Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031511 (pheochromocytoma)
 14,622 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 7-year-old female was discovered to be severely hypertensive. Urinary noradrenaline excretion and plasma noradrenaline level were elevated. Plasma renin activity was markedly elevated. She was found to have a mass in the hilus of the left kidney and left renal artery stenosis. Magnetic resonance imaging (MRI) of the mass revealed an extremely bright lesion on T2 weighted image. DMSA renal scintigraphy revealed a low uptake rate (4.7%) in the left kidney. A diagnosis of extra-adrenal pheochromocytoma associated with left sided renal artery stenosis was made. The mass and left kidney were removed. Electronmicroscopic examination of the mass revealed characteristic neurosecretory granules. There was only slight fibrosis in the wall of the removed left renal artery.
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PMID:[A case of a child with extra-adrenal pheochromocytoma associated with renovascular hypertension]. 141 54

A case of false positive I-131 MIBG imaging for detection of pheochromocytoma is presented. There was an area of increased tracer uptake in the left renal region that showed steadily reducing activity over a period of three days. This raised the suspicion of a dilated renal pelvis, which was later confirmed by Tc-99m DTPA imaging. It is advisable in cases of ambiguous I-131 MIBG imaging to use Tc-99m DTPA rather than Tc-99m DMSA for localizing the kidneys and renal pelvis.
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PMID:A false positive I-131 MIBG due to dilated renal pelvis: a case report. 285 6

In-111 pentetreotide scintigraphy of 10 patients with residual or metastatic medullary thyroid carcinoma is described. Six patients had sporadic tumor and 4 had MEN IIB. Foci of increased tracer uptake were observed in 9 patients: in the thyroid bed (4 patients), the mediastinum (3 patients.), the shoulder area and left lower abdomen (1 patient), and the left upper abdomen (1 patient). The 10th patient had no abnormal uptake. CT confirmed 2 mediastinal lesions and 2 out of 3 thyroid masses, but did not detect the thyroid remnants or the lesions in the shoulder area and abdomen. Lung lesions < or = 1 cm in diameter and ill-defined liver foci (2 patients) were seen on CT, but not on scintigraphy. Small liver metastases not demonstrated on CT or on scintigraphy were identified at surgery in a MEN IIB patient. Elevated urinary epinephrine was found in 2 out of 4 MEN IIB patients. In one, tracer uptake in the left adrenal corresponded to a mass on CT, to pathological uptake of MIBG and DMSA, and to a tumor removed at surgery. The second patient had peritoneal spread of malignant pheochromocytoma (at surgery), but negative CT and only a single focus in the left lower abdomen on scintigraphy. Somatostatin-receptor imaging is useful for the detection of residual and recurrent medullary thyroid carcinoma, and may identify pheochromocytoma in MEN IIB patients.
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PMID:Somatostatin-receptor imaging of medullary thyroid carcinoma. 791 71

Three radiolabelled substances, 111In-pentetreotide, 99mTc-(V)DMSA and 123I-MIBG with different kinetics but similar tumor seeking behavior, were i.v. injected to assess and correlate their clinical value in metastatic malignant pheochromocytomas (4 patients), stage III and IV neuroblastomas (7 patients) and medullary thyroid carcinomas (6 patients). All II pheochromocytoma/neuroblastoma patients received i.v. a dose of III MBq (3 mCi) of 123I-MIBG and 185 MBq (5 mCi) of 111In-pentetreotide, within approximately weeks each other. Furthermore, in 4 of these patients as well as in all medullary thyroid carcinoma patients 111 MBq (3 mCi) of 99mTc-(V)DMSA were applied i.v. I week prior to the pentetreotide/mlBG scans. Four patients (malignant pheochromocytoma) with a total of 7 foci showing MIBG accumulation had 3 sites with pentetreotide and 1 site with (V)DMSA uptake, while in 7 patients (neuroblastora) with 15 foci showing MIBG accumulation 10 sites had detectable pentetreotide and 3 sites detectable (V)DMSA. Of the three radiotracers, 111In-pentetreotide used for somatostatin receptor identification holds promise mainly in cases where foci imaged with 123I-MIBG are negative. 111In-pentetreotide is unlikely to replace 123I-MIBG as a first-line routine diagnostic scintigraphic modality; compared to pentetreotide or MIBG, (V)DMSA seems to be highly sensitive only in medullary thyroid carcinomas.
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PMID:Comparison of In-111 pentetreotide, Tc-99m (V)DMSA and I-123 mlBG scintimaging in neural crest tumors. 917 99

