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Tchirikov M, Tchirikov M, Buchert R, Wilke F, Brenner W. Glucose uptake in the placenta, fetal brain, heart and liver related to blood flow redistribution during acute hypoxia. J Obstet Gynaecol Res 2011; 37:979-85. [PMID: 21463426 DOI: 10.1111/j.1447-0756.2010.01468.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM We used positron emission tomography (PET) with radioactive glucose (F-18-Fluor-Deoxglucose [FDG]) to investigate whether acute maternal hypoxemia causes alterations of glucose uptake of fetal organs and the placenta. MATERIAL AND METHODS Investigation was performed under normal conditions and acute hypoxemia in 16 fetal sheep between 108 and 130 days of gestation. Maternal sheep were ventilated with 1.0-1.5% isoflurane/O(2) /N(2) O during whole scanning procedure. Acute hypoxia was induced by reducing O(2) in a ventilated gas mixture to achieve maternal arterial O(2) saturation at a constant level of about 75% baseline. Doppler ultrasound blood flow measurements were performed in the ductus venosus (DV), umbilical artery (UA) and vein (UV). Fetal blood samples were taken by cordocentesis of UV. Dynamic positron emission tomography combined with computed tomography (PET-CT) scans of fetuses were acquired over 60 min after intravenous injection of 300 MBq FDG in the mother. Relative FDG uptake in the fetal brain, heart, and liver was determined on summed images from 40-60 min using manually defined volumes of interest (VOI) normalized to mean FDG uptake in placentomes. RESULTS Placental blood perfusion reduced significantly from 416.5 ± 116.4 mL/min to 253.5 ± 170.5 mL/min (mean ± SD) during hypoxia. Placental blood supply to the liver decreased from 79.5 ± 14% to 41.1% (P = 0.0001), while DV/UV ratio increased. FDG uptake of the placenta was not changed during hypoxia. Relative FDG uptake in the fetal heart was strongly increased under hypoxia (P = 0.019), whereas it did not differ in the fetal brain and liver. CONCLUSION Fetal hypoxia is associated with decreased placental perfusion and liver blood supply. However, glucose uptake was not significantly decreased in the placenta and liver.
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Affiliation(s)
- Michael Tchirikov
- Department of Obstetrics and Prenatal Medicine, University Medical Center Mainz, Mainz, Germany.
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Inoue K, Moriya E, Suzuki T, Ohnuki Y, Sato T, Kitamura H, Sasaki T, Fukushi M, Moriyama N, Fujii H. The usefulness of fully three-dimensional OSEM algorithm on lymph node metastases from lung cancer with 18F-FDG PET/CT. Ann Nucl Med 2011; 25:277-87. [DOI: 10.1007/s12149-010-0462-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 12/07/2010] [Indexed: 11/29/2022]
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Aide N, Kinross K, Cullinane C, Roselt P, Waldeck K, Neels O, Dorow D, McArthur G, Hicks RJ. 18F-FLT PET as a Surrogate Marker of Drug Efficacy During mTOR Inhibition by Everolimus in a Preclinical Cisplatin-Resistant Ovarian Tumor Model. J Nucl Med 2010; 51:1559-64. [DOI: 10.2967/jnumed.109.073288] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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Denoyer D, Greguric I, Roselt P, Neels OC, Aide N, Taylor SR, Katsifis A, Dorow DS, Hicks RJ. High-contrast PET of melanoma using (18)F-MEL050, a selective probe for melanin with predominantly renal clearance. J Nucl Med 2010; 51:441-7. [PMID: 20150254 DOI: 10.2967/jnumed.109.070060] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The aim of this study was to evaluate the novel probe (18)F-6-fluoro-N-[2-(diethylamino)ethyl] pyridine-3-carboxamide ((18)F-MEL050) for the imaging of primary and metastatic melanoma. METHODS PET using (18)F-MEL050 was performed in murine models of melanoma. The specificity of (18)F-MEL050 was studied by comparing its accumulation in pigmented B16-F0 allograft tumors with that of human amelanotic A375 xenografts using PET and high-resolution autoradiography. (18)F-MEL050 PET results were compared with (18)F-FDG PET, the current standard in melanoma molecular imaging. To test the ability of (18)F-MEL050 to assess the metastatic spread of melanoma, a murine model of lung metastasis was imaged by PET/CT, and results correlated with physical assessment of tumor burden in the lungs. RESULTS In pigmented B16-F0 grafts, (18)F-MEL050 PET yielded a tumor-to-background ratio of approximately 20:1 at 1 h and greater than 50:1 at 2 and 3 h. In the B16-F0 melanoma allograft model, tumor-to-background ratio was more than 9-fold higher for (18)F-MEL050 than for (18)F-FDG (50.9 +/- 6.9 vs. 5.8 +/- 0.5). No uptake was observed in the amelanotic melanoma xenografts. Intense uptake of (18)F-MEL050 was evident in metastatic lesions in the lungs of B16-BL6 tumor-bearing mice on PET at 2 h after tracer injection, with high concordance between (18)F-MEL050 accumulation on PET/CT and tumor burden determined at necroscopy. CONCLUSION (18)F-MEL050 has a rapid tumor uptake and high retention with specificity for melanin, suggesting great potential for noninvasive clinical evaluation of suspected metastatic melanoma.
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Affiliation(s)
- Delphine Denoyer
- Centre for Molecular Imaging and Translational Research Laboratory, Peter MacCallum Cancer Centre, Victoria, Australia
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Effect of variation in relaxation parameter value on LOR-RAMLA reconstruction of 18F-FDG PET studies. Nucl Med Commun 2010; 30:926-33. [PMID: 19574939 DOI: 10.1097/mnm.0b013e32832ed3cf] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE We tested the impact of different values of the relaxation parameter lambda (lambda) on contrast and noise in line-of-response row-action maximum likelihood algorithm (LOR-RAMLA) in 18F-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) imaging. METHODS Phantom studies were performed on a Gemini XL PET/CT scanner. The NEMA/IEC (National Electrical Manufacturers Association/International Electro technical Commission) torso phantom was used and acquisition data were reconstructed with lambda values ranging from 0.025 to 0.1. Quality of the reconstructed images was evaluated by contrast recovery coefficients and background variability values according to the NEMA NU 2-2001 procedures. RESULTS Contrast recovery coefficients and background variability increased significantly when lambda increased. The best noise-versus-resolution trade-off was obtained with lambda in the 0.04-0.06 range. For LOR-RAMLA reconstruction, the manufacturer allows a possible lambda choice from 0.025 to 0.1. We would not advise too small (0.025) or too large (0.1) lambda values which result in too smooth or too noisy images. CONCLUSION We determined optimal lambda values in LOR-RAMLA on a Gemini XL PET/CT scanner. Caution is needed when using lambda values out of that range.
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Sato H, Cho K, Fukushima Y, Shiiba M, Hakozaki K, Kiriyama T, Sakurai M, Kanaya K, Kumita SI. Validation of fast-RAMLA in clinical PET. Ann Nucl Med 2009; 22:869-76. [DOI: 10.1007/s12149-008-0196-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Accepted: 06/30/2008] [Indexed: 11/29/2022]
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Early evaluation of the effects of chemotherapy with longitudinal FDG small-animal PET in human testicular cancer xenografts: early flare response does not reflect refractory disease. Eur J Nucl Med Mol Imaging 2008; 36:396-405. [PMID: 19050878 DOI: 10.1007/s00259-008-0984-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 10/09/2008] [Indexed: 01/27/2023]
Abstract
AIM We aimed to evaluate the usefulness of FDG PET in the early prediction of the effects of chemotherapy on human testicular cancer xenografts. MATERIAL AND METHODS Nude rats bearing subcutaneous human embryonal carcinoma xenografts received either cisplatin (5 mg/kg) or saline serum. Small-animal PET studies were performed on days 0, 2, 4 and 7 and compared to immunochemistry studies, flow cytometry studies and hexokinase assays. RESULTS Cisplatin treatment resulted in biphasic FDG uptake evolution: a peak was observed on day 2, followed by a marked decrease on day 7 despite an insignificant change in tumour volume. Similarly, a peak in cyclin A immunostaining was observed on days 2 and 4), followed by a significant decrease on day 7. Flow cytometry showed that the cyclin A peak was not related to increased cell proliferation but was due to a transient S and G(2)/M cell cycle arrest. A marked increase in cell apoptosis was observed from day 2 to day 7. GLUT-1 showed a significant decrease on day 7. Macrophagic infiltrate remained stable except for an increase observed on day 7. In control tumours, continuous growth was observed, all immunostaining markers remaining stable over time. Hexokinase activity was significantly lower on day 7 in treated tumours than in controls. CONCLUSION FDG PET may be useful in the early evaluation of treatment in patients with testicular cancer. In our model, a very early increased [(18)F]-FDG uptake was related to a transient cell cycle arrest and early stage apoptosis but did not reveal refractory disease.
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Aide N, Labiche A, Herlin P, Paciencia M, Poulain L, Dutoit S, Montravers F, Gauduchon P, Chasle J. Usefulness of automatic quantification of immunochemical staining on whole tumor sections for correlation with oncological small animal PET studies: an example with cell proliferation, glucose transporter 1 and FDG. Mol Imaging Biol 2008; 10:237-44. [PMID: 18543043 DOI: 10.1007/s11307-008-0144-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 02/14/2008] [Accepted: 03/03/2008] [Indexed: 10/22/2022]
Abstract
AIM To highlight the use of automatic quantification of immunochemical staining on digitized images of whole tumor sections in preclinical positron emission tomography (PET) studies. MATERIALS AND METHODS Xenografted human testicular tumors (36) were imaged with 2-deoxy-2[F-18]fluoro-D: -glucose (FDG) small animal PET (SA-PET). Tumor cell proliferation and glucose transportation were assessed with cyclin A and Glut-1 immunostaining. Tumor slides were digitized and processed with PixCyt software enabling whole slide quantification, then compared with junior and senior pathologist manual scoring. Manual and automatic quantification results were correlated to FDG uptake. RESULTS For cyclin A, inter- and intra-observer agreement for manual scoring was 0.52 and 0.72 and concordance between senior pathologist and automatic quantification was 0.84. Correlations between Tumor/Background ratio and tumor cell proliferation assessed by automatic quantification, junior and senior pathologists were 0.75, 0.55, and 0.61, respectively. Correlation between Tumor/Background ratio and Glut-1 assessed by automatic quantification was 0.74. CONCLUSION Automatic quantification of immunostaining is a valuable tool to overcome inter- and intra-observer variability for correlation of cell proliferation or other markers with tumor tracer uptake.
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Affiliation(s)
- Nicolas Aide
- GRECAN, EA 1772, François Baclesse Comprehensive Cancer Center and Caen University, Caen, France.
