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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A total of 48 patients with squamous cell carcinomas (SCC) of the head and neck were examined with positron emission tomography (PET) and 18Fluor-deoxyglucose (FDG). In 25 cases the FDG-PET-data were compared with flow cytometric data of the lesions to investigate the value of PET for the noninvasive determination of a tumor's proliferative activity. The quantitative analysis of the radioactivity concentrations revealed two groups of tumors with a different FDG-uptake. A correlation was seen between the proliferative index and the FDG-uptake with an r-value of 0.64 in the lower uptake group and an r-value of 0.81 in the higher uptake group. There was no correlation between any clinicopathological or morphological parameters of the tumors and the FDG-uptake. It is suggested that the different FDG uptake may correspond to differences at the molecular level. The PET-evaluation of therapeutic effects in patients with advanced SCC of the head and neck revealed different posttherapeutic changes of the metabolism in tumors and in lymph node metastases. Tumors were more sensitive to therapy than lymph node metastases. There was a high correlation between the growth rate and the change in FDG uptake with a different regression function for tumors and for lymph nodes. The data demonstrate the usefulness of PET and FDG for the evaluation of early therapeutic effects. Therefore PET can be applied for the treatment planning in patients with malignant tumors of the head and neck.
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PMID:The relevance of positron emission tomography for the diagnosis and treatment of head and neck tumors. 823 Mar 73

The distribution of specific radiolabeled biological compounds in tumor tissues can be imaged by positron emission tomography (PET). The substance used is fluorodeoxyglucose, labeled with the positron emitter fluorine-18. This substance is partly trapped in tumor cells with increased glucose metabolism. This noninvasive imaging technique allows to assess quantitatively and in three dimensions the extent of metastatic disease in ENT cancer. The case presented illustrates the important value we foresee for this new imaging modality in the presurgical staging of cervical metastatic disease of ENT tumors. Sensitivity and specificity of the PET-FDG imaging technique for the loco-regional staging of ENT cancer are, according to preliminary results of an ongoing, prospective clinical study, very high.
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PMID:[Positron emission tomography (PET) in the preoperative evaluation of cervical lymph node metastasis of ORL cancer]. 829 Aug 39

Positron emission tomography is an imaging technique that produces images reflective of tissue biochemistry rather than anatomy. Utilizing different isotopes, many biochemical processes can be studied repetitively and non-invasively in cancers in vivo. Malignant tissue is characterized by an accelerated rate of glycolysis. This biochemical characteristic of malignancy can be exploited by PET imaging with the radiopharmaceutical FDG. PET with FDG has been successful in imaging primary and metastatic cancer of the breast, colon, lung, head and neck, as well as sarcomas and lymphomas. PET FDG imaging has potential as a screening, diagnostic and staging tool in cancer. Recently, whole body PET techniques have been developed which permit imaging of the entire body during a single scanning session. PET also has tremendous potential as a cancer research tool to study serial estimates of tumor glycolysis, DNA turnover, oxygen metabolism, protein synthesis, and blood.
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PMID:Use of positron emission tomography in oncology. 834 60

To determine the usefulness of positron emission tomography with fluoro-2-deoxyglucose (PET-FDG) in assessing mediastinal disease in patients with non-small-cell lung cancer (NSCLC) and to compare its yield to that of computed tomography (CT), we performed a prospective consecutive sample investigation in a university hospital and its related clinics. In 30 patients with NSCLC with clinical stage I (T1-2, NO, MO) disease, we compared the results of chest CT and PET-FDG with the findings at surgical exploration of the mediastinum. Seven (77%) of nine patients with surgically proven mediastinal metastasis were identified by the PET-FDG results, with four false-positives in 21 patients with negative lymph node dissections (p = 0.004). Using the results of pathologic examination of mediastinal lymph nodes as the criterion standard, the diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) for PET-FDG imaging of mediastinal metastases were 78%, 81%, 80%, 64%, and 89%, respectively. The sensitivity, specificity, accuracy, PPV, and NPV for chest CT in the detection of mediastinal metastasis were 56%, 86%, 77%, 63%, and 87%, respectively. CT and PET-FDG results agreed in 21 patients. The diagnostic accuracy of the combined imaging modalities was 90%. We concluded that mediastinal uptake of FDG correlates with the extent of mediastinal involvement of NSCLC and may contribute to preoperative staging. PET-FDG imaging complements chest CT in the noninvasive evaluation of NSCLC, and strategies for its use merit further investigation.
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PMID:Mediastinal staging of non-small-cell lung cancer with positron emission tomography. 852 Jul 80