Previous studies of the intraoperative use of a hand-held gamma probe to localize metastases and primary tumors of colorectal cancer have shown improved assessment of tumor spread and changes in surgical management based on added information gained by radioimmunoguided surgery. Following the injection of 180 MBq [111In-DTPA-D-Phe1]-pentetreotide and/or 500 MBq 99mTc-dimercaptosuccinic acid (both for dual-radionuclide scintigraphy) preoperative somatostatin receptor imaging [11 patients with GEP tumors] and dual-radionuclide scintigraphy. (8 patients with relapsing medullary thyroid carcinomas) was performed. One patient with a metastasizing pheochromocytoma underwent 123]-MIBg scintigraphy. Results were combined with the information obtained from conventional imaging modalities. Intraoperative radiodetection was performed 24 hours after administration of [111In-DTPA-D-Phe1]-pentetreotide or 4 hours following the injection of 99mTc(V)DMSA using a hand-held gamma probe (Tec Probe 2000. Stratec, FRG). Intraoperative gamma counting localized 39 somatostatin receptor positive lesions of GEP tumors whereas preoperative receptor imaging visualized 81%, surgical palpation 41% and radiological imaging modalities localized only 31%. In 8 patients with recurrent medullary thyroid carcinoma the surgeon was successful in localizing and removing 18 tumor lesions by the help of the gamma probe. Dual-radionuclide scintigraphy revealed 77% (Octreoscan 5/18; 99mTc-V-DMSA 9/18), surgical palpation 55% and conventional imaging methods (CT, sonography) only 38% of all lesions detected intraoperatively by the hand-held gamma probe. In summary, this preliminary data show that intraoperative hand-held gamma probe detection of microscopic and occult endocrine tumors is feasible and more sensitive than external scintigraphy and conventional imaging.
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PMID:[Pre- and intraoperative localization of neuroendocrine tumors]. 927 12

Early diagnosis of metastases of medullary thyroid carcinoma (MTC) provides the optimal condition for curative outcome. The aim of this study was to appraise the detection of metastases in patients with recurrent MTC using [111In-DTPA-d-Phe1]-pentetreotide and pentavalent technetium-99m dimercaptosuccinic acid [99mTc(V)-DMSA] in comparison with histopathological findings. Eighteen MTC patients with persistently elevated tumour marker (calcitonin, carcinoembryonic antigen) levels underwent somatostatin receptor scintigraphy using [111In-DTPA-d-Phe1]-pentetreotide (222 MBq) with early (4 h after injection) and delayed (24 h) whole-body scans and single-photon emission tomography (SPET) imaging. Metabolic whole-body and SPET imaging using 500 MBq 99mTc(V)-DMSA was performed 4 h after injection. Metabolic and receptor imaging revealed 51 sites of focal accumulation in the 18 patients investigated. Comparison with histological findings revealed that metabolic and receptor imaging had a sensitivity of 84% for the diagnosis of MTC. Using [111In-DTPA-d-Phe1]-pentetreotide, SPET discovered four lymph node metastases in two patients in whom planar views had previously identified only one lymph node metastasis, and provided no new information in the other 16 patients. In comparison, SPET studies [using 99mTc(V)-DMSA] additionally localized eight lymph node metastases in four patients and confirmed the diagnosis of hepatic metastases (n=5) in another patient in whom conventional imaging modalities and planar views had previously detected only three liver metastases. Overall, lesion detection sensitivities for 99mTc(V)-DMSA and [111In-DTPA-D-Phe1]-pentetreotide were 69% and 29%, respectively. Five surgically removed foci were adjudged false-positive with respect to MTC metastases. False-positve results were caused by lymphadenitis, an enchondroma and a pheochromocytoma (histologically proven). The smallest lesion identified by metabolic imaging was a 6 mm in diameter lymph node metastasis located in the upper mediastinum. Somatostatin receptor scintigraphy only demonstrated tumour sizes more than 1 cm in diameter. These preliminary results suggest that the combination of metabolic [99mTc(V)-DMSA] and receptor ([111In-DTPA-D-Phe1]-pentetreotide) imaging is more sensitive for tumour localization in patients with recurrent MTC than the use of only one radiopharmaceutical. However, neither 99mTc(V)-DMSA nor [111In-DTPA-D-Phe1]-pentetreotide is specific for MTC and false-positive scintigraphic findings have to be considered. Furthermore, somatostatin receptor scintigraphy cannot visualize small tumour sites (<1 cm). Further studies are needed to evaluate the role of combined metabolic and receptor imaging in the management of patients with recurrent MTC.
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PMID:Comparison of metabolic and receptor imaging in recurrent medullary thyroid carcinoma with histopathological findings. 1004 54

Medullary thyroid carcinoma (MTC) originates in the parafollicular cells (C cells) of the thyroid, secreting both calcitonin and CEA. Genetic and biochemical testing allow early pre-clinical identification of familial forms. Sporadic MTC usually presents as a solitary palpable thyroid nodule and in most cases the definitive diagnosis is established only at the time of surgery. Nuclear medicine procedures, which play a minor role in the preoperative evaluation of MTC, are essential in postoperative follow-up to detect residual and/or recurrent tumor. A number of radiopharmaceuticals are able to visualize MTC lesions with considerable advantages in diagnosis and prognosis, some of them having also a therapeutic role. Among them, 99mTc[V]DMSA shows the highest diagnostic sensitivity and is considered by many authors the radiopharmaceutical of choice in the postoperative work-up of MTC. Radioiodinated MIBG, in spite of its high specificity has a poor sensitivity (30%); however it is useful for the identification of pheochromocytoma and, in patients showing MIBG uptake in tumoral lesions, high activities of 131I-MIBG may be used for therapy. 111In labeled octreotide detects lesions which express somatostatin receptors; a positive scintigraphic result seems to give also prognostic information (higher uptake in slow-growing lesions) and provides the basis for treatment with octreotide or lanreotide and 111In or 90Y-labeled octreotide analogues. Interesting perspectives are offered by 18F-FDG PET and monoclonal anti-CEA labeled antibodies; the latter may be also used for therapy.
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PMID:Role of nuclear medicine in the diagnosis and therapy of medullary thyroid carcinoma. 1137 May 45