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Ohno Y, Koyama H, Takenaka D, Nogami M, Maniwa Y, Nishimura Y, Ohbayashi C, Sugimura K. Dynamic MRI, dynamic multidetector-row computed tomography (MDCT), and coregistered 2-[fluorine-18]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET)/CT: Comparative study of capability for management of pulmonary nodules. J Magn Reson Imaging 2008; 27:1284-95. [DOI: 10.1002/jmri.21348] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Aide N, Louis MH, Dutoit S, Labiche A, Lemoisson E, Briand M, Nataf V, Poulain L, Gauduchon P, Talbot JN, Montravers F. Improvement of semi-quantitative small-animal PET data with recovery coefficients: A phantom and rat study. Nucl Med Commun 2007; 28:813-22. [PMID: 17728612 DOI: 10.1097/mnm.0b013e32822a0f37] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIM To evaluate the accuracy of semi-quantitative small-animal PET data, uncorrected for attenuation, and then of the same semi-quantitative data corrected by means of recovery coefficients (RCs) based on phantom studies. MATERIALS AND METHODS A phantom containing six fillable spheres (diameter range: 4.4-14 mm) was filled with an 18F-FDG solution (spheres/background activity=10.1, 5.1 and 2.5). RCs, defined as measured activity/expected activity, were calculated. Nude rats harbouring tumours (n=50) were imaged after injection of 18F-FDG and sacrificed. The standardized uptake value (SUV) in tumours was determined with small-animal PET and compared to ex-vivo counting (ex-vivo SUV). Small-animal PET SUVs were corrected with RCs based on the greatest tumour diameter. Tumour proliferation was assessed with cyclin A immunostaining and correlated to the SUV. RESULTS RCs ranged from 0.33 for the smallest sphere to 0.72 for the largest. A sigmoidal correlation was found between RCs and sphere diameters (r(2)=0.99). Small-animal PET SUVs were well correlated with ex-vivo SUVs (y=0.48x-0.2; r(2)=0.71) and the use of RCs based on the greatest tumour diameter significantly improved regression (y=0.84x-0.81; r(2)=0.77), except for tumours with important necrosis. Similar results were obtained without sacrificing animals, by using PET images to estimate tumour dimensions. RC-based corrections improved correlation between small-animal PET SUVs and tumour proliferation (uncorrected data: Rho=0.79; corrected data: Rho=0.83). CONCLUSION Recovery correction significantly improves both accuracy of small-animal PET semi-quantitative data in rat studies and their correlation with tumour proliferation, except for largely necrotic tumours.
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Affiliation(s)
- Nicolas Aide
- Groupement Régional d'Etudes sur le cancer Unité Bioticla, EA 1772, Université de Caen and Centre François Baclesse, Caen, France.
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Drever L, Roa W, McEwan A, Robinson D. Comparison of three image segmentation techniques for target volume delineation in positron emission tomography. J Appl Clin Med Phys 2007; 8:93-109. [PMID: 17592458 PMCID: PMC5722408 DOI: 10.1120/jacmp.v8i2.2367] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 11/28/2006] [Accepted: 12/31/1969] [Indexed: 11/23/2022] Open
Abstract
Incorporation of positron emission tomography (PET) data into radiotherapy planning is currently under investigation for numerous sites including lung, brain, head and neck, breast, and prostate. Accurate tumor-volume quantification is essential to the proper utilization of the unique information provided by PET. Unfortunately,target delineation within PET currently remains a largely unaddressed problem. We therefore examined the ability of three segmentation methods-thresholding, Sobel edge detection, and the watershed approach-to yield accurate delineation of PET target cross-sections. A phantom study employing well-defined cylindrical and spherical volumes and activity distributions provided an opportunity to assess the relative efficacy with which the three approaches could yield accurate target delineation in PET. Results revealed that threshold segmentation can accurately delineate target cross-sections, but that the Sobel and watershed techniques both consistently fail to correctly identify the size of experimental volumes. The usefulness of threshold-based segmentation is limited, however, by the dependence of the correct threshold (that which returns the correct area at each image slice) on target size.
