after bupropion treatment in comparison to the test-retest data. The occupancy after bupropion treatment was 14% (confidence interval 6-22%) as compared to 7% in the test-retest condition. CONCLUSIONS: Bupropion treatment occupies less than 22% of DAT sites. This raises the question as to whether a DAT occupancy of less than 22% is therapeutic or whether there is another mechanism involved during treatment with bupropion.