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

The past decade has seen the identification of many clinical settings in the treatment of primary brain tumors in which information from fluorodeoxyglucose positron emission tomography (FDG-PET) might be useful, if not essential, to therapeutic formulation. FDG-PET is currently used at referral centers in the management of primary brain tumors. The clinical pattern of FDG-PET use was assessed and its value compared to other information sources in clinical decision making. The clinical records of 75 glioma patients who were evaluated by FDG-PET were reviewed. The range of circumstances in which FDG-PET was employed included: pretherapeutic baseline studies for monitoring the effect of a therapy (1% of all cases), mapping of hypermetabolic regions before surgery or biopsy (2%), mapping of hypermetabolic regions before radiotherapy (2%), postsurgical evaluation for residual tumor (2%), assessment of the malignancy of a mass as a substitute for biopsy (11%), and distinguishing between radiation necrosis and recurrent tumor (87%). Other sources of information that contributed to the therapeutic management of patients included: gadolinium-enhanced MRI, contrast-CT, and clinical findings.
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PMID:Impact of fluorodeoxyglucose positron emission tomography on the clinical management of patients with glioma. 887 74

The noninvasive staging of axillary lymph nodes for metastases is investigated in patients with breast cancer prior to surgery by positron emission tomography (PET) with fluorine-18-fluoro-2-deoxy-d-glucose (18F-FDG). In 124 patients with newly diagnosed breast cancer, whole-body PET was performed to determine the average differential uptake ratio (DUR) of 18F-FDG in the axillary lymph nodes. Results were correlated with the number of the dissected lymph nodes, size of the primary tumor, tumor type, tumor grade, estrogen and progesterone receptors, DNA ploidy, and the proportion of cells in the synthetic phase of the cell cycle (S-phase). In this prospective study of 124 patients with breast carcinoma, PET correctly categorized all 44 tumor-positive axillary lymph nodes, a sensitivity of 100%. Sixty tumor-negative axillary lymph nodes were negative by PET and 20 tumor-negative axillary lymph nodes were positive by PET. No false-negative PET findings were encountered. A weak correlation was found between DUR and tumor size as well as between DUR and the S-phase of the tumor. In patients with breast carcinoma, 18F-FDG PET can be of value in evaluating axillary lymph nodes for metastatic involvement prior to surgery. It is of particular importance that no false-negative PET findings were encountered, and axillary lymph node dissection might not be necessary in patients without axillary uptake by PET. The DUR of the positive axillary lymph nodes seems to bear a relationship with some of the purported prognostic parameters of the primary tumor.
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PMID:Prospective evaluation of fluorine-18 fluorodeoxyclucose positron emission tomography in breast cancer for staging of the axilla related to surgery and immunocytochemistry. 892 12

We report a case of high uptake of 11C-methionine (MET), 18F-FDG (FDG) and 201Tl-Cl (Tl) in brain radiation necrosis. Twenty-one years previously, the patient had undergone surgery and radiation therapy consisting of 60-Gy for ependymoma in the anterior horn of the right lateral ventricle. The clinical features consisting of frequent seizures of the left face and arm suddenly appeared 2 wk before admission. MRI depicted a Tl and T2-prolonged lesion in the right frontal lobe. Abnormally high uptake in this area demonstrated by MET-PET, FDG-PET, Tl-SPECT or HMPAO-SPECT suggested the presence of a recurrent tumor. A craniotomy was then performed and an intraoperative electrocorticogram showed continuous epileptic spikes in the lesion. The epileptic foci were resected and the histological features of the lesion were consistent with radiation necrosis. After surgery, the seizures disappeared and the postoperative examinations with MET-PET, FDG-PET, Tl-SPECT and HM-PAO-SPECT no longer showed abnormally high uptake. Hypermetabolism and hyperperfusion related to epileptic fits are therefore thought to result in high uptake of MET, FDG and Tl in radiation necrosis.
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PMID:Hyperperfusion and hypermetabolism in brain radiation necrosis with epileptic activity. 896 92

We describe a patient whose primary tumor was a testicular teratocarcinoma predominantly composed of embryonal carcinoma. Before chemotherapy, the retroperitoneal metastases demonstrated heterogeneous, increased glucose metabolism as measured by 2-[18F]fluoro-2-deoxy-D-glucose and PET (FDG-PET). After chemotherapy, FDG uptake was reduced to normal values despite increased tumor volume. Histology revealed a pure mature teratoma. This observation suggests that further studies are needed to determine whether tumor differentiation of testicular teratocarcinoma metastases can be assessed by measuring glucose metabolism.
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PMID:FDG-PET evaluation of retroperitoneal metastases of testicular cancer before and after chemotherapy. 899 60

Hypoxic accumulation of 2-[5,6-3H]fluoro-2-deoxy-D-glucose ([3H]FDG),L-[methyl-3H] methionine ([3H]MET), and L-[1-3H]leucine ([3H]LEU) was evaluated in two cell lines (UT-SCC-5 and UT-SCC-20) obtained from patients with squamous-cell carcinoma of the head and neck. Both cell lines were exposed to decreasing oxygen atmosphere (20%, 1.5%, or 0% O2) for 6 h, after which they were incubated for a further 1 h with tritiated FDG, MET, or LEU. An anoxic atmosphere resulted in a mean increase of [3H]FDG uptake of 120% and 46% over a baseline 20% oxygen atmosphere for UT-SCC-5 and UT-SCC-20A, respectively. Both total and acid-precipitable [3H]MET uptake remained unchanged at 0% versus baseline, whereas acid-precipitable [3H]LEU uptake decreased by 46% for UT-SCC-5 and by 34% for UT-SCC-20A at 0% O2. Our findings demonstrate that [3H]FDG accumulation is increased in hypoxic UT-SCC cell lines probably through activation of the metabolic steps associated with the glycolytic pathway. The decrease in acid-precipitable [3H]LEU uptake in hypoxia may indicate a decline in protein synthesis, whereas the unchanged [3H]MET uptake probably reflects the unaffected amino acid transport and slow incorporation of radiolabeled methyl group of MET in tumor proteins and nucleic acids. FDG and LEU, but probably not MET, warrant additional study as hypoxia-avid or hypoxia-reduced tracers for assessment of treatment effects designed to modify hypoxia.
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PMID:Influence of hypoxia on tracer accumulation in squamous-cell carcinoma: in vitro evaluation for PET imaging. 900 82

Tc-99m MIBI imaging has been used to evaluate patients with different neoplastic disorders, but its role in nuclear oncology has not been definitely established. In this study, we compared the results of Tc-99m MIBI (planar and SPECT imaging) with those of F-18 FDG PET radionuclide studies in 19 patients who had proven lung cancer. One patient was studied in follow-up. All patients underwent chest CT scans. MIBI and FDG images were qualitatively and quantitatively analyzed using region of interest analysis. Quantitative evaluation of MIBI and FDG activities in lung-tumor lesions was performed calculating tumor/nontumor ratios. On CT, 18 lung tumors were detected, while one patient was disease free. For lung lesions, the diagnostic sensitivity of planar MIBI imaging was 83%, while those of MIBI SPECT and FDG PET were both 100%. The quantitative analysis of lung-tumor MIBI and FDG activities showed that FDG uptake was significantly (P < 0.001) higher compared with MIBI uptake (5.5 +/- 3.1 vs 2.1 +/- 0.6); concordant MIBI and FDG images were found in 4 lesions in terms of central activity defect showing central necrotic tumor tissue. For lymph node abnormalities, planar MIBI scan only detected 3 lesions in 3 patients, whereas MIBI SPECT identified 9 lesions in 5 patients. FDG PET showed 13 lymph node abnormalities in 5 patients. This study shows similar results of Tc-99m MIBI SPECT and F-18 FDG PET in the diagnostic evaluation of patients with lung tumors. However, FDG lung tumor uptake was significantly higher compared with MIBI accumulation, suggesting a high glucose tumor metabolism. Thus, MIBI SPECT imaging may be useful to evaluate such patients and may be considered an alternative when PET is not available.
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PMID:Tc-99m MIBI scintigraphy in patients with lung cancer. Comparison with CT and fluorine-18 FDG PET imaging. 909 82

The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000-3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine.
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PMID:Preliminary assessment of fluorine-18 fluorodeoxyglucose positron emission tomography in patients with bladder cancer. 916 67

A well-known radiopharmaceutical 2-deoxy-2-fluoro-D-glucose widely used for positron emission tomography diagnosis in terms of glucose utilization, was re-evaluated here as a nuclear magnetic resonance pharmaceutical for cancer detection. The uptake and metabolism of FDG in the experimental tumor, MH134, transplanted to the peritoneum of C3H mice as an ascitic tumor was studied extensively by ex vivo 19F NMR. Prolonged retention of FDG and its metabolites over 2 days was confirmed in the tumor cells as well as in the heart. In these tissues, the 6-phosphate of the injected compound was converted reversibly to its epimer 2-deoxy-2-fluoro-D-mannose and further to their NDP bound forms. The metabolites were almost cleared within a day from the other healthy organs where the formation of NDP-2-deoxy-2-fluoro-D-mannose was low. Thus, the 19F NMR signal of NDP-FDM detected 1 day after the FDG injection could be used as a target signal for tumor detection. Through the use of in vivo 19F NMR spectra and 19F chemical shift images, the feasibility of this proposal was demonstrated. It was concluded that FDG-NMR has a potential for tumor diagnosis in animals.
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PMID:19F NMR of 2-deoxy-2-fluoro-D-glucose for tumor diagnosis in mice. An NDP-bound hexose analog as a new NMR target for imaging. 925 Nov 14

Experience of scintigraphic detection of bone lesion and active bone marrow involvement of multiple myeloma, especially with sestamibi and FDG-PET scans is in evolution. We report a case of intense sestamibi uptake in bone marrow correlating with the extent of the disease, while FDG-PET scans showed activity only in areas of active disease progression associated with pain. Technetium-99m-sestamibi appears to indicate the extent of the disease, while [18F]FDG-PET scans show sites of active tumor proliferation and may be useful in directing local therapy such as radiation.
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PMID:Technetium-99m-MIBI versus fluorine-18-FDG in diffuse multiple myeloma. 925 51

We report the results of FDG PET whole body scan in 75 cancer patients in whom tumor extent was defined by surgical, histological or cytological findings and clinical follow-up. Twenty-five had malignant lymphomas, 24 lung carcinomas, and 26 other types of solid tumors. Twenty-three patients were evaluated at disease onset, before therapy, and 37 at the moment of tumor recurrence; the remaining 15 patients were in complete remission after treatment and were taken as controls. Visual and quantitative PET results were compared with conventional imaging (US, CT scan and/or MRI, and Tc99m MDP bone scan). In the 60 patients with active disease, PET as well as conventional imaging were able to locate the primary tumor in all 23 patients studied at disease onset. However, with regard to lymph node and distant metastases, PET provided the same information as conventional imaging in 31 cases (51.6%), but revealed further neoplastic foci in 29 cases (48.4%), 21 in lymph nodes and 8 at distant sites. The sensitivity of PET, in comparison with conventional imaging, was 100% versus 100% for the detection of the primary tumor, 97.6% versus 55.8% for the localization of node metastases, and 100% versus 55.5% for the visualization of distant metastases. The specificity, calculated in the group of 15 disease-free patients, was 100% for PET and 86.6% for conventional imaging. The therapeutic approach was modified in 12 patients (20%) on the basis of the PET results. Furthermore, in 14 cases (23.3%) with advanced disease, PET provided complete information on tumor spread, otherwise obtainable only by taking together the results of all other diagnostic procedures. Our data indicate a higher accuracy of FDG PET whole body scan compared to conventional imaging techniques in the evaluation of metastatic spread both at initial diagnosis and during follow-up, with an important impact on therapeutic decision-making. Moreover, by providing complete information on tumor spread in some cases, PET can become a profitable tool in terms of cost reduction.
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PMID:The role of fluorine-18-deoxyglucose (FDG) positron emission tomography (PET) whole body scan (WBS) in the staging and follow-up of cancer patients: our first experience. 926 88


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