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Affiliation(s)
- Laura Drever
- Department of Medical PhysicsBC Cancer AgencyVictoriaBritish ColumbiaCanada
| | - Wilson Roa
- Department of Radiation OncologyCross Cancer InstituteEdmontonAlbertaCanada
| | - Alexander McEwan
- Department of Oncologic ImagingCross Cancer InstituteEdmontonAlbertaCanada
| | - Don Robinson
- Department of Medical PhysicsCross Cancer InstituteEdmontonAlbertaCanada
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Ohno Y, Koyama H, Nogami M, Takenaka D, Yoshikawa T, Yoshimura M, Ohbayashi C, Sugimura K. STIR turbo SE MR imaging vs. coregistered FDG-PET/CT: Quantitative and qualitative assessment of N-stage in non-small-cell lung cancer patients. J Magn Reson Imaging 2007; 26:1071-80. [PMID: 17896365 DOI: 10.1002/jmri.21106] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To conduct a prospective comparison of the accuracy of short inversion time (TI) inversion-recovery (STIR) turbo spin-echo (SE) imaging and coregistered 2-[fluorine-18] fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) with computed tomography (CT) (coregistered FDG-PET/CT) to assess the N-stage in non-small-cell lung cancer (NSCLC) patients. MATERIALS AND METHODS A total of 115 consecutive NSCLC patients prospectively underwent CT, STIR turbo SE imaging, and FDG-PET, as well as surgical and pathological examinations. All STIR turbo SE images were obtained with a 0.9% saline phantom, which was placed alongside the chest wall of each patient, and coregistered FDG-PET/CTs were reconstructed using commercially available software. For quantitative assessments, the ratio of signal intensity (SI) of each lymph node to that of 0.9% saline phantom (lymph node-saline ratio [LSR]) and maximal standardized uptake value (SUV(max)) of each lymph node were calculated. Feasible threshold values were determined by using the receiver operating characteristic (ROC) curve-based positive test, and diagnostic capabilities of N-stage were compared by McNemar's test on a per patient basis. RESULTS When feasible, threshold values were adopted, quantitative sensitivity (90.1%) and accuracy (92.2%) of STIR turbo SE imaging were significantly higher than those of quantitative and qualitative sensitivities (76.7% and 74.4%) and accuracies (83.5% and 82.6%) of coregistered FDG-PET/CT on a per patient basis (P < 0.05). CONCLUSION STIR turbo SE imaging is at least as valid as coregistered FDG-PET/CT for quantitative and qualitative assessment of the N-stage for NSCLC patients.
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Affiliation(s)
- Yoshiharu Ohno
- Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan
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Dorow DS, Cullinane C, Conus N, Roselt P, Binns D, McCarthy TJ, McArthur GA, Hicks RJ. Multi-tracer small animal PET imaging of the tumour response to the novel pan-Erb-B inhibitor CI-1033. Eur J Nucl Med Mol Imaging 2006; 33:441-52. [PMID: 16450138 DOI: 10.1007/s00259-005-0039-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Accepted: 11/10/2005] [Indexed: 02/03/2023]
Abstract
PURPOSE This study was designed as "proof of concept" for a drug development model utilising multi-tracer serial small animal PET imaging to characterise tumour responses to molecularly targeted therapy. METHODS Mice bearing subcutaneous A431 human squamous carcinoma xenografts (n=6-8) were treated with the pan-Erb-B inhibitor CI-1033 or vehicle and imaged serially (days 0, 3 and 6 or 7) with [(18)F]fluorodeoxyglucose, [(18)F]fluoro-L: -thymidine, [(18)F]fluoro-azoazomycinarabinoside or [(18)F]fluoromisonidazole. Separate cohorts (n=3) were treated identically and tumours were assessed ex vivo for markers of glucose metabolism, proliferation and hypoxia. RESULTS During the study period, mean uptake of all PET tracers generally increased for control tumours compared to baseline. In contrast, tracer uptake into CI-1033-treated tumours decreased by 20-60% during treatment. Expression of the glucose transporter Glut-1 and cell cycle markers was unchanged or increased in control tumours and generally decreased with CI-1033 treatment, compared to baseline. Thymidine kinase activity was reduced in all tumours compared to baseline at day 3 but was sevenfold higher in control versus CI-1033-treated tumours by day 6 of treatment. Uptake of the hypoxia marker pimonidazole was stable in control tumours but was severely reduced following 7 days of CI-1033 treatment. CONCLUSION CI-1033 treatment significantly affects tumour metabolism, proliferation and hypoxia as determined by PET. The PET findings correlated well with ex vivo biomarkers for each of the cellular processes studied. These results confirm the utility of small animal PET for evaluation of the effectiveness of molecularly targeted therapies and simultaneously definition of specific cellular processes involved in the therapeutic response.
