11/303. Preoperative short-term administration of octreotide for facilitating transsphenoidal removal of invasive growth hormone-secreting macroadenomas.The somatostatin analog octreotide was administered prior to transsphenoidal surgery in three patients with tumors that extended to the suprasellar space and one side of the cavernous sinus. octreotide, 100 micrograms twice a day, was subcutaneously injected for 2 weeks. octreotide administration reduced the serum growth hormone (GH) levels in these patients from 82 to 22 ng/ml, from 148 to 12 ng/ml, and from 129 to 9 ng/ml. The tumor size shrank by about 50%, and the suprasellar extension disappeared in two patients. The main tumor was sharply dissected from the normal pituitary gland at surgery. Intracavernous portions were removed using a curette. Postoperatively, GH levels were less than 5 ng/ml in two patients, and 8.5 ng/ml in one patient. Follow-up magnetic resonance imaging revealed a small residual tumor in one side of the cavernous sinus in all patients. Follow-up GH levels were less than 5 ng/ml in one patient, and less than 2 ng/ml in two patients treated with bromocriptine. Preoperative administration of octreotide for 2 weeks reduced tumor volume and allowed near-total surgical resection of invasive macroadenomas without compromising the treatment course. Residual tumor due to intracavernous extension can be managed with bromocriptine or gamma knife radiosurgery.- - - - - - - - - - ranking = 1keywords = pituitary, pituitary gland, gland (Clic here for more details about this article) |
12/303. Osseous metaplasia in a growth hormone-secreting pituitary adenoma.A case of growth hormone-secreting adenoma of the pituitary gland showing osseous metaplasia is described in a 56-year-old acromegalic female. The tumor was composed of nests of densely granulated cells separated by and intermixed with calcifications, trabeculae of mature bone and fat. Calcifications are seldom found in pituitary adenomas. In rare instances, calcium deposits can be prominent enough to lead to the formation of pituitary stones and bone which replace the entire tumor mass. Analogously with metaplastic meningiomas, we propose using the term metaplastic adenoma to define cases with osseous metaplasia in order to distinguish between lesions containing bone from the more frequently seen calcified adenomas.- - - - - - - - - - ranking = 6.4085154728817keywords = pituitary, pituitary gland, gland (Clic here for more details about this article) |
13/303. Ultrastructural and immunoelectron microscopic study of three unusual plurihormonal pituitary adenomas.Monomorphous pituitary adenomas expressing several hormones by immunocytochemistry are common, whereas adenomas displaying multiple immunoreactivities and consisting of more than one morphologic cell types are rare. Three such unusual pituitary adenomas, surgically removed from two patients with acromegaly and one patient with hyperprolactinemia, were investigated by histology, immunocytochemistry, transmission electron microscopy, as well as immunoelectron microscopy using double immunogold labeling. Immunocytochemistry revealed variable degrees of immunoreactivities for growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (beta-TSH), and alpha-subunit of glycoprotein hormones in all three tumors. The three adenomas consisted of phenotypically diverse cell populations as documented by transmission electron microscopy. In addition to monohormonal GH cells, immunoelectron microscopy demonstrated numerous cells colocalizing GH and PRL or GH and beta-TSH, and rarely PRL and beta-TSH in tumors of acromegalics. The adenoma causing hyperprolactinemia consisted chiefly of mammosomatotrophs colocalizing PRL and GH, whereas beta-TSH labeling was scant. The three tumors in the study were selected from a cluster of five plurimorphous plurihormonal adenomas received from the same locale where they accounted for an unprecedented 21% of adenomas producing GH and/or PRL. The enhanced susceptibility to develop plurimorphous adenomas of the acidophil cell line may have a genetic basis in the stable population the patients came from.- - - - - - - - - - ranking = 5.4085154728817keywords = pituitary (Clic here for more details about this article) |
14/303. acromegaly and papillomatosis: difficult intubation and use of the airway exchange catheter.We describe the anaesthetic management of a patient with acromegaly scheduled for transsphenoidal resection of a pituitary tumour who was found at intubation to have coexisting laryngeal papillomatosis. Oral intubation was impossible using both direct and fibreoptic techniques. Nasal fibreoptic intubation was successful but precluded the transsphenoidal approach to surgery. A Cook Airway Exchange Catheter [Cook (UK) Ltd, Monroe House, Letchworth SG6 1LN] was used with a Negus bronchoscope to convert to oral intubation and allow completion of surgery without resort to tracheostomy.- - - - - - - - - - ranking = 0.90141924548029keywords = pituitary (Clic here for more details about this article) |
