Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

Pheochromocytomas may produce several vasoactive peptides. We studied a 39-year-old man who presented with paroxysmal flushing and abdominal pain with normal blood pressure. Laboratory and radiologic studies established the diagnosis of right adrenal pheochromocytoma, and histologic and ultrastructural examination showed the tumor to be a typical pheochromocytoma. Tissue culture yielded large quantities of norepinephrine and epinephrine. However, immunohistochemical studies, tissue assays, and in vitro cultures documented production of several peptides, including calcitonin gene-related peptide and vasoactive intestinal polypeptide in tumor cells. The patient has been asymptomatic after tumor resection. Production of multiple peptides by this tumor may account for the flushing and lack of hypertension, despite elevated catecholamine levels in this patient.
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PMID:Pheochromocytoma producing multiple vasoactive peptides. 173 41

Pheochromocytoma is a catecholamine secreting tumor which has been traditionally considered as a potentially curable cause of hypertension. However, the existence of malignant pheochromocytomas as well as the problem which the recurrence of benign pheochromocytomas present, make the eradication of this tumor more complicated. It is note worthy the difficulty in localizing recurrent pheochromocytomas as well as the prognostic interest that presents the possibility of differentiating between recurrence and metastasis. We refer the case of a female patient suffering benign adrenal pheochromocytoma, who, 10 years it was surgically removed, presented a relapse of symptoms, and was diagnosed of extra-adrenal pheochromocytoma, in Zuckerkandl organ. The importance of performing a long term post-surgical follow-up in these patients is stressed.
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PMID:[Late recurrence in pheochromocytoma: need for a long term follow up]. 174 5

89 patients were operated on for pheochromocytoma. 61 patients (37 women and 24 men) were available for extended follow-up. The final survey, performed 79.1 +/- 66.9 months postoperatively, provided data on survival, blood pressure tumor recurrence, malignant metastatic lesions, cardiovascular complications and coexisting diseases. There were 4 deaths during the follow-up period, including 2 instances of malignant pheochromocytoma. Permanent normalization of blood pressure was achieved in 38 patients (62.3%). This hypotensive effect was noted in 79.2% of patients with preoperative paroxysmal hypertension and in 40.8% of those with sustained hypertension. Permanent or re-developing postoperative hypertension was noted in 23 (37.7%) patients. This includes 4 cases of malignant pheochromocytoma, 4 cases of recurrent benign pheochromocytoma and 15 cases of essential hypertension. Cardiovascular complications during follow-up were rare and concerned the patients with essential hypertension diagnosed postoperatively.
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PMID:Long term follow-up after surgical removal of pheochromocytoma--observations in 61 patients. 176 Aug 86

The case of a 47-year-old woman affected with right adrenal pheochromocytoma and right renal artery stenosis is presented. The concurrence of these two diseases is rarely reported in the literature, as shown by the review presented. Nevertheless, this association carries some problems as far as diagnosis is concerned, because missing renal artery lesion can lead to the maintenance of the hypertensive disease after surgical excision of the adrenal pheochromocytoma. Anyway, the extensive use of angiography is not justified for pheochromocytoma alone, because an excellent imaging of the mass can be achieved by means of non-invasive technologies, such as CT, echo B-mode, NMR. A careful evaluation of clinical features and non-invasive imaging and the presence of elevated plasma renin activity, although not determinant in surgical decision making, can support the suspicion of renovascular hypertension in the presence of pheochromocytoma and suggest to carry out renal angiogram and selective renal veins reninemia.
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PMID:[Association of pheochromocytoma and renovascular hypertension]. 176 62

During the past 20 years (1970-90), we had 24 patients with pheochromocytoma: 19 diagnosed clinically and 5 post-mortem. Their ages ranged from 17 to 74 (mean, 43.2 years). Males (n = 14) outnumbered females (n = 10), a 1.41:1 M:F ratio. A majority were symptomatic (95%), with a typical triad of headaches, palpitations and diaphoresis. Most frequent finding was hypertension (95%). It was sustained in 60% and paroxysmal in 35%. In 6 patients (25%) pheochromocytomas were bilateral, all familial. Fifteen were solitary adrenal tumors (63%); 3 (12.5%) were extra-adrenal: 2 intra-abdominal, and 1 cardiac paraganglioma of right atrium. Of 6 familial cases, 4 were associated to Von Hippel-Lindau (VHL) disease, while 2 were multiple endocrine neoplasia (MEN-II) patients. All familial cases were bilateral and in the adrenals. There were no malignancies. Among the 19 clinical cases pre-operative Dx was made by positive urine VMA or catecholamines urine levels: (95 and 100% sensitivity respectively). Preoperative visualization by CT or MRI was done in 62% of the most recent patients. In 5 earlier cases the diagnosis was made post mortem: 3 died of cerebral hemorrhage, 1 with a pons infarct and 1 with congestive heart failure (CHF). There were 2 post-operative deaths and another died 13 years later from thyroid medullary carcinoma. Of the 19 operated, 13 (68%) were cured. Thus pheochromocytomas retain considerable morbidity and some mortality. These rare tumors constitute a clinical diagnostic challenge yet a rewarding therapeutic experience for the alert physician.
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PMID:Pheochromocytoma: a twenty year experience at the University Hospital. 177 16

Pheochromocytomas are often unnoticed, and diagnosis is performed on autopsy examination, or more rarely it is noticed during surgery or abdominal exam for a different reason. In many of these patients the lack of hypertension is a characteristic feature. We contribute a singular case of a patient with pheochromocytoma found by chance during an abdominal exam and which in spite of secreting noradrenaline, did not provoke hypertension or other symptoms. We review literature on this stage form of presentation and the different physio-pharmacological hypothesis which could condition the absence of clinical manifestations. We discuss the preoperative management in patients without hypertension.
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PMID:[A clinically unsuspected pheochromocytoma]. 180 Oct 71

During three consecutive days of prazosin treatment in a patient with pheochromocytoma, urinary catecholamine metabolite levels were correlated with plasma renin activity. Suppression of renin plasma activity resulted in sustained hemodynamic and clinical improvement, while no remarkable changes were observed in urinary catecholamine metabolite levels. This suggests that prazosin may interrupt the vicious cycle of worsening hypertension provoked by further activation of the renin-angiotensin system mediated by excessive circulating catecholamines.
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PMID:Prazosin's effect in high renin hypertension complicating pheochromocytoma. 181 Jun 94

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

In practice, some of the major problems for the physician who treats hypertension are patients who are resistant to treatment or who have other complicating risk syndromes. Therefore the overall efficacy of an antihypertensive agent must include an assessment of effect in patients with serious ancillary problems. In this article, doxazosin is reviewed for its efficacy in the treatment of severe essential hypertension and specific complications or conditions of mild or moderate essential hypertension, namely, left ventricular hypertrophy, hyperlipidemia, noninsulin-dependent diabetes mellitus, renal insufficiency, pheochromocytoma, chronic obstructive pulmonary disease, peripheral vascular disease, and smoking. Doxazosin is particularly efficacious in many specific subgroups of patients with hypertension, and the results of relevant studies are discussed.
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PMID:Efficacy of doxazosin in specific hypertensive patient groups. 182 52


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