Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We developed a technique to assess the feasibility of intraoperative radionuclear detection of pheochromocytomas and their metastases. Thirteen patients were entered into the study: five control subjects with nonchromaffin adrenal tumors, eight with pheochromocytomas, and one of these patients showing bone metastasis. Each subject received thyroid blockade and an intravenous injection of 500 microCi (37 megabecquerels) 125I-labeled metaiodobenzylguanidine (MIBG) 3 days before surgery. In the five control subjects, adrenal tumor uptake never exceeded the liver or spleen uptake. One patient with a negative preoperative MIBG scan demonstrated no intraoperative uptake. Five patients with pheochromocytoma had positive preoperative scans and in one other patient preoperative scanning was not done. In each of these six patients intraoperative count ratio of pheochromocytoma/liver from 14:2 to 250:16 and pheochromocytoma/contralateral adrenal ratio from 60:1.5 to 60:16 was demonstrated. An intraoperative scan in one of these patients detected two small metastatic tumor deposits previously overlooked by the surgeon after removing a larger mass that had been localized by a preoperative 131I-MIBG scan. A negative preoperative scan in one patient was followed by an intraoperative scan demonstrating a bone metastasis with a ratio of metastasis/normal bone of 10:0.5. Specimen studies demonstrated a significant MIBG uptake ratio of tumor/plasma ranging from 95 to 667 (average 404 +/- 242) greater than in control subjects (average 25 +/- 41); in the patient with metastasis the uptake ratio of metastasis/normal bone reached 98.4. We conclude that intraoperative 125I-MIBG scanning might detect pheochromocytoma deposits overlooked by preoperative 131I-MIBG scans.
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PMID:Intraoperative radionuclear 125I-labeled metaiodobenzylguanidine scanning of pheochromocytomas and metastases. 159 59

The absence or presence of S100-positive sustentacular cells has been previously shown to be correlated with benign and malignant pheochromocytomas and paragangliomas. We evaluated a total of 17 malignant and recurrent or locally aggressive adrenal pheochromocytomas for their quantity of sustentacular cells. An absence of sustentacular cells was demonstrated in the majority of malignant cases, while the locally aggressive or recurrent group usually contained an abundance of these cells. However, in one malignant case a constant moderate number of sustentacular cells in the primary site and in two sequential metastases was found. We conclude that the absence of sustentacular cells in pheochromocytomas may indicate a lesion with a greater potential for metastasis and that sustentacular cells, when they are present in a malignant pheochromocytoma, are an integral part of the tumor.
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PMID:S100 protein-positive sustentacular cells in malignant and locally aggressive adrenal pheochromocytomas. 167 96

A patient presented with recurrent pheochromocytoma 10 years following the apparently successful surgical cure of a right adrenal pheochromocytoma. Conventional medical imaging techniques, (chest radiograph, abdominal ultrasound, and abdominal CT) suggested local recurrence for which surgery was planned. I-131 MIBG scintigraphy revealed disseminated metastatic disease that rendered attempts at surgical cure futile. The patient was treated with three therapeutic doses of I-131 MIBG with good symptomatic palliation and improvement of some biochemical parameters.
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PMID:Late presentation of metastatic pheochromocytoma: a problem case solved by I-131 MIBG scintigraphy. 169 98

Extra-adrenal pheochromocytomas may arise in any portion of the paraganglion system, although they most commonly occur below the diaphragm. The most common site of occurrence of extra-adrenal pheochromocytoma is the superior para-aortic region between the diaphragm and lower renal poles. Although the traditional teaching has been that 10% of all pheochromocytomas are at extra-adrenal sites, this may be an underestimation. Extra-adrenal pheochromocytomas probably represent at least 15% of adult and 30% of childhood pheochromocytomas. They may be malignant in up to 40% of the cases, although conflicting data add to the uncertainty of this point. Patients with tumors arising at extra-adrenal sites commonly present with headache, palpitations, sweating and hypertension. The diagnosis is most often confirmed by demonstrating increased catecholamine production, usually by measurement of urinary catecholamines and/or their metabolites. CT scanning is presently the imaging procedure of choice for localization. The roles of MRI and 131I-MIBG scintigraphy in the localization process are still being determined. Thorough preoperative pharmacological preparation, attentive intraoperative monitoring and aggressive surgical therapy all have an important role in achieving the safest and most successful outcome. Complete surgical excision is the treatment of choice for primary extra-adrenal pheochromocytoma as well as recurrent or metastatic disease. When residual tumor cannot be resected, medical therapy for symptomatic relief is preferred, since radiotherapy and chemotherapy have limited effectiveness. Extra-adrenal pheochromocytomas are more likely to recur and to metastasize than their adrenal counterparts, making lifelong followup with annual determinations of catecholamine production essential.
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PMID:Extra-adrenal pheochromocytoma. 172 90

Tumors of the peripheral nervous system include neuroblastomas, pheochromocytomas, and neuroepitheliomas. Neuroblastomas and pheochromocytomas are adrenergic in origin and share certain genetic features, whereas neuroepitheliomas are thought to be cholinergic and are characterized by distinct genetic features. Neuroblastomas are characterized by deletion of the short arm of chromosome 1 (1p), amplification of the MYCN proto-oncogene, and hyperdiploidy in subsets of tumors. All three of these genetic features have prognostic value in subsets of patients. Allelic loss of 14q also occurs with increased frequency, but the prognostic importance of this abnormality is not known yet. Pheochromocytomas have not been studied as extensively, but allelic loss for 1p appears to be a frequent change, and no clear examples of oncogene activation have been identified to date. Neuroepitheliomas are characterized by translocation between chromosomes 11 and 22. Although they have a characteristic pattern of proto-oncogene expression, it is not clear that any of these oncogenes are activated specifically, and no sites of allelic loss have been identified to date. Thus, cytogenetic and molecular analysis of neuroblastomas, pheochromocytomas, and neuroepitheliomas are useful in distinguishing them from each other and from other tumors in selected cases. Furthermore, certain genetic markers are useful in predicting clinical behavior, especially for neuroblastoma.
Cancer Metastasis Rev 1991 Dec
PMID:Biology of tumors of the peripheral nervous system. 178 33

The poor results of traditional therapy (for purposes of recovery or palliation) in malignant pheochromocytoma and the well proven uptake of [131I]metaiodobenzylguanidine (131I-MIBG) shown by these tumors, induced us to evaluate the clinical usefulness of radiometabolic therapy with 131I-MIBG. Four patients with malignant pheochromocytoma were subjected to 131I-MIBG therapy, between 1987 and 1991, in our department. They all were in an advanced stage of the disease and showed severe symptoms and poor reaction to traditional therapy. The cumulative activity given was 7.4-22.2 GBq. All patients demonstrated transient subjective improvement; in addition, both biochemical and haemodynamic parameters ameliorated. Two patients showed a reduction in the size and number of metastases seen on scintigraphy. One patient died due to progression of the disease. Three patients are still alive and in good condition. No remarkable early or late side-effects were reported. We suggest that 131I-MIBG radiometabolic therapy in advanced-stage malignant pheochromocytoma could be useful in reducing symptoms. Further investigation might show whether a greater reduction in the size of the tumor could be achieved using different therapeutic schedules or by treating the disease in its earlier stages.
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PMID:Preliminary results of [131]metaiodobenzylguanidine treatment in metastatic malignant pheochromocytoma. 182 41

Three patients with malignant pheochromocytoma were treated with [131I]metaiodobenzylguanidine (131I-MIBG). In two patients with widespread metastatic disease, the effect of treatment was palliative and of short duration. In the third case, with only residual tumor and no metastases, the treatment was effective after 22 GBq of 131I-MIBG.
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PMID:Results of [131I]metaiodobenzylguanidine therapy administered to three patients with malignant pheochromocytoma. 182 42

Malignant pheochromocytoma may present as a widespread metastatic disease, which is little or non-responsive to external beam radiotherapy and chemotherapy. The prognosis of these patients is bad due to both the progressive metastasis and the secretion of excess catecholamines which may cause hypertensive episodes. For these conditions [131I]metaiodobenzylguanidine (131I-MIBG) therapy may be an alternative treatment modality to induce both tumor remission and reduction of hormonal activity of the disease. The experience with 131I-MIBG therapy in four patients with metastatic malignant pheochromocytoma at The Netherlands Cancer Institute is reviewed. One patient with abdominal tumor recurrence and metastases to the lymph nodes and lungs had a partial remission of disease for 3 years; a second had a mixed response together with palliation and two other patients had stable disease, but were relieved of bone pain and severe hypertension, respectively. It is essential to be aware of the medication the patient is using, as many drugs are known or may be expected to interfere with the uptake and/or retention of 131I-MIBG by the tumor cells. The case of a significant reduction of 131I-MIBG uptake and retention by Labetalol in one of the patients is discussed. It is concluded that 131I-MIBG therapy may induce objective remission in patients with malignant pheochromocytoma and is certainly meaningful in the reduction of hormonal activity, the control of hypertension and the relief of pain from metastases.
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PMID:[131I]metaiodobenzylguanidine therapy of malignant pheochromocytoma: interference of medication. 182 43

Five cases of malignant pheochromocytoma (3 men and 2 women, aged 26-43 years) were treated with [131I]metaiodobenzylguanidine (131I-MIBG). One patient had a voluminous adrenal tumor and multiple distant metastases; two patients had a recurrent tumor; two others a post-surgical residual tumor. The therapeutic procedure essentially consisted of single doses (2.6-7.4 GBq) of 131I-MIBG administered by slow i.v. infusion, given in several therapeutic courses at 1-5 month intervals. The treatment resulted in a complete response in one case with residual tumor and in a partial response in the case with disseminated disease. Two cases showed stabilization of the disease, whereas therapy was ineffective in the fifth case. Nevertheless, pain relief was observed in this patient. The treatment had a very low toxicity and was well tolerated by all patients.
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PMID:[131I]metaiodobenzylguanidine treatment of malignant pheochromocytoma: experience of the Rome group. 182 40

Our experience with [131I]metaiodobenzylguanidine (131I-MIBG) therapy in a 10 year old boy is reported. At disease onset, in May 1988, this boy presented a large mass in the upper left abdominal quadrant, which was resected with a histopathological diagnosis of extra-adrenal malignant pheochromocytoma (paraganglioma). He subsequently underwent two further surgical resections and chemotherapy. When 131I-MIBG therapy was started, in June 1990, skeletal and abdominal metastases were present. These localizations were revealed by 131I-MIBG scans and confirmed by x-ray examination. At present 6 courses of therapy have been performed with a cumulative activity of 29.6 GBq. Side-effects have been limited to vomiting and mild thrombocytopenia, lasting 2 weeks during the second course of therapy. After 15 months of therapy, a progressive reduction of MIBG uptake, coupled with a stabilization of the lythic lesions, has been observed.
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PMID:[131I]metaiodobenzylguanidine therapy in paraganglioma. 182 45


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