15/303. Pituitary adenoma with neuronal choristoma: a report of two rare cases.Two rare cases of pituitary adenoma with neuronal choristoma are described. Both patients were female and presented with features of acromegaly with elevated growth hormone and prolactin levels. Radiologically, both lesions were predominantly intrasellar in location with extension into suprasellar region, but hypothalamus was not involved. Histopathological examination revealed a mixture of chromophobe pituitary adenoma cells and neuronal cells. In both cases, the adenoma component was positive for growth hormone and prolactin. Interestingly, immunopositivity for alpha-subunit, cytokeratin and prolactin was seen in the adenoma and neuronal cells in one case. Our findings support the hypothesis that the neuronal cells possibly arise from adenoma cells as a result of metaplasia.- - - - - - - - - - ranking = 1.8028384909606keywords = pituitary (Clic here for more details about this article) |
16/303. Pituitary somatotroph adenoma producing growth hormone (GH)-releasing hormone (GHRH) with an elevated plasma GHRH concentration: a model case for autocrine and paracrine regulation of GH secretion by GHRH.An acromegalic patient with a pituitary somatotroph adenoma associated with an extremely elevated plasma GHRH concentration is presented. The preoperatively high concentration of plasma GHRH returned to the normal level after successful removal of the adenoma. GHRH production and GHRH gene expression were confirmed in the adenoma by studies including immunohistochemistry and in situ hybridization. Expression of GHRH receptor messenger ribonucleic acid was verified by in situ hybridization. Immunohistochemical double staining for GH and GHRH revealed their colocalization in single adenoma cells. These findings confirmed the autocrine or paracrine regulation of GH production by endogenous GHRH from the adenoma cells. GHRH synthesis in the pituitary gland has recently been demonstrated, however, there have been no previous reports of a GHRH-producing pituitary somatotroph adenoma associated with an elevated plasma GHRH concentration. The existence of this GHRH-producing adenoma suggests a possible role of locally generated GHRH in the progression of somatotroph adenomas, i.e. the monoclonally established somatotroph adenomas develop further under the influence of locally produced GHRH. The demonstration of GHRH production by this somatotroph adenoma is of importance in clarifying the autocrine or paracrine regulation of GH production and the progression of human somatotroph adenomas.- - - - - - - - - - ranking = 2.8028384909606keywords = pituitary, pituitary gland, gland (Clic here for more details about this article) |
17/303. danazol and multiple hepatic adenomas: peculiar clinical findings in an acromegalic patient.Hepatic adenomas are rare tumors; they have been associated with the use of anabolic steroids. acromegaly increases the overall risk of neoplasms. We report the case of a female acromegalic patient in whom multiple hepatic adenomas appeared soon after danazol treatment for uterine fibromatosis. Treatment of acromegaly with octreotide, followed by successful selective pituitary adenomectomy, stabilized the number and the size of the liver tumors. We suggest that oversecretions of GH and IGF-I were strong promoting factors for liver tumorigenesis in this patient.- - - - - - - - - - ranking = 0.90141924548029keywords = pituitary (Clic here for more details about this article) |
18/303. Regression of acromegaly following pituitary apoplexy.A case of acromegaly complicated by pituitary apoplexy is described. The pituitary apoplexy occurred while the patient was under investigation in a metabolic ward permitting full assessment of pituitary function both before and immediately after the event. This demonstrated a remarkably selective reduction in the plasma growth hormone concentration with preservation of other pituitary function excluding mild diabetes insipidus. The plasma growth hormone fell from values greater than 120 ng/ml to less than 4 ng/ml. The brisk inappropriate release of growth hormone observed on stimulation with thyrotrophic hormone releasing hormone, associated with a severe headache and the onset of pituitary apoplexy two days later raised the possibility of provocative tests of pituitary function precipitating pituitary apoplexy.- - - - - - - - - - ranking = 9.9156117002832keywords = pituitary (Clic here for more details about this article) |
19/303. pituitary apoplexy probably due to TRH and GnRH stimulation tests in a patient with acromegaly.pituitary apoplexy is the most serious and life-threatening complication of pituitary adenomas. Most of the cases occur spontaneously but it may occur also after a number of events such as the pituitary stimulation tests. We report a case of acromegaly due to a giant pituitary adenoma in which pituitary apoplexy developed 88 hours after TRH/GnRH stimulation test. The patient had severe headaches, nausea, vomiting, visual disturbance and mental alteration and the computed tomography (CT) scans revealed intratumoral and intraventricular bleeding. The pituitary mass was removed by transsphenoidal approach. The patient developed pneumonia and died on the 9th postoperative day. pituitary apoