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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The potential of seven tracers for the metabolic imaging of tumors by positron emission tomography was studied using five experimental tumor models. The tracers examined were 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG), 2-deoxy-2-[18F]fluoro-D-galactose (2-[18F]FdGal) and 2-deoxy-2-[18F]fluoro-L-fucose (2-[18F]FdFuc) for investigating energy metabolism. L-[methyl-11C]Methionine ([11C]Met) and 6-[18F]fluoro-L-fucose (6-[18F]FFuc) were used for assessing protein and glycoprotein synthesis, while [3H]thymidine ([3H]Thd) and 2-deoxy-5'-[18F]fluorouridine ([18F]FdUrd) were used to investigate nucleic acid metabolism. The highest mean uptake by the five different tumors was found for [3H]Thd, followed in order by [18F]FDG, [11C]Met, 2-[18F]FdGal, [18F]FdUrd, 2-[18F]FdFuc and 6-[18F]FFuc. The tumor-to-tissue uptake ratios indicated that the nucleosides, [11C]Met and 6-[18F]FFuc were better tracers in the brain region. All the tracers except for the fucose analogs were suitable for the thoracic region, while [11C]Thd and [18F]FDG were superior in the abdominal region. In comparison with the primary tumor model of Lewis lung carcinoma (3LL), [3H]Thd uptake in the artificial metastatic 3LL model showed the maximum enhancement, followed by [18F]FDG, [11C]Met and the other tracers. The [18F]FDG uptake correlated with the [3H]Thd uptake. [18F]FdUrd, 6-[18F]FFuc and 2-[18F]FdGal could be used for distinguishing different types of tumors. The combined use of these radiotracers can possibly allow the assessment of tumor metabolism, and this indicates the viability of tumors.
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PMID:Tumor diagnosis by PET: potential of seven tracers examined in five experimental tumors including an artificial metastasis model. 138 72

In a prospective study 16 patients with cervical lymph node metastases from an occult tumor were analyzed by (18F)FDG positron emission tomography (PET). The aim of this study was to locate the primary tumor. In 7 patients a localized increase in activity was seen on PET, with this site of activity histologically proven in 4 patients. No biopsies were taken in 3 patients in areas with a high risk of complications. In a follow-up procedure at 2-22 months after primary radiation therapy in the other 9 patients, no primary tumor has been identified to date.
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PMID:[Positron emission tomography for primary tumor detection in lymph node metastases with unknown primary tumor]. 870 30

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 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

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

We describe the case of a 42-year old female patient with a carcinoma of the adrenal cortex. The primary tumor was resected without residual tumor tissue; only two weeks later there was a new large tumor formation in the adrenal gland's bed. PET-investigation showed the large local recurrency, multiple lung-, and liver-metastasis, so that no further operative therapy was performed. FDG-PET seems to be suitable for diagnosis and staging of adrenal cortex carcinoma in one single examination.
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PMID:[Imaging of an adrenal cortex carcinoma and its metastasis with FDG-PET]. 1039 78

18F-fluorodeoxyglucose positron emission tomography was able to identify previously unknown primary tumors in 2 of 4 patients after an unsuccessful conventional diagnostic workup such as chest radiography, ultrasound, computed tomography, MRI and various endoscopies. The 2 patients in which the primary tumors were detected proved to have a carcinoma of the lung, one of the patients received radiotherapy and chemotherapy after the detection of the primary tumor by FDG PET. The primary tumor of the lung demonstrated no focal FDG uptake after the successive treatment. On the other hand, in one patient with prostatic carcinoma and another in which the primary tumor has yet to be detected, FDG PET was unable to identify the primary tumor. This suggests a limitation of PET studies in detecting cancers. Because of increased glycolysis in cancer cells, FDG PET can be used to detect cancers with its high sensitivity, surveying the entire body non-invasively in one session. PET has the advantage of detecting primary tumors of an unknown origin when compared to conventional diagnostic studies.
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PMID:[Evaluation of 18F-FDG positron emission tomography (PET) in the detection of unknown primary tumors]. 1042 68

False positive findings in primary tumor and metastasis diagnostics by FDG-PET due to FDG-uptake in inflammatory foci are documented in literature. The demonstrated case reveals that increased uptake of FDG in activated neutrophile granulocytes and macrophages has to be taken into consideration in therapy control under chemotherapy, too. In a 53 year old patient FDG-PET was performed after chemotherapy of an abdominal Non-Hodgkin lymphoma for evaluation of persistent tumor vitality. The margin of the persisting mass showed increased uptake of glucose. Histology documented a necrotic center surrounded by granulation tissue.
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PMID:[Granulation tissue: pitfall in therapy control with F-18-FDG PET after chemotherapy]. 1061 68

Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. We applied high-activity Sm-153-EDTMP therapy within a multimodal therapy concept to improve local control of an unresectable osteosarcoma with poor response to initial polychemotherapy. A 21-year-old woman with an extended, unresectable pelvic osteosarcoma and multiple pulmonary metastases was treated with high-activity of Sm-153- EDTMP (150 MBq/kg BW, total 8.1 GBq). Afterwards external radiotherapy of the primary tumor site was performed and polychemotherapy was continued, followed by autologous peripheral blood stem cell reinfusion. Within 48 h after Sm-153-EDTMP application the patient had complete pain relief. After three weeks the response was documented by 3-phase Tc-99m-MDP bone scintigraphy (primary tumor and metastases: decreased tracer uptake), whole-body F-18-FDG-PET (primary tumor and metastases: diminution of glucose metabolism) and thoracic CT (metastases: reduction of size). The present case warrants further evaluation of feasibility and efficacy of this multimodal therapy combination of high-activity Sm-153-EDTMP therapy, external radiation, polychemotherapy and stem cell support for unresectable osteosarcomas.
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PMID:High-activity samarium-153-EDTMP therapy in unresectable osteosarcoma. 1061 69

Purpose: To compare [18F]2-deoxy-2-fluoro-D-glucose-positron emission tomography (FDG-PET) and computed tomography (CT) scans in assessment of response to neoadjuvant chemotherapy in advanced head and neck cancer.Materials and Methods: In a prospective clinical study, advanced head and neck cancer patients were enrolled in a neoadjuvant organ preservation protocol and received CT and FDG-PET scans prior to and after 2 or 3 rounds of chemotherapy. All patients had prechemotherapy and postchemotherapy tissue biopsies within the tumor region. Patients were then classified as pathologic complete response (PCR) or residual disease (RD) based on biopsies. Analysis of the tumor activity, using FDG-PET, was performed using standardized uptake ratios (SUR) in the region of the primary tumor. Analysis of the tumor size, using contrast enhanced CT, was performed using measurements of the primary tumor in 3 dimensions.Results: Nineteen of the 28 patients with stage III and IV cancer of the head and neck enrolled between December 1994 and May 1996 completed the study. Three patients were PCR and had a mean SUR reduction of 82% by positron emission tomography (PET) and volume reduction of 80% by CT. Sixteen patients had RD after chemotherapy, their SUR and volume reductions were 32% and 41%, respectively. Reduction in SUR with PET was significant. The mean tumor volume reduction by CT approached statistical significance. There was a positive correlation between the percent reduction in tumor volume and SUR (P < 0.004).Conclusion: FDG-PET and CT imaging are at least equivalent in correctly assessing tumor response to chemotherapy with a trend toward better performance by PET.
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PMID:FDG-PET and CT in Evaluation of Chemotherapy in Advanced Head and Neck Cancer. 1074 76


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