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

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

Cells in tumors may be exposed to adverse conditions such as nutrient deprivation, acidic pH and hypoxia. It has been shown previously that exposure to hypoxia, acidosis and glucose starvation in vitro increases the experimental metastatic ability of murine KHT-LP1 sarcoma, SCC-VII squamous carcinoma and B16 melanoma cells. This effect was most marked when cells were allowed to recover under normal in vitro growth conditions before injection. In the present study we examined whether the invasive capacity of the cells could be influenced by these modifications of the cell microenvironment. We used Matrigel, a basement membrane-like preparation in a two-chamber invasion assay to address this issue. Both KHT-LP1 and SCC-VII murine cell lines showed an increased ability to invade through Matrigel after hypoxia, and glucose starvation, but there was no consistent change in invasive capacity following acidosis exposure. The results for hypoxia and glucose starvation are in agreement with our previous studies of metastatic ability for these cell lines and we confirmed this for KHT-LP1 cells exposed to hypoxia in the current study. In parallel with the invasion assays, we compared cathepsin (L + B) content of the cells in treated and control suspensions. The effect observed varied according to the cell line and the treatment received (hypoxia, glucose starvation). There was an increase of cathepsin content for KHT-LP1 cells exposed to hypoxia and this increase correlated well with the increase of the invasion ability through Matrigel. We did not observe any increase of cathepsin for hypoxia-treated SCC-VII or for KHT-LP1 and SCC-VII cells treated with glucose starvation. These results suggest that transient hypoxia and glucose starvation can increase the invasive ability of tumor cell lines and thus may cause tumor progression by facilitating the invasive step of the metastatic process. The increased levels of cathepsin (L + B) in the KHT-LP1 cells treated with hypoxia, compared to control non-treated cells, may play a part in this increased invasive capacity.
Clin Exp Metastasis 1997 Jan
PMID:Exposure to hypoxia, glucose starvation and acidosis: effect on invasive capacity of murine tumor cells and correlation with cathepsin (L + B) secretion. 900 2

A 52-year-old-woman with non-insulin-dependent diabetes mellitus developed carcinoma of the pancreas and had a Whipple's resection performed. She required pancreatic exocrine supplements and insulin post-operatively. Five years later metastatic disease became apparent, and was accompanied by episodic spontaneous hypoglycaemia necessitating the cessation of insulin therapy. Hormonal analysis was performed, off insulin, at a time of hypoglycaemia (glucose 0.9 mmol l-1) and showed negligible insulin concentrations (< 2 mU l-1) but raised IGF-II together with low IGF-I concentrations (1.85 and 0.1 U ml-1, respectively). The association between diabetes and pancreatic carcinoma, and the pathogenesis of non-islet cell tumour induced hypoglycaemia (NICTH) are discussed.
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PMID:Spontaneous hypoglycaemia in a noninsulin-dependent diabetes mellitus patient with disseminated pancreatic carcinoma. 911 88

In this study, 15 patients (4 men and 11 women, mean age: 50 +/- 13 years) with unilateral adrenal masses detected on ultrasound (US), Computed Tomography (CT) and/or Magnetic Resonance (MR) studies were submitted to positron emission tomography (PET) with fluorine-18 deoxyglucose (FDG). Histology demonstrated 3 adenomas, 1 myelolipoma, 1 angiolipoma, 1 neurinoma, 1 cyst, 1 malignant pheochromocytoma, 4 carcinomas and 3 metastases. The patient population was divided into two groups. Group 1 (n = 7) consisted of benign adrenal lesions. Group 2 consisted of malignant adrenal tumors. Lesion measurements were performed on the basis of the results of US, CT and/or MR images. In Group 1, no FDG uptake was observed in adrenal masses. Conversely, in Group 2 adrenal lesions showed abnormally increased FDG uptake, suggesting high glucose tumor metabolism. No significant difference in lesion size was observed between Groups 1 and 2 (5.6 +/- 4.0 vs 6.3 +/- 3.0 cm). Furthermore, in 6 patients of Group 2, total body PET images showed abnormal FDG uptake in extra-adrenal locations, such as chest (n = 2) and abdominal (n = 5) lymph nodes, lungs (n = 6), liver (n = 5), pancreas (n = 1), bone (n = 1) and muscle (n = 1) tissues. In conclusion, the results of this study suggest that PET imaging with FDG can characterize adrenal masses. In particular, abnormally increased FDG uptake in adrenal malignancies allows to differentiate these abnormalities from benign lesions. Furthermore, total body imaging PET can identify extra-adrenal tumor sites in patients with malignant tumors.
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PMID:[Positron emission tomography (PET) with fludeoxyglucose F 18 in the study of adrenal masses: comparison of benign and malignant lesions]. 912 72

Nuclear Medicine procedures include in vitro techniques able to detect and characterize liver metastases. Among the in vitro applications, circulating tumour markers level determination provides information about the response to therapy and the presence of active disease. While after a successful antineoplastic treatment the serum biological marker level usually falls, a progressive increase represents an alarm signal of occult/residual tumour or metastatic dissemination. However, this method is not able to identify the site of the lesion, therefore complementary imaging techniques are needed to confirm or exclude the diagnostic suspicion. The main advantages of the in vitro methods are the low cost and, consequently, the possibility of periodically checking of tumour activity. The in vivo nuclear medicine techniques are usually performed as second level test. In fact, they can play a role in detecting and characterizing hepatic metastases when radiological methods are inconclusive or when selected tumour seeking agents (i.e. radiolabelled antibodies, radioiodinated mIBG, Octreotide, etc.) can be used. Moreover, the introduction of PET procedures has provided physicians with a useful tool for the evaluation of tumour behaviour (glucose consumption, proteic, synthesis, receptor expression). A further significant diagnostic improvement is represented by the recent introduction of the multimodality co-registration of images (including CT scan, MRI, SPET, PET). The fusion imaging allows a superimposition of the functional and metabolic information to the morphological one.
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PMID:[Nuclear medicine approach for the detection and characterization of liver metastasis]. 921 67

The extracellular pH in malignant tumors is known to be lower than in normal tissues and may therefore facilitate extracellular activation of secreted lysosomal cathepsins. We have tested the capability of human mammary cells (continuous cell lines and primary culture) to acidify their extracellular environment, using two techniques. By measuring pH changes through alterations of phenolsulfone phthaleine absorbance, we found that the more aggressive MDA-MB-231 human breast cancer cells were more active in acidifying a non-buffered balanced salt solution than the estrogen receptor positive MCF7 and ZR75 cell lines and than normal mammary epithelial cells in primary culture. Metastatic breast cancer cells from pleural effusions were up to 200-fold more active in acidifying their extracellular milieu than non-malignant mammary cells cultured in the same conditions, strongly suggesting that this difference also occurs in vivo. The use of inhibitors in the presence or absence of glucose showed that both lactate and an ATP-driven proton pump sharing some characteristics of the vacuolar H+ pump were involved. Bafilomycin A1, a specific inhibitor of the vacuolar (V-type) ATP-H+ pump inhibited part of the acidification by MCF7 cells, but not by MDA-MB-231 cells. We also used microelectrodes to measure extracellular pH, in close contact to the MCF7 breast cancer cells. The pH at the free surface of MCF7 cells was lower by 0.33 +/- 0.14 unit than that of the surrounding medium, while insertion of the microelectrode tip beneath the attached surface of the cells showed a greater lowering of pH from 0.3 to 1.7 pH unit as long as cell attachment on the substrate prevented H+ diffusion. We conclude that breast carcinoma cells have a higher capacity for acidifying their extracellular milieu than normal mammary cells, and that both a plasma membrane H(+)-ATPase, and lactic acid production are involved in this acidification. It is therefore possible that the aspartyl and cysteinyl pro-cathepsins secreted in excess by tumor cells may be activated extracellularly in vivo close to the basement membrane.
Clin Exp Metastasis 1997 Jul
PMID:Breast cancer cells have a high capacity to acidify extracellular milieu by a dual mechanism. 921 26

Tumor cells exposed to a growth stress such as low pH, glucose starvation and hypoxia have been shown to exhibit a transient increase in experimental metastatic potential, particularly when allowed to recover under normal growth conditions for a period of 24-48 h. In this study we examined whether this increase in metastatic ability could be explained by changes in the expression of a number of different metastasis-associated genes, when the cells were exposed to similar conditions (24-48 h exposure to the stress condition followed by 0-48 h recovery under normal growth conditions). Although the cell lines used (KHT fibrosarcoma, SCC VII squamous cell carcinoma, and B16F1 melanoma) demonstrated altered metastatic ability after the treatment, no overall temporal correlation between changes in the mRNA levels for cathepsin B, cathepsin L, nm23, TIMP-1, osteopontin, or VEGF and metastatic ability in the three cell lines was observed. The production of gelatinase A (72 kDa collagenase) and gelatinase B (92 kDa collagenase) was also measured by gelatin zymography. There was an increase in production of these enzymes with increasing recovery time, but it did not parallel changes in metastatic potential. Although these results suggest that the products of most of the genes studied may not be involved in the transient metastatic changes, further studies are required to establish whether changes in protein levels track with changes in mRNA levels for these genes.
Clin Exp Metastasis 1997 Sep
PMID:An examination of the effects of hypoxia, acidosis, and glucose starvation on the expression of metastasis-associated genes in murine tumor cells. 924 50

Increased glucose metabolism by malignant tissue can be visualized with positron emission tomography (PET), using the radiolabeled glucose analogue F-18 fluorodeoxyglucose (FDG). Depending on the criteria of image interpretation FDG-PET allows detection of breast cancer with a sensitivity of 68% to 94% and a specificity of 84% to 97%. However, sensitivity to visualize small tumors (< 1 cm) is limited. Positron emission tomography demonstrates tumor involvement of regional lymph nodes with high accuracy, predominantly in patients with advanced breast cancer. The sensitivity for the detection of axillary lymph node metastases was 79% with a corresponding specificity of 96%. Lymph node metastases could not be identified in four of six patients with small primary breast cancer (stage pT1), resulting in a sensitivity of only 33% in these patients. By visualizing primary tumors and metastases in one imaging procedure, PET imaging may allow the effective staging of breast cancer patients. Further studies are needed to define the role of scintigraphic techniques for the diagnostic work-up in patients.
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PMID:[Possible uses of positron emission tomography in breast carcinoma]. 927 7

Scintigraphy using [111In-DTPA-d-Phe1]-pentetreotide or pentavalent technetium-99m-dimercaptosuccinic acid [99mTc(V)-DMSA] has been shown to localize well-differentiated and slowly growing neuroendocrine tumours, whereas increased fluorodeoxyglucose (FDG) uptake is associated with malignancy. The aim of this study was to compare the value of fluorine-18 FDG positron emission tomography (PET) with that of somatostatin receptor scintigraphy (SS-R) and dual-radionuclide scintigraphy [SS-R and 99mTc(V)-DMSA = DNS] in detecting malignant neuroendocrine tumours. Fifteen patients with metastasizing gastroenteropancreatic tumours (GEP tumours; n = 7), medullary thyroid carcinomas (MTCs; n = 8) and elevated tumour markers [GEP tumours: 5-hydroxyindoleacetic acid, insulin; MTCs: calcitonin, carcinoembryonic antigen (CEA)] were studied. Prior to PET, all patients with GEP tumours underwent SS-R. DNS was performed in all patients with MTC. Patients had been fasting for at least 12 h and normal glucose plasma levels were confirmed. Sixty minutes after intravenous administration of 18F-FDG (mean: 374 MBq) whole-body PET and regional scans were performed. In addition, the resected tissues were prepared for immunocytochemistry examination (cell cycle-associated Ki-67 antigen). In two patients with less-differentiated GEP tumours associated with high proliferative activity and increased FDG uptake, SS-R failed to detect any lesion. In comparison, in four patients with well-differentiated GEP tumours showing low proliferative activity, SS-R localized four primary tumours, 22 lymph node metastases and 18 malignant liver lesions, whereas 18F-FDG PET demonstrated normal distribution. In one patient with a metastasizing carcinoid (medium proliferative activity) SS-R localized multiple metastases, whereas PET demonstrated low FDG uptake in all known metastases. In patients with recurrent MTC and rapidly increasing CEA levels DNS detected only three lesions in two patients, whereas PET demonstrated one pulmonary, three osseous, 20 mediastinal, ten locoregional, and four liver metastases in seven patients. Twenty-nine malignant lesions were confirmed by follow-up and nine lymph node metastases could be surgically removed. In conclusion, PET imaging of gastroenteropancreatic tumours revealed increased glucose metabolism only in less-differentiated GEP tumours with high proliferative activity and metastasizing MTC associated with rapidly increasing CEA levels. Therefore, additional 18F-FDG PET should be performed only if SS-R or DNS is negative.
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PMID:Limited value of fluorine-18 fluorodeoxyglucose positron emission tomography for the imaging of neuroendocrine tumours. 939 78

Based on the increased glucose metabolism of malignant tissue, positron emission tomography (PET), using the radiolabeled glucose analog 18F-fluorodeoxyglucose (FDG), allows identification of breast cancer. Based on the criteria implemented in image interpretation, sensitivity of PET imaging ranged from 68% to 94% with a specificity between 84% and 97%. However, sensitivity for small tumors (< 1 cm) was found to be low. PET demonstrates tumor involvement of regional lymph nodes with high accuracy, predominantly in patients with advanced breast cancer. The sensitivity for the detection of axillary lymph node metastases was 79%, increasing to 94% in patients with primary breast tumors larger than 2 cm in diameter. Corresponding specificities were 96 and 100%, respectively. Lymph node metastases could not be identified in four of six patients with small primary breast cancers (stage pT1), resulting in a sensitivity of only 33% in these patients. By visualizing primary tumors and metastases in one imaging procedure, PET imaging may allow the effective staging of breast cancer patients. Response to treatment may be assessed at an earlier point than with imaging techniques currently used. Therefore, indications for PET studies in the future may be the evaluation of loco-regional lymph nodes, whole-body staging, diagnosis of local recurrence and therapy monitoring.
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PMID:[Diagnosis of breast carcinoma and locoregional lymph nodes with positron emission tomography]. 942 20


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