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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although nonsecreting suprarenal embryonic remnants are frequently found in the urogenital tract, adenomatous transformation resulting in glucocorticoid excess is a rare phenomenon. We report a case of a 63-yr-old woman that presented with new-onset hirsutism, facial plethora, hypertension, centripetal obesity, and a proximal myopathy. The 24-h urinary free cortisol excretion rate was elevated, and the serum ACTH level was suppressed. The patient failed an overnight and low dose dexamethasone suppression test and did not respond to CRH stimulation. In light of the undetectable baseline morning ACTH levels and the blunt response to CRH, the diagnosis of corticotropin-independent Cushing's syndrome was made. Imaging studies revealed normal adrenal glands and enlargement of a left pararenal nodule incidentally observed 4 yr before the onset of symptoms. Dramatic resolution of symptoms was observed after surgical removal of the 3.5-cm mass. Pathological exam confirmed adrenocortical adenoma in ectopic adrenal tissue. The case reported here represents the unusual circumstance in which the development of adenomatous transformation of ectopic adrenal tissue has been prospectively observed with imaging studies. It illustrates the importance of considering ectopic corticosteroid-secreting tumors in the context of corticotropin-independent Cushing's syndrome.
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PMID:Corticotropin-independent Cushing's syndrome caused by an ectopic adrenal adenoma. 1094 1

We describe the first case of an adrenocortical-pituitary hybrid tumor causing Cushing's syndrome in a 17-yr-old boy. Adrenal vein sampling confirmed elevated secretion of both cortisol and ACTH precursors from a right adrenal mass, whereas pituitary ACTH levels, as determined by bilateral inferior petrosal sinus samples (IPSS), were unresponsive to CRH and equal to peripheral levels. There was no biochemical or histological evidence for a pheochromocytoma, but, rather, the tumor demonstrated lipid-rich clear cells characteristic of an adrenocortical adenoma. Immunohistochemical analysis revealed ACTH immunoreactivity and synaptophysin proteins in the tumor. Isolation of tumor cells by the novel technique of laser capture microdissection and subsequent RT-PCR showed expression of POMC messenger ribonucleic acid and cytochrome p450 enzyme messenger ribonucleic acid within the same cells. Finally, ultrastructural analysis provided ultimate proof for adrenocortical-pituitary hybrid cells exhibiting the characteristic vesicular mitochondria and abundant smooth endoplasmic reticulum of steroid cells and the typical secretory granules of corticotrophs within the cytoplasm of the same cells. The adrenocortical tumor expressed the pituitary transcription factor pituitary homeobox factor 1 and the steroidogenic factor 1. The intermingling of the centrally located ectodermally derived pituitary tissue with the mesodermally derived adrenocortical tissue in this adenoma suggests a hitherto unrecognized genetic and phenotypic plasticity within the hypothalamic-pituitary-adrenal axis.
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PMID:Adrenocortical-pituitary hybrid tumor causing Cushing's syndrome. 1139 64

In the group of 13 patients with Cushing's syndrome (CS) CRH test was performed by sampling the blood from peripheral vein and in eight patients also after inferior petrosal sinus catheterization (IPSC) to resolve the disease etiology. In the group of patients with Cushing's disease (CD, n = 11), which was proven by surgery and adenoma immunohistochemistry, 10/11 had in CRH test the significant increase of cortisol and ACTH in the peripheral blood. Among two patients with ectopic ACTH syndrome one had the significant increase of both hormones in CRH test. After IPSC the ratio of ACTH in the petrosal sinus and in the peripheral vein was significant in 4/8 patients before, and in 6/8 after CRH administration. The intersinus gradient was significant in 3/8 patients before, and in 4/8 after CRH test. According to our results we can conclude that the determination of ACTH in the blood from peripheral veins after CRH administration is a very sensitive method for differential diagnosis of CS, while the results after IPSC were less sensitive in our conditions than those described in the literature.
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PMID:[Importance of the CRH (corticotropin releasing hormone) test in the differential diagnosis of Cushing's syndrome]. 1172 9

Selective transsphenoidal microadenomectomy is the first line treatment of childhood Cushing's disease, with accurate preoperative localization of the corticotroph adenoma an important step in its investigation. Inferior petrosal sinus sampling (IPSS) for ACTH after CRH stimulation is a recognized investigation in adults, but there are few data in the pediatric age range. We report the relative contributions of IPSS and pituitary imaging in 11 patients, aged 10.7-18.8 yr, presenting with Cushing's disease. All underwent transsphenoidal surgery (TSS). IPSS was performed without complication. Sampling was from the inferior petrosal sinuses in 7 patients and the high jugular veins in 4 (patients 2, 4, 5, and 10). The central to peripheral ACTH (IPS/P) ratios were more than 2 (2.5-157.2) in 10 of 11 patients, confirming central ACTH secretion. In 3 patients with high jugular sampling, IPS/P ratio ranged from 2.5-21.1. In the fourth patient with high jugular sampling (IPS/P ratio, 0.95), a central adenoma was identified surgically, and the patient was cured after TSS. The interpetrosal sinus ACTH gradient (IPSG) was more than 1.4 (2.1-20.8) in 10 patients, indicating lateralization of ACTH secretion to the right side in 6 patients and to the left in 4. IPSG ratios were 2.1-8.5 in 3 patients with high jugular sampling. Pituitary imaging (computed tomography and or magnetic resonance imaging) was reported to identify an adenoma in 5 of 11 patients. At operation a tumor was visualized by the same surgeon in all 11 cases. In 9 patients with lateralization on IPSS, the correct side of the tumor was confirmed at surgery. In a 10th patient with a negative IPSG, a central tumor was present. Thus, IPSS gave a 91% prediction of correct tumor localization. In only 1 of 5 patients with an adenoma reported on pituitary imaging was this localization confirmed at surgery, a prediction rate of only 9%. After TSS, 8 patients were cured, 1 was in remission, and 2 required pituitary irradiation. In 73% of patients undergoing IPSS, localization of the adenoma was followed by surgical cure or remission. Pituitary scanning was therefore relatively unhelpful in localizing the adenoma. In experienced hands, however, IPSS was feasible in this age group, safe, and strongly predictive of the site of the adenoma, leading to a high rate of successful surgical outcome.
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PMID:Relative contributions of inferior petrosal sinus sampling and pituitary imaging in the investigation of children and adolescents with ACTH-dependent Cushing's syndrome. 1173 26

In 22 patients with ACTH-dependent Cushing's syndrome we have performed multiple ACTH evaluations, baseline and after ACTH-releasing hormone (CRH), during simultaneous bilateral inferior petrosal sinus sampling. The basal inferior petrosal sinus/periphery ratio for ACTH was > 2 in 11/22 patients, CRH challenge caused the appearance of an inferior petrosal sinus/periphery ratio > 3 in 6 other patients. An ACTH-secreting adenoma was surgically proven in 17 patients with ACTH inferior petrosal sinus/periphery ratio > 2 basally or > 3 after CRH and in 1 patient with an inferior petrosal sinus/periphery ratio < 2 basally or 3 after CRH. In 4 patients the very high peripheral ACTH levels, the inferior petrosal sinus/periphery ratio and the lack of ACTH increase after CRH indicated the presence of an ectopic ACTH syndrome. An ACTH intersinus gradient > 1.4 was found in 11 patients. Among these patients the adenoma was correctly localised in 6 and wrongly in 5 patients. In conclusion, the diagnostic accuracy of the inferior petrosal sinus sampling was of 95.4% (21/22 cases) considering basal and CRH-stimulated ACTH levels. The multiple basal ACTH evaluation does not seem to be necessary associated with CRH-test, but may be helpful in some cases.
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PMID:[Simultaneous and bilateral catheterization of inferior petrosal sinuses in the diagnosis of Cushing's syndrome: basal multiple sampling and after ACTH-releasing hormone test]. 1176 85

