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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Five normal rats, 14 rats bearing the Rous sarcoma intrarenally, and four rats with DMBA-induced mammary carcinomas were imaged by dynamic (18F)-2-fluoro-2-deoxy-D-glucose ((18F)FDG) scintigraphy and (99mTc)DTPA renography. The brain, heart, liver, kidneys, and tumor were selected as regions of interest (ROI) for time activity curves; exponential functions were fitted to the decay-corrected curves, which yielded biologic half-lives of (18F)FDG in the ROI. It was found that all organs ROI's exhibited average elimination of activity, whereas activity accumulated in the tumor ROI for the duration of the study (5 h). The (99mTc)DTPA renographies showed that the excretory function in kidneys bearing the Rous sarcoma is severely impaired. This study shows that small laboratory animals can be successfully scintigraphied with a conventional gamma camera using (18F)FDG and that the pharmacokinetics of this radiopharmaceutical may be evaluated.
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PMID:Dynamic (18F)-2-fluoro-2-deoxy-D-glucose (FDG) scintigraphy of normal and tumor-bearing rats. 302 Jun 54

Differences in the uptake of (18F)-2-fluoro-2-deoxy-D-glucose ((18F)FDG) in various normal organs and the Rous sarcoma of fasted and unfasted rats were studied at 5, 15, 30, 60, and 120 minutes after i.v. injection. The uptake of (18F)FDG in the tumor, spleen, and testis increased for 120 minutes, while uptake in the other organs was either level (brain, heart, white fat) or cleared off. The uptake was higher in the tumor than in the normal organs. The fraction of viable tumor tissue as measured morphometrically correlated intraindividually with the uptake of (18F)FDG--an increase of 1% of vital tumor corresponded to a 1.01-fold increase in tumor uptake of (18F)FDG. The nutritional state was of importance for the uptake of (18F)FDG into the heart, testis and brown fat. (18F)FDG is taken quantitatively up by the viable parts of the Rous tumor; this may make it possible to follow the response of treatment in individual tumors also in man with (18F)FDG and positron emission tomography (PET).
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PMID:Organ and tumor distribution of (18F)-2-fluoro-2-deoxy-D-glucose in fasting and non-fasting rats. 303 5

Using 19-fluorine (19F) as nuclear magnetic resonance (NMR) signal probe and 2-fluoro-2-deoxy-D-glucose (2-FDG) as metabolic probe, one dimensional "imaging" (metabolite mapping) of pathway specific glucose metabolism in the pentose monophosphate shunt (PMS) and aldose reductase sorbitol (ARS) pathways were performed in situ in rat brain utilizing one dimensional rotating frame zeugmatography. Normal brain showed highest PMS activities in the brainstem consonant with known spatially heterogeneous concentration of glucose-6-phosphate dehydrogenase, the rate limiting enzyme for the PMS. The brain harboring sufficiently large gliosarcoma in the cerebrum showed a higher PMS/ARS area ratio indicating higher PMS activities in tumor which was localized by zeugmatography. The present study demonstrated the feasibility of studying regional glucose metabolism in the PMS and ARS utilizing 2-FDG.
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PMID:Heterogeneity of regional cerebral glucose metabolism demonstrated in situ in rat brain by 19F NMR rotating frame zeugmatography: one dimensional chemical shift imaging of normal and gliosarcoma implanted brain. 311 61

Cerebral necrosis after radiotherapy for brain tumors is being recognized as a problem more common than previously estimated. Distinction between this iatrogenic complication and tumor recurrence cannot be made by either CT or MR imaging. By using positron emission tomography (PET) with 18F-deoxyglucose (FDG) we were able to reach a diagnosis of radiation necrosis, later verified, in 10 of 95 patients referred for the purpose of differentiating tumor recurrence from necrosis. The critical PET-FDG feature was focal hypometabolism in the area of necrosis, which contrasted with the hypermetabolism associated with the residual/recurrent tumor. In addition, four cases of cerebral necrosis after supraophthalmic, intraarterial chemotherapy (BCNU) were studied with the PET-FDG method. The area of chemotherapy damage was also characterized by marked hypometabolism. Histology revealed both similarities and differences between radio- and chemonecrosis.
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PMID:Cerebral necrosis after radiotherapy and/or intraarterial chemotherapy for brain tumors: PET and neuropathologic studies. 325 19

Patients with lymphomas are conventionally imaged with [67Ga]citrate for tumor detection and determination of dissemination. Fluorine-18-2-fluoro-2-deoxy-D-glucose [( 18F]FDG) is a radiopharmaceutical that accumulates into tissues where glucose utilization is enhanced, such as tumors. Six cancer patients (five non-Hodgkin's lymphomas, one endodermal retroperitoneal sinus carcinoma) were imaged with [18F]FDG and [67Ga]citrate whole-body scintigraphies in order to compare the sensitivities of these two tumor imaging radiopharmaceuticals. Among the five untreated lymphoma patients, two 67Ga scans and four [18F]FDG scans were positive; in the patient with the retroperitoneal carcinoma who had a positive [18F]FDG scan before treatment, both scans were negative after treatment. Fluorine-18 FDG may be a more sensitive tumor-detecting radiopharmaceutical for non-Hodgkin's lymphoma than [67Ga]citrate.
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PMID:Comparison of fluorine-18-2-fluorodeoxyglucose and gallium-67 citrate imaging for detection of lymphoma. 346 32

