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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The case was a 33-year-old woman with hypertension and hypokalemia, who presented depression of renin activity and the abnormal elevation of plasma deoxycorticosterone (DOC) and 11-deoxycortisol on laboratory tests. After admission, abdominal CT scan, 131I-adosterol scintigram and adrenal venogram revealed a tumor in the left adrenal, which histologically seemed to be benign. When the tumor was resected, blood pressure and all the biochemical data returned to normal range. DOC and 11-deoxycortisol levels in the tumor were abnormally elevated as compared with those in the normal adrenal tissue. These findings suggested that the abnormal elevation of hormone levels resulted from depression of 11 beta-hydroxylase. Though numerous adrenal tumors have been documented, we rarely encounter an apparently benign adrenal tumor that produces 2 kinds of hormones. This seemed to be the first case of benign adrenal tumor in which both DOC and 11-deoxycortisol were elevated.
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PMID:[A case of the benign adrenal adenoma with remarkably high concentrations of deoxycorticosterone and 11-deoxycortisol]. 262 46

We employed a novel immunoradiometric assay to measure plasma levels of active renin and prorenin in physiologic and pharmacologic studies designed to characterize renin biosynthesis and processing in response to both chronic and acute stimuli of renin secretion in normal human subjects. Stimulation of renin secretion with prolonged dietary sodium restriction or amiloride resulted in marked increases in the plasma levels of prorenin, active renin, and plasma renin activity (PRA); suppression of renin secretion with indomethacin resulted in parallel decreases in prorenin, active renin, and PRA. In contrast, acute stimulation with upright activity or administration of an angiotensin-converting enzyme inhibitor, which increased active renin and PRA from 2- to 15-fold, had no effect on prorenin levels. Based on studies in cultured human juxtaglomerular tumor cells, it has been proposed that prorenin is secreted constitutively whereas active renin is stored in and released from secretory granules through a regulated pathway. Our studies are consistent with such a model: the parallel changes in active renin and prorenin with experimental maneuvers of long duration suggest that both the constitutive and regulated pathways are altered under these conditions. The increase in active renin levels in the absence of a change in prorenin that occurs in response to acute stimuli presumably represents the release of preformed active enzyme that is stored in secretory granules.
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PMID:Response of plasma prorenin and active renin to chronic and acute alterations of renin secretion in normal humans. Studies using a direct immunoradiometric assay. 264 35

Although renin-secreting tumors are rare, they must be considered in the differential diagnosis of hypertension associated with hypokalemia, which occurs commonly in the hypertensive population. The finding of an ovarian renin-secreting tumor emphasizes the potential importance of the ovary as an extrarenal source of renin; the local ovarian renin-angiotensin system may play a key role in reproductive function by regulating vascular reactivity, local blood flow, steroidogenesis and other physiologic effects. In the illustrative case presented, a renin-secreting ovarian leiomyosarcoma was obtained from a women who presented with hypertension and hypokalemia. Plasma prorenin levels were markedly elevated. Tumor excision was quickly followed by a fall in prorenin levels and tumor recurrence was accompanied by an increase in prorenin levels. Active renin concentration in the tumor homogenates was similar to that found in kidney homogenates while the tissue prorenin concentration was approximately 20 times that found in kidney tissue. When cultured for up to 4 weeks, ovarian tumor cells secreted greater than 95% prorenin. Immunoblot analysis demonstrated that tumor renin had a molecular weight of 47,000, similar to that of human recombinant prorenin. Immunohistochemical staining of tumor tissue with antibodies against human renal renin at the electron microscopic level demonstrated the presence of renin primarily in membrane-bound vesicles and rarely in dense-core secretory granules. These findings suggest that prorenin in this ovarian tumor was secreted by the constitutive pathway, which is mediated by these amorphous vesicles.
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PMID:Extrarenal renin-secreting tumors: insights into hypertension and ovarian renin production. 267 94

Juxtaglomerular cell tumor of the kidney is an uncommon neoplastic cause of surgically curable hypertension. We report a case of erythrocytosis due to elevated serum erythropoietin with a renin secreting juxtaglomerular cell tumor.
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PMID:Juxtaglomerular cell tumor with elevation of serum erythropoietin. 268 72

Extrarenal renin has been identified in a number of tissues, including the brain, the submaxillary gland, uterus, ovary, vascular endothelium, testes, pituitary gland, and the adrenal cortex. In some tissues, including the adrenal cortex, all of the components of the renin-angiotensin system have been identified; however, no specific physiologic role has been clearly demonstrated for these extrarenal renin-angiotensin systems. We have studied the role of the renin-angiotensin system in the adrenal cortex of the rat and have found that renin is localized and synthesized in the zona glomerulosa cells. Its production can be influenced by alterations in electrolyte balance, as well as the genetic background of the rat. In adrenal capsular explant cultures, a converting enzyme inhibitor can lower angiotensin II production and reduce the stimulation of aldosterone by potassium, suggesting that this system is involved in the aldosterone response to potassium. In addition to rat adrenals, renin has been identified in human adrenal tissue and human adrenal tumors, including aldosteronomas, and a patient with hypertension has been reported to have an adrenal tumor that appeared to be secreting renin into the circulation.
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PMID:Adrenal renin: a possible local regulator of aldosterone production. 269 84