Cushing's syndrome invariably presents with a classical phenotype comprising central adiposity, prominence of dorsal, supraclavicular and temporal fat pads, bruising, abdominal striae, proximal myopathy, and hypertension. We report the case of a 20-yr-old student with pituitary-dependent Cushing's syndrome who was spared this classical phenotype because of a defect in the peripheral conversion of cortisone to cortisol. She presented to her general practitioner with secondary amenorrhea. Clinical examination revealed normal fat distribution (body mass index, 20.9 kg/m(2)), absence of hirsutism, myopathy, or bruising; her blood pressure ranged from 115/70 to 122/82 mm Hg. She was investigated for biochemical hypercortisolemia because of a mildly elevated random circulating cortisol (serum cortisol, 661 nmol/liter). Cushing's syndrome was confirmed on the basis of repeatedly elevated urinary free cortisols (831-1049; reference range, <350 nmol/24 h), failure of low-dose dexamethasone suppression (611 nmol/liter) and loss of circadian cortisol secretion. Investigations suggested Cushing's disease; there was suppression after high-dose dexamethasone (<20 nmol/liter) and a 950% increase in ACTH after stimulation with CRH. Pituitary magnetic resonance imaging revealed a 3-mm adenoma within the pituitary gland. Urinary corticosteroid metabolites were analyzed by gas chromatography-mass spectrometry and demonstrated a decreased THF+allo-THF/THE ratio of 0.66 (mean +/- SE in Cushing's disease, 1.74 +/- 0.24) suggesting a defect in 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), an enzyme that converts the inactive glucocorticoid cortisone to active cortisol. Transphenoidal microadenomectomy was performed, and histology confirmed the diagnosis of a corticotroph adenoma. Postoperatively, serum cortisol was undetectable and replacement therapy was commenced. Subsequent investigations revealed a significantly impaired ability to convert an oral dose of cortisone acetate (25 mg) to cortisol, reduced serum cortisol to cortisone ratios, and a reduced serum half-life for cortisol (57.3 min). These results provide strong evidence for a partial defect in 11beta-HSD1 activity and concomitant increase in cortisol clearance rate. We have described a case of Cushing's disease that failed to present with a classical phenotype, and we postulate that this is due to a partial defect of 11beta-HSD1 activity, the defect in cortisone to cortisol conversion increasing cortisol clearance and thus protecting the patient from the effects of cortisol excess. This observation may help to explain individual susceptibility to the adverse effects of glucocorticoids.
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PMID:Absence of Cushingoid phenotype in a patient with Cushing's disease due to defective cortisone to cortisol conversion. 1178 23

A growing number of physiological and pathophysiological processes have been shown to be influenced by leptin apart from its first recognised role as a modulator of hypothalamic appetite and weight control centers. We investigated the presence and pattern of distribution of leptin mRNA and the mRNA of the long isoform of the leptin receptor in the normal pituitary and in different types of pituitary adenomas. We also studied leptin secretion from human pituitary tumors in culture, and the in vitro pituitary hormone release following stimulation with human leptin. Leptin mRNA expression was detected at a low level of expression in 50% of tumors but in none of the normal pituitaries. By immunohistochemistry, leptin was present in occasional scattered cells in the normal pituitary and in pituitary tumors. The leptin receptor long isoform was detected in the majority (65%) of pituitary tumors and in all normal pituitaries. It did not segregate with any particular tumor type, and varying levels of expression were detected between the tissues studied. 34% of pituitary adenomas showed leptin release into the incubation media during in vitro culture. Leptin mRNA, the mRNA of the long isoform of the receptor, or in vitro leptin release, did not correlate with tumor type or with any of the other pituitary hormones released. In vitro leptin stimulation of pituitary tumors caused stimulation of FSH and a-subunit secretion from a non-functioning adenoma and TSH secretion from a somatotroph adenoma. As the co-localisation of ACTH and leptin in corticotroph cells was previously suggested, we investigated whether in vivo ACTH release is accompanied by a simultaneous plasma leptin level rise (i) in peripheral plasma samples after food intake-induced ACTH rise in healthy obese and nonobese individuals and (ii) in petrosal sinus samples after CRH injection in Cushing's disease patients. Our data suggest that a rise in ACTH levels is not accompanied by detectable rise in leptin levels in peripheral and in petrosal sinus blood samples. In summary, leptin is synthesized and stored within the pituitary and may modulate other pituitary hormone secretion, although probably it does not contribute to plasma leptin level changes. Pituitary leptin may therefore be a novel paracrine regulator of pituitary function.
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PMID:Leptin in pituitary adenomas--a novel paracrine regulatory system. 1182 7