A patient with a benign chromophobe adenoma, who had incomplete surgical removal followed by radiotherapy, continued to have epileptic seizures up to two or three times a day. She was studied with positron emission tomography using 18F-2-deoxyglucose (FDG). This technique showed a high level of glucose utilization in the area of the operated tumor but also clear reduction of glucose utilization in the left medial temporal region adjacent to the sella and the scar tissue from the neoplasm. This area of reduced glucose utilization corresponded well to the same finding observed in other patients with complex partial epilepsy. A left temporal anterior lobectomy was carried out followed by improved control of the epilepsy. Positron emission tomography using FDG, together with electrophysiological examinations, may assist in the management of epilepsy related to pituitary tumors.
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PMID:Pituitary adenoma with seizures: PET demonstration of reduced glucose utilization in the medial temporal lobe. 348 98

Nine radiation-treated brain tumor patients were studied by positron emission tomography (PET) in an attempt to differentiate tumor recurrence from radiation necrosis. Rubidium-82 was used to define the region of absent or disturbed blood-brain barrier and [18F]2-fluoro-2-deoxy-D-glucose ([18F]FDG) was used to evaluate the metabolic state of the brain. By comparing glucose utilization in the pathologic region with utilization in the adjacent tissue, a diagnosis of recurrent tumor (increased [18F]FDG accumulation) or necrosis (decreased FDG accumulation) was made. In the seven patients who underwent surgery the PET diagnosis was confirmed by histologic examination of resected tissue. The two patients who did not undergo surgery have had a clinical course consistent with the PET diagnosis of necrosis. Dynamic 82Rb imaging showed that the rate of 82Rb accumulation was greater in tumor than in normal brain. However, this finding alone did not differentiate tumor from necrosis, as some necrotic tissue also showed high rates of 82Rb accumulation, and washout kinetics were similarly nonspecific. The differentiation of radiation necrosis from tumor recurrence is reliably achieved by [18F]FDG PET examination and is aided by information obtained from a 82Rb PET study done immediately prior to the [18F]FDG injection.
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PMID:Differentiation of cerebral radiation necrosis from tumor recurrence by [18F]FDG and 82Rb positron emission tomography. 349 66

Seventeen patients with intracranial meningiomas were studied with positron emission tomography and fluorine-18-2-fluorodeoxyglucose (PET-FDG) to assess the glucose utilization of these tumors. Four meningiomas followed for 3-5 years after PET-FDG and surgery showed no evidence of recurrence. These tumors had significantly lower glucose utilization rates (1.9 mg/dl/min +/- 1.0) than 11 recurrent or regrowing meningiomas (4.5 mg/dl/min +/- 1.96) (P less than .01). The glucose metabolic rates of meningiomas correlated with tumor growth, as estimated from changes in tumor size on repeated computed tomographic scans. Histopathologically, a syncytial (atypical) meningioma had the highest glucose utilization rate, followed by a papillary meningioma and an angioblastic meningioma. Individual transitional and syncytial (typical) meningiomas showed marked differences in glucose metabolism despite similar microscopic appearance. Glucose utilization rate appears to be at least as reliable as histologic classification and other proposed criteria for predicting the behavior and recurrence of intracranial meningiomas.
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PMID:Glucose utilization by intracranial meningiomas as an index of tumor aggressivity and probability of recurrence: a PET study. 349 26

We studied cerebellar metabolism in 118 subjects including young and elderly controls and patients suffering from stroke, supratentorial brain tumor and Alzheimer's disease using fluorine-18 fluorodeoxyglucose ([18F]FDG) and position emission tomography (PET). Alzheimer's disease and normal aging did not alter mean cerebellar metabolism. In stroke and tumor mean cerebellar metabolism was lower in the hemisphere contralateral to the supratentorial lesion. In tumor bilaterally significant reductions in absolute cerebellar metabolism also were noted, unlike stroke. Primary sensory stimulation did not alter absolute or relative cerebellar metabolism. These results show that absolute and relative values for cerebellar metabolism vary depending on the process under study. Thus analysis schemes employing normalization of regional metabolic data to cerebellar values may be subject to error.
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PMID:Cerebellar glucose consumption in normal and pathologic states using fluorine-FDG and PET. 349 90

Computerized dynamic gamma camera scintigraphy was performed with [18F]2-fluoro-2-deoxy-D-glucose [( 18F]FDG) on 10 patients with different cancers; tumor perfusion was evaluated in four patients with 99mTc-DPD. All tumors were visible in the [18F]FDG scans with tumor-to-tissue image contrast ratios of 1.2-11.7. Tumor perfusion exceeded that of the surrounding normal tissue in three of the four patients studied. Tumor-to-normal tissue [18F]FDG ratios were plotted as a function of the time. Two types of curves emerged: curves showing a linear increase in the ratio and curves showing a constant value for the ratio. These studies show that [18F]FDG can be used for clinical tumor imaging with a gamma camera, and that there appears to be biological differences in tumor uptake of [18F]FDG.
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PMID:Scintigraphy with [18F]2-fluoro-2-deoxy-D-glucose of cancer patients. 377 Dec 40


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