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Affiliation(s)
- Donna S Dorow
- Centre for Molecular Imaging, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
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Cullinane C, Dorow DS, Kansara M, Conus N, Binns D, Hicks RJ, Ashman LK, McArthur GA, Thomas DM. AnIn vivoTumor Model Exploiting Metabolic Response as a Biomarker for Targeted Drug Development. Cancer Res 2005; 65:9633-6. [PMID: 16266981 DOI: 10.1158/0008-5472.can-05-2285] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In vivo models that recapitulate oncogene-dependent tumorigenesis will greatly facilitate development of molecularly targeted anticancer therapies. We have developed a model based on activating mutations in c-KIT in gastrointestinal stromal tumors (GISTs). This model comprises murine tumors of FDC-P1 cell lines expressing c-KIT mutations that render the tumors either responsive (V560G) or resistant (D816V) to the small-molecule c-KIT inhibitor, imatinib. Clinically, GIST response to imatinib is associated with rapid reduction in fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET), preceding changes in conventional response criteria by several weeks. Using the FDC-P1 model in small animal PET, FDG uptake into tumors expressing the c-KIT V560G mutation was significantly reduced as early as 4 hours after imatinib treatment. In contrast, no change in FDG uptake was observed in resistant c-KIT D816V-expressing tumors after 48 hours of imatinib treatment. Consistent with the PET results, expression of the glucose transporter, GLUT1, was significantly reduced in V560G tumors at 4 hours, preceding changes in markers of proliferation by several hours. In vitro, imatinib treatment of V560G cells resulted in a reduction of glucose transporter numbers at the cell surface and decreased glucose uptake well before changes in cell viability. Notably, decreased ambient glucose concentrations enhanced the cytotoxic effect of imatinib. Taken together, these data account for the rapidity and significance of the PET response to imatinib and suggest that metabolic effects may contribute to imatinib cytotoxicity. Further, the FDC-P1 model represents a very useful paradigm for molecularly targeted drug development.
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Affiliation(s)
- Carleen Cullinane
- Sir Donald and Lady Trescowthick Laboratories and Center for Molecular Imaging, Peter MacCallum Cancer Center, Melbourn, Victoria, Australia
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Visvikis D, Griffiths D, Costa DC, Bomanji J, Ell PJ. Clinical evaluation of 2D versus 3D whole-body PET image quality using a dedicated BGO PET scanner. Eur J Nucl Med Mol Imaging 2005; 32:1050-6. [PMID: 15846487 DOI: 10.1007/s00259-005-1809-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2004] [Accepted: 03/03/2005] [Indexed: 11/28/2022]
Abstract
PURPOSE Three-dimensional positron emission tomography (3D PET) results in higher system sensitivity, with an associated increase in the detection of scatter and random coincidences. The objective of this work was to compare, from a clinical perspective, 3D and two-dimensional (2D) acquisitions in terms of whole-body (WB) PET image quality with a dedicated BGO PET system. METHODS 2D and 3D WB emission acquisitions were carried out in 70 patients. Variable acquisition parameters in terms of time of emission acquisition per axial field of view (aFOV) and slice overlap between sequential aFOVs were used during the 3D acquisitions. 3D and 2D images were reconstructed using FORE+WLS and OSEM respectively. Scatter correction was performed by convolution subtraction and a model-based scatter correction in 2D and 3D respectively. All WB images were attenuation corrected using segmented transmission scans. Images were blindly assessed by three observers for the presence of artefacts, confidence in lesion detection and overall image quality using a scoring system. RESULTS Statistically significant differences between 2D and 3D image quality were only obtained for 3D emission acquisitions of 3 min. No statistically significant differences were observed for image artefacts or lesion detectability scores. Image quality correlated significantly with patient weight for both modes of operation. Finally, no differences were seen in image artefact scores for the different axial slice overlaps considered, suggesting the use of five slice overlaps in 3D WB acquisitions. CONCLUSION 3D WB imaging using a dedicated BGO-based PET scanner offers similar image quality to that obtained in 2D considering similar overall times of acquisitions.
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Affiliation(s)
- D Visvikis
- U650 INSERM, Laboratoire de Traitement de l'Information Medicale (LaTIM), CHU Morvan, Brest, 29609, France.
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