The classical trias in Cushing's disease, normal or moderately elevated plasma ACTH, significant suppression of cortisol in the high-dose dexamethasone test, and stimulation of ACTH and cortisol in the CRH test, confirms the diagnosis in most cases. However, as a referral centre for complex Cushing's disease cases, we are confronted with problems in the differentiation of pituitary and ectopic Cushing's syndrome and with problems in the localisation of minute ACTH-secreting pituitary adenomas. In this study, cavernous sinus sampling (CSS) was evaluated as a diagnostic tool in complex Cushing's disease cases. Thirty-five patients were transferred to our unit for the treatment of Cushing's disease between January 1999 and August 2000. Of those, 17 patients (including five children) had the combination of equivocal results in endocrinological testing and negative MRI prior to admission. In these cases, CSS was performed preoperatively to confirm the diagnosis and to obtain further information about the localisation of pituitary microadenomas. Twelve of these 17 patients showed the classical trias for Cushing's disease after equivocal tests were repeated. A central-peripheral gradient was also found using CSS. In ten of the 11 patients, where CSS could be successfully performed, the lateralisation of the ACTH-adenoma was correctly predicted (91%). In the eleventh case, a right ACTH-gradient was found in a stalk tumour. In one patient (a child), the catheterisation of the cavernous sinus failed due to anatomical reasons. Eleven of these 12 patients successfully underwent transnasal adenomectomy. In two of the 17 patients, active Cushing's syndrome was excluded. In the remaining three cases, ectopic Cushing's syndrome was suspected based on CSS results. Therefore, these patients did not undergo pituitary exploration. In complex cases, we recommend CSS for diagnostic purposes, especially for the localisation of ACTH-secreting microadenomas within the pituitary. In our experience, CSS has a higher accuracy than inferior petrosal sinus sampling (IPSS) in the localisation of ACTH-adenomas.
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PMID:Cavernous sinus sampling in selected cases of Cushing's disease. 1239 31

Cushing's disease (CD) presents a marked female preponderance, but whether this skewed gender distribution has any relevance to the presentation and outcome of CD is not known. The aim of the present study was the comparison of clinical features, biochemical indices of hypercortisolism, and surgical outcome among male and female patients with CD. The study population comprised 280 patients with CD (233 females, 47 males) collected by the Italian multicentre study. Epidemiological data, frequency of clinical signs and symptoms, urinary free cortisol (UFC), plasma ACTH and cortisol levels, responses to dynamic testing, and surgical outcome were compared in female and male patients. Male patients with CD presented at a younger age, compared with females (30.5 +/- 1.93 vs. 37.1 +/- 0.86 yr, P < 0.01), with higher UFC and ACTH levels (434.1 +/- 51.96 vs. 342.1 +/- 21.01% upper limit of the normal range for UFC, P < 0.05; 163.9 +/- 22.92 vs. 117.7 +/- 9.59% upper limit of the normal range for ACTH, P < 0.05). No difference in ACTH and cortisol responses to CRH, gradient at inferior petrosal sinus sampling, and cortisol inhibition after low-dose dexamethasone was recorded between sexes. In contrast, the sensitivity of the high-dose dexamethasone test was significantly lower in male than in female patients. Of particular interest, symptoms indicative of hypercatabolic state were more frequent in male patients; indeed, males presented a higher prevalence of osteoporosis, muscle wasting, striae, and nephrolitiasis. Conversely, no symptom was more frequent in female patients with CD. Patients with myopathy, hypokalemia, and purple striae presented significantly higher UFC levels, compared with patients without these symptoms. Lastly, in male patients, pituitary imaging was more frequently negative and immediate and late surgical outcome less favorable. In conclusion, CD appeared at a younger age and with a more severe clinical presentation in males, compared with females, together with more pronounced elevation of cortisol and ACTH levels. Furthermore, high-dose dexamethasone suppression test and pituitary imaging were less reliable in detecting the adenoma in male patients, further burdening the differential diagnosis with ectopic ACTH secretion. Lastly, the postsurgical course of the disease carried a worse prognosis in males. Altogether, these findings depict a different pattern for CD in males and females.
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PMID:Gender-related differences in the presentation and course of Cushing's disease. 1267 38

The present study reports a rare case of full-blown Cushing's disease several years after an episode of pituitary apoplexy. A 60 year-old woman complained of muscular weakness and generalized malaise. Ten years ago she had an episode of pituitary apoplexy. Diabetes mellitus was diagnosed at age 56, and thereafter she had been controlled her plasma glucose with diet therapy and oral hypoglycemic agents. She exhibited cushingoid feature of moon face and central obesity. Both plasma ACTH and serum cortisol levels were elevated to 170 pg/ml and 19.6 microg/dl, respectively. Dexamethasone suppression test showed that a large dose of 8 mg dexamethasone, but not a small dose of 2 mg, suppressed the pituitary-adrenocortical axis. CRH and methyrapone caused increases in plasma ACTH and serum cortisol levels. Brain T(1)-weighted magnetic resonance imaging depicted a low signal of pituitary tumor, which was not enhanced by gadolinium. The pituitary tumor was removed by transsphenoidal adenomectomy, and immunohistochemistry revealed an ACTH-producing adenoma. The evidence suggested the possibility that the two pituitary tumors with dormant period of several years were a recurrence of ACTH-producing tumors in the present patient.
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PMID:Full-blown Cushing's disease after an episode of pituitary apoplexy. 1461 5


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