A 37-year-old woman presented with hyperaldosteronism, suppressed renin levels, and a left adrenal mass on CT scanning. Selective adrenal venous sampling indicated a marked rise of the aldosterone level in the right adrenal vein, while the level in the left vein was low. On laparotomy, an aldosterone producing adenoma (APA) of 12x10x5 mm in size was found in the right adrenal gland and was resected, while the left mass was left in situ. The post-operative course showed normalization of both the clinical and biochemical features of primary aldosteronism, with no sign of recurrence or of enlargement of the remaining adrenal mass in 2.5 years of follow up, suggesting the possible coexistence of a "non-functioning" tumor. This case demonstrates the importance of adrenal venous sampling for the localization of APA particularly since the presence of the APA may be masked by a visualized but unrelated adrenal mass.
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PMID:Possible association of aldosterone producing adenoma and non-functioning adrenal tumor. 272 41

A 47-year-old female presented with hypertension, hypokalaemia, low plasma renin, high plasma aldosterone and was found to have a left adrenal tumour 4 cm in diameter by computerized tomography. Detailed biochemical studies showed high plasma levels of 11-deoxycorticosterone and corticosterone in addition to aldosterone and 18-hydroxycorticosterone. Basal 11-deoxycorticosterone levels were particularly high. Corticosterone, 18-hydroxycorticosterone and aldosterone concentrations were abnormally sensitive to infusions of ACTH and angiotensin II. Plasma cortisol and assays for sex hormones were normal although there was evidence that cortisol derived from the neoplasm. At operation a well-differentiated adrenocortical carcinoma weighing 50 g (56 X 30 X 36 mm) was removed. There was no evidence of metastases following surgery. Adrenal function returned to normal. Review of the literature suggests that adrenocortical carcinoma should be suspected in patients who otherwise have typical features of Conn's syndrome, but whose tumours are more than 3 cm in diameter. Measurement of steroids such as 11-deoxycorticosterone in addition to aldosterone is recommended since abnormally high values may also help to distinguish between hyperaldosteronism due to adenoma and carcinoma. Previously reported cases of isolated aldosterone production by a carcinoma cannot be substantiated.
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PMID:Hypermineralocorticoidism due to adrenal carcinoma: plasma corticosteroids and their response to ACTH and angiotensin II. 282 95

Two infants with renal tumors and associated hypertension are presented. By using an antibody to purified human renal renin, the sites of renin production were localized immunohistochemically in each tumor. The first case was a 9-month-old girl with Beckwith-Wiedemann syndrome. She presented with bilateral renal masses and hypertension (140/90 mm Hg). Following a left nephrectomy and chemotherapy and radiotherapy, her BP returned to normal. Her tumor was a Wilms' tumor of favorable histology, composed predominantly of glomeruloid structures. Renin was localized within a part of these neoplastic glomeruloid bodies. We therefore designated this as a Wilms' tumor with glomeruloid differentiation having primary reninism. The second case was a 24-day-old girl with hypertension (140/70 mm Hg). A renal tumor was found and successfully removed. Her BP returned to normal. The tumor was histologically confirmed as a congenital mesoblastic nephroma. By indirect immunoperoxidase staining, renin was localized only in the hypertrophied juxtaglomerular cells adjacent to the residual glomeruli entrapped by the tumor. None was seen in the tumor cells. We concluded that this was a case of secondary reninism--a case of hypertension secondary to the local ischemia at the entrapped glomeruli.
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PMID:Demonstration of both primary and secondary reninism in renal tumors in children. 283 60

Besides the juxtaglomerular cell tumors, tumors may be responsible for a primary hyperreninism syndrome. Strict criteria allow to assert that the tumor cells themselves are involved in ectopic renin secretion. They are as follows:--measurement of the renin in the blood and in tumoral tissue extracts with assessment of active anf inactive renin,--absence of any other cause of hyperreninism,--regression of the hyperreninism when the tumor is removed, and possibly recurrence when metastases appear,--demonstration of renin antigen in tumor cells by immuno-histochemistry and more recently detection of renin messenger RNA using in situ hybridization with human renin probe. About 40 cases of these tumors have been described. They are mainly renal tumors: nephroblastomas (29 cases), adenocarcinomas (7 cases) and other rare tumors. Among extrarenal tumors, it has been observed epithelial tumors (broncho-pulmonary cancers, ovarian, fallopian and pituitary tumors), soft tissue tumors (alveolar sarcomas. epithelioid sarcoma, hemangiopericytoma, leiomyosarcoma). It has not been demonstrated that tumor cells from pheochromocytoma could be themselves involved in renin production.
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PMID:[Tumor syndromes with inappropriate renin secretion. Diagnostic criteria and review of published cases]. 284 Sep 23

Congenital mesoblastic nephroma (CMN) is the most common renal tumor of early infancy. It is usually evident at birth as an abdominal mass and is composed of spindle-shaped cells resembling smooth muscle cells and fibroblasts. There is macroscopic and microscopic infiltration of the surrounding kidney and entrapped tubules and glomeruli are common at the edge of the tumor. In this report, we describe a case of CMN associated with hyperreninaemia and hypertension. We examined the tumor from this case and 11 other cases for the presence of renin using a polyclonal antibody to human kidney renin. Hypertension was present in three of four additional cases for which records were available. Immunoreactive renin was present in ten of the 12 cases studied. In all of these cases, intense staining was present in vessels within the areas of the trapped cortex. In seven cases, renin was identified in the walls of vessels within the tumor itself without identifiable adjacent cortical structures. These findings indicate that CMN may often be associated with primary reninism in early infancy.
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PMID:Renin in mesoblastic nephroma: an immunohistochemical study. 284 23


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