PET评价骨转移瘤

肿瘤骨转移会产生顽固性骨痛和脊髓受压等严重并发症,并对分期、治疗和判断预后产生深远的影响,因而探测骨转移是制定治疗计划的重要部分。骨转移瘤发现频率因原发肿瘤的类型和所用检查手段不同而不同,虽然目前核素骨扫描是探测骨转移瘤最常用的手段,但其对骨转移瘤的诊断效能仍有一定限度。与99mTc-亚甲基二膦酸盐(99mTc-MDP)骨显像相比,18F-氟化钠(18F-NaF)和18F-氟代脱氧葡萄糖(18F-FDG) PET是分别从骨转移瘤产生的成骨反应和骨转移瘤本身的代谢活性角度进行评价的两种正电子示踪剂,结合PET的高度空间分辨率,特别是最近迅速应用于临床的PET-CT技术,使得正电子体层显像在全身骨骼恶性疾病评价上的准确性进一步提高。     

~(99m)Tc-MIBI显像鉴别乳腺肿物良、恶性及探测腋窝淋巴结转移

目的：探讨^99mTc-甲氧基异丁基异腈（MIBI）肿瘤阳性显像方法对鉴别诊断乳腺肿物良、恶性及探测乳腺癌腋窝淋巴结转移的临床价值。方法：对60例一侧乳腺单发可触及肿物的女性患，进行仰卧前位及俯卧左、右侧位^99mTc-MIBI肿瘤阳性显像。在10－20min早期相和90－120min延迟相中，观察双侧乳腺及双侧腋窝和锁骨上淋巴结区的放射性分布情况，并计算患乳病变区与相对应健侧的计数比值（T／NT）。所有病例均有病理结果对照。结果：^99mTc-MIBI肿瘤阳性显像鉴别诊断乳腺良、恶性病变的灵敏度为92．9％，特异性为90．6％，阳性预测值为89．7％，阴性预测值为93．5％，准确性为91．7％；诊断腋窝淋巴结转移的灵敏度为83．3％，特异性为86．1％，阳性预测值为80％，阴性预测值为88．6％，准确性为85％。结论：^99mTc-MIBI肿瘤阳性显像对于鉴别乳腺肿物的性质和探测腋窝淋巴结转移具有较高的诊断准确性，有一定的临床应用价值。     

99mTc-抗D-二聚体单抗对实验动物陈旧性血栓的放射免疫显像研究

目的研究^99Tc标记的抗D-二聚体单抗在陈旧性动脉血栓和静脉血栓靶向定位诊断中的应用。方法采用机械损伤血管内膜的方法复制家兔股动脉血栓和股静脉血栓模型，血栓形成后3d将^99Tc标记的抗D-二聚体单抗注入动物血管内，以放射免疫显像检测技术观察放射性核素在血流和血栓部位的分布。结果血栓处放射性^99Tc的分布较健侧明显增多，而单纯钳夹血管组及正常对照组未见局部放射性物质的堆积。注入^99Tc标记的单抗后，动物未见不良反应，主要脏器未见病理改变。结论^99Tc标记的抗D-二聚体单抗可以作为血栓导向示踪剂，用于陈旧性动脉血栓和静脉血栓的定位诊断。     

18F-氟脱氧葡萄糖PET-CT与99mc-亚甲基二膦酸盐骨显像诊断转移性骨肿瘤的对比研究

目的 探讨18F-氟脱氧葡萄糖(18F-FDG)PET-CT与唧99mTc-亚甲基二膦酸盐(99mTc-MDP)全身骨显像对转移性骨肿瘤的诊断价值.方法 93例经病理证实为恶性肿瘤的患者同时接受18F-FDG PET-CT和99mTc-MDP全身骨显像(时间间隔在1周之内),对比分析两种显像结果,骨转移的诊断通过随访2年,由病理、X射线片、CT或MRI检查结果综合决定.结果 93例恶性肿瘤患者中,经过2年随访或病理证实骨转移44例,其中18F-FDG PET-CT灵敏度、特异度和准确率分别为95.4%、91.8%和93.5%,99mTc-MDP全身骨显像分别为90.9%、63.3%和76.3%.18F-FDG PET-CT对转移性骨肿瘤诊断的灵敏度与99mTc-MDP全身骨显像相近,但特异度(t=2.53,P＜0.05)和准确率t=2.47,P＜0.05)均明显高于99mTc-MDP全身骨显像.结论 PET-CT对转移性骨肿瘤有较高的诊断价值.     

99Tcm-tetrofosmin在乳腺癌及其转移灶显像中的应用

99Tcm-tetrofosmin作为亲肿瘤显像剂,对乳腺癌原发病灶和腋窝淋巴结转移的诊断有良好的灵敏度、特异性和准确率,可应用于乳腺癌全身骨转移和术后复发的诊断,其应用于乳腺癌前哨淋巴结转移的诊断、作为P-糖蛋白功能显像剂和三维立体定位引导孔针型活检等领域有着良好的发展前景.99Tcm-tetrofosmin乳腺癌及转移灶显像可与其他乳腺癌检查方法相结合提高乳腺癌诊断的准确率.     

99Tcm-MIBI显像在头颈部恶性肿瘤中的应用

99Tcm-MIBI(99Tcm-sestamibi)作为亲肿瘤显像剂,对头颈部恶性肿瘤及其颈部淋巴结转移、邻近颅骨受累的诊断有较高的灵敏度、特异性和准确性,在头颈部肿瘤的诊断和分期等方面有良好的应用前景.     

^99Tc^m—tetrofosmin在乳腺癌及其转移灶显像中的应用

^99Tc^m-tetrofosmin作为亲肿瘤显像剂,对乳腺癌原发病灶和腋窝淋巴结转移的诊断有良好的灵敏度,特异性和准确率,可应用于乳腺癌全身骨转移和术后复发的诊断,其应用于乳腺癌前哨淋巴结转移的诊断、作为P－糖蛋白功能显像剂和三维立体定位引导孔针型活检等领域有着良好的发展前景。^99Tc^m-tetrofosmin乳腺癌及转移灶显像可与其他乳腺癌检查方法相结合提高乳腺癌诊断的准确率。     

^99Tc^m-MIBI显像在头颈部恶性肿瘤中的应用

^99Tc^m-MIBI(^99Tc^m-sestamibi)作为亲肿瘤显像剂，对头颈部恶性肿瘤及其颈部淋巴结转移、邻近颅骨受累的诊断有较高的灵敏度、特异性和准确性，在头颈部肿瘤的诊断和分期等方面有良好的应用前景。     

99mTc-葡糖二酸显像剂的研究进展

葡糖二酸(GLA)是一种六碳二元羧酸盐的葡萄糖类似物,是葡萄糖在生物体内代谢的产物之一,存在于组织和体液中,可被99mTc标记。本文论述了GLA的制备、99mTc-GLA药盒的制备以及99mTc-GLA在心肌梗死显像和肿瘤显像中的研究进展。现有的研究结果表明,99mTc-GLA在诊断心肌梗死和某些肿瘤(如乳腺癌)表现了良好的性质,因此是一种很有应用前景和研究价值的显像剂。     

99mTc-枸橼酸盐显像鉴别骨转移癌与良性退行性骨病变

目的 探讨99mTc-枸橼酸盐(99mTc-citrate)显像在骨转移癌与良性退行性骨病鉴别诊断中的价值.方法 对99mTc-亚甲基二膦酸盐(99mTc-MDP)骨显像阳性患者39例(92个病灶)在显像后的2～7 d内行99mTc-citrate显像,并分别进行定性及半定量分析,所有患者的临床诊断均经病理学、影像学、临床随访等证实.结果 定性分析:23例(48个病灶)骨转移癌患者的99mTc-citrate显像示72.92%病灶(35/48)呈异常浓聚;16例良性退行性骨病变者99mTc-citrate显像示88.64%病灶(39/44)无异常浓聚.半定量分析:99mTc-citrate显像示48个骨转移灶的病灶与健侧放射性摄取比(RUR)=1.47±0.42,44个良性退行性骨病灶RUR=1.09±0.38,两者相比差异有显著性(t=2.887,P＜0.01);而99mTc-MDP显像示48个骨转移灶RUR=1.96±0.25,44个良性退行性骨病灶RUR=1.87±0.21,差异无显著性(t=1.178,P＞0.20).结论 对99mTc-MDP骨显像阳性患者,99mTc-citrate显像在鉴别骨转移癌和良性退行性骨病中具有一定价值.     

Tc-99m MIBI imaging in malignant fibrous histiocytoma

The authors report a case of malignant fibrous histiocytoma of the left forearm demonstrated by Tc-99m MIBI imaging. The tumor originated in the soft tissue of the forearm; no obvious bone invasion or metastasis was detected scintigraphically or radiologically.     

"Double imaging" for the diagnostic work-up of alveolar soft part sarcoma with Tc-99m MIBI

The authors report a case of alveolar soft-part sarcoma with lung metastases demonstrated by "double imaging" with Tc-99m HDP and Tc-99m MIBI. The tumor originated in the soft tissue with direct invasion to the right scapula, which was hypoactive on bone scan and hyperactive on Tc-99m MIBI images. A focus of dense accumulation of Tc-99m MIBI in the lungs, suggesting metastasis was also demonstrated.     

Targeted molecular imaging in oncology

Improvement of scintigraphic tumor imaging is extensively determined by the development of more tumor specific radiopharmaceuticals. Thus, to improve the differential diagnosis, prognosis, planning and monitoring of cancer treatment, several functional pharmaceuticals have been developed. Application of molecular targets for cancer imaging, therapy and prevention using generator-produced isotopes is the major focus of ongoing research projects. Radionuclide imaging modalities (positron emission tomography, PET; single photon emission computed tomography, SPECT) are diagnostic cross-sectional imaging techniques that map the location and concentration of radionuclide-labeled radiotracers. 99mTc- and 68Ga-labeled agents using ethylenedicysteine (EC) as a chelator were synthesized and their potential uses to assess tumor targets were evaluated. 99mTc (t1/2 = 6 hr, 140 keV) is used for SPECT and 68Ga (t1/2 = 68 min, 511 keV) for PET. Molecular targets labeled with Tc-99m and Ga-68 can be utilized for prediction of therapeutic response, monitoring tumor response to treatment and differential diagnosis. Molecular targets for oncological research in (1) cell apoptosis, (2) gene and nucleic acid-based approach, (3) angiogenesis (4) tumor hypoxia, and (5) metabolic imaging are discussed. Numerous imaging ligands in these categories have been developed and evaluated in animals and humans. Molecular targets were imaged and their potential to redirect optimal cancer diagnosis and therapeutics were demonstrated.     

Radiolabeled L-lysine for tumor imaging

RATIONALE AND OBJECTIVES: The aims of this study were to label the versatile amino acid l-lysine with (99m)Tc using 2,3-dimercapto-succinic acid (DMSA) as a chelator, and to assess its tumor imaging feasibility under in vivo and in vitro conditions, and finally to determine the subcellular biodistribution of this radiopharmaceutical. MATERIALS AND METHODS: DMSA-l-lysine was chemically synthesized and labeled with sodium pertechnetate. Nuclear magnetic resonance (NMR) and mass spectral analysis of DMSA-l-lysine were conducted. Radiochemical purity was determined by thin-layer chromatography (TLC) and paper chromatography. Cellular uptake, competition and subcellular localization studies were performed in rat breast cancer cells (13762). In vivo studies of planar imaging and biodistribution studies were performed on female Fischer 344 rats. Medical Internal Radiation Dose (MIRD) dosimetry estimates were calculated. RESULTS: Radiochemical purity (determined by radio-TLC and high-performance liquid chromatography) of these compounds was >95%. (99m)Tc-DMSA-l-lysine showed good uptake in in vitro cell culture assays and uptake was reduced in competition studies. (99m)Tc-DMSA-l-lysine accumulates in the nucleus as much as in the cytoplasm and it was also shown that accumulation of the (99m)Tc-DMSA-l-lysine in the nucleus increases as a function of a time. There was an increase in tumor-to-blood and tumor-to-muscle count density ratios. Tumor/background ratios were 5.75 at 1 hour and 6.87 at 2 hours. In vivo tissue distribution studies revealed that radiation dosimetry of blood-forming organs were within radiation dose limits. CONCLUSION: DMSA-l-lysine kits can be labeled with (99m)Tc easily and efficiently, with high radiochemical purity and cost-effectiveness. In vitro cellular uptake and scintigraphic imaging studies demonstrated the pharmacokinetic distribution and feasibility of using (99m)Tc-DMSA-l-lysine for tumor imaging.     

Radiosynthesis,molecular modeling studies and biological evaluation of 99mTc-Ifosfamide complex as a novel probe for solid tumor imaging

Purpose: Ifosfamide as a chemotherapeutic drug is used for the treatment of different cancer types. The purpose of this study is the preparation of ^99mTc-ifosfamide complex to be evaluated as a potential candidate for tumor imaging.

Materials and methods: The radiolabeling of ifosfamide with technetium-99m was carried out by mixing 4mg ifosfamide and 5?μg of SnCl₂.2H₂O with 400 MBq Na^99mTcO₄ at pH 9 for 30?min at room temperature. Computer simulation studies were performed using Accelrys Discovery Studio 2.5 operating system to illustrate the interaction of ifosfamide and ^99mTc-ifosfamide complexes with DNA. The in-vivo biodistribution of ^99mTc-ifosfamide was studied in tumor-bearing Albino mice.

Results: A new ^99mTc-ifosfamide complex was synthesized with a good radiochemical yield of 90.3?±?2.1% under the optimized conditions and exhibited in-vitro stability up to 2?h. Biodistribution studies showed good uptake in tumor site and high uptake in tumor site with T/NT ～3 after 60?min post-injection. Besides, the molecular docking study confirmed that the complexation of ifosfamide with technetium-99m does not abolish its binding to the target receptor.

Conclusion: These promising results afford a new radiopharmaceutical that could be used as a potential tumor imaging     

PET and planar imaging of tumor hypoxia with labeled metronidazole

RATIONALE AND OBJECTIVES: This study was aimed to develop 99mTc- and 68Ga-labeled metronidazole (MN) using ethylenedicysteine (EC) as a chelator and evaluate their potential use to assess tumor hypoxia. MATERIALS AND METHODS: EC-MN was labeled with 99mTc in the presence of tin (II) chloride. Labeling EC-MN with 68Ga was achieved by adding 68GaCl3 (2 mCi with 3.4 microg cold GaCl3). In vitro cellular uptakes of 99mTc- and 68Ga-EC-MN were obtained in various types of tumor cells at 0.5-4 hours. Tissue distribution and PET imaging of 99mTc and 68Ga-EC-MN were evaluated in breast tumor-bearing rats at 0.5-4 hours. Tumor oxygen tension was measured using an oxygen probe. RESULTS: There were similar cellular uptakes (2-10%) between 99mTc- and 68Ga-EC-MN at 0.5-4 hours. In vivo biodistribution of 99mTc- and 68Ga-EC-MN in breast tumor-bearing rats showed increased tumor-to-blood and tumor-to-muscle count density ratios as a function of time. Positron emission tomography images confirmed that the tumors could be visualized clearly with 68Ga-EC-MN. Oxygen tension in tumor tissue was determined to be 6-10 mm Hg compared with 40-50 mm Hg in normal muscle tissue. CONCLUSIONS: The results indicated that it is feasible to use 99mTc- and 68Ga-EC-MN for assessment of tumor hypoxia. These agents may be useful in selecting and evaluating cancer therapy.     

99Tcm-MIBI显像对肿瘤多药耐药检测的应用

MDR(多药耐药)是目前肿瘤化疗失败的主要原因,对MDR的检测可以帮助化疗决策的制定,从而使肿瘤患者得到更有效的治疗。99Tcm-MIBI(99Tcm-甲氧基异丁基异腈)是mdr1基因编码的P-gp(P-糖蛋白)和MRP(多药耐药相关蛋白)的转运底物,肿瘤细胞内99Tcm-MIBI摄取减低表明其P-gp的高表达,并与MRP的表达相关。因此,99Tcm-MIBI显像可在治疗前预测对化疗的反应,并为选择更有效的化疗策略提供依据。99m     

Synthesis,characterization, radiolabeling and biodistribution of a novel cyclohexane dioxime derivative as a potential candidate for tumor imaging

Purpose: Dioxime derivative is reported to exhibit high affinity towards tumor cells. The objective of the present study is to synthesize a new dioxime derivative to be labeled with technetium-99m for using as a solid tumor marker.

Materials and methods: ((2E,2′,3E,3′)-3,3′-(cyclohexane-1,2-diylbis (azanylylidene)) bis-(butan-2-one)dioxime) was synthesized by condensation of Butan-2,3-dione monooxime and diaminocyclohexane and labeled with ^99mTc. The in-vivo distribution of the agent was studied by carrying out biodistribution in tumor bearing Albino mice.

Results: A new cyclohexane dioxime derivative was synthesized with a good yield of 93?±?2% and its complexation with ^99mTc was prepared with 85?±?4% radiochemical yield under the optimized conditions and the preparation exhibited in-vitro stability up to 6?h. Biodistribution studies showed high uptake in tumor cells with T/NT (target to non-target ratio)?=?3.4?±?0.2 after 0.5?h post injection.

Conclusion: As a result of biodistribution studies, the newly synthesized cyclohexane dioxime derivative showed its good uptake in tumor cells, which affords a potential radiopharmaceutical that could be used as a good tumor imaging agent.     

恶性骨肿瘤多药耐药的99Tcm-MIBI体层显像研究

大多数肿瘤都有多药耐药-1(MDR-1)基因的过度表达,其表达产物P-糖蛋白(P-gp)在肿瘤的耐药机制中起着关键作用,对P-gp表达的预测在化疗中至关重要,99Tcm-甲氧基异丁基异腈(99Tcm-MIBI)转运分析可作为探测低水平的P-gp表达和定量评价调节转运的敏感指标,指导应用调节剂改善化疗效果.