We evaluated the usefulness of fluorine-18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG PET) in the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer and then compared the findings with the results of X-ray CT by region based on the histological diagnoses. We examined 29 patients with non-small cell lung cancer. One hundred and thirty-two mediastinal lymph nodes were surgically removed and the histological diagnoses were confirmed. FDG PET images, including 146 mediastinal regions, were visually analysed and the mediastinal lymph nodes were scored as positive when the FDG uptake was higher than that in the other mediastinal structures. On the X-ray CT scans, any mediastinal lymph nodes with a diameter of 10 mm or larger were scored as positive. All three examinations were successfully performed on 71 regions. For FDG PET, we found a sensitivity of 76%, a specificity of 98% and an accuracy of 93%. On the other hand, for X-ray CT a sensitivity of 65%, a specificity of 87% and an accuracy of 82% were observed. A significant difference was observed in respect of both specificity and accuracy (P<0.05). Based on the above findings, FDG PET is suggested to be superior to X-ray CT when used for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer.
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PMID:The usefulness of FDG positron emission tomography for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer: a comparative study with X-ray computed tomography. 866 11

2-[18F]fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) is a promising imaging procedure for detecting primary and metastatic cancer in the lungs. We have, however, failed to detect some small tumors in the lower lobes of the lungs. This study aimed to determine whether increase 18F background activity in the dependent lower lungs is present, which could make lesion detection more difficult. We measured the standardized uptake values (SUVs) for FDG of normal lung remote from the nodular lesion in 16 patients with newly diagnosed untreated lung lesions strongly suspected to represent non-small cell lung cancers. In addition, 15 patients with known or suspected primary breast cancers without pulmonary lesions were included as control subjects. After PET transmission images of the thorax were obtained, approximately 370 MBq of FDG was injected intravenously and imaging was immediately begun. Patients were supine throughout the study. SUVs were determined with images obtained 50-70 min after FDG injection. Regions of interest (ROIs) of 6x6 pixels were positioned over normal lung in anterior, mid, and posterior portions of upper, middle, and lower lung fields. Thus, as many as 18 ROIs were positioned in each patient. The SUVs of the posterior portion were significantly higher than those of the anterior and mid portions in the population of 31 cases (P <0.001). Also, the mean SUV of the lower lung field was significantly higher than the SUVs of the upper and middle lung fields in this population (P <0.01). This pattern was seen among the two groups of 16 patients suspected of having lung cancer and 15 control subjects. Background 18F activity was highest in posterior and lower lung in these patients. The maximum value of mean SUV observed in normal posterior lower lung was 0.804+/-0.230 (41% greater than the mean SUV in the anterior upper lung), which is in the range of the apparent SUV for a 5-mm lung lesion, with higher SUV, due to recovery coefficient issues. Thus this phenomenon could contribute to occasional false-negative lesions in those areas. Increased blood flow and FDG delivery and also scatter from heart and liver may contribute to the increased lower lung background activity. Regional differences in normal lung FDG uptake are significant and should be considered when interpreting pulmonary PET studies in patients with suspected primary or metastatic lung cancer.
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PMID:Regional 2-[18F]fluoro-2-deoxy-D-glucose uptake varies in normal lung. 869 55

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

This prospective study based on 48 patients showed that FDG-PET has a significantly higher sensitivity for the detection of lymph node metastases compared with palpation and it appears that FDG-PET has a similar sensitivity to CT-scanning. According to our data, FDG-PET is a highly specific method in the evaluation of neck nodes. This new imaging technique allows a tridimensional study and is easy to interpret. Therefore, FDG-PET seems to be a valuable imaging technique for the detection of cervical lymph node metastasis.
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PMID:The role of FDG-PET in the preoperative assessment of N-staging in head and neck cancer. 872 43

Initial reports suggest that positron emission tomography with [18F]fluorodeoxyglucose (FDG-PET) may offer greater diagnostic accuracy and versatility than conventional radiology in staging patients with metastatic melanoma. We reviewed the first 100 melanoma patients to have PET imaging at our institution. PET findings were correlated with all other available results, including plain X-ray, computed tomography (CT), magnetic resonance (MR) imaging, bone scintigraphy, clinical findings and histopathology. A total of 415 metastatic lesions were evaluated, 388 (93%) of which were detected by PET. In 20 patients, PET detected 24 metastases up to 6 months earlier than conventional imaging or physical examination. Selection of surgical or medical management was specifically influenced by PET findings in 22 patients, and PET was used to clarify another 12 cases where CT was inconclusive. In nine patients undergoing chemotherapy, PET was used to assess response to treatment. We conclude that FDG-PET can accurately detect metastatic melanoma with a single non-invasive scan, and can demonstrate some metastases months before conventional imaging techniques. PET can improve the selection of patients for surgery, has potential for monitoring response to treatment and may prove a cost-effective means of staging melanoma patients.
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PMID:Positron emission tomography in the detection and management of metastatic melanoma. 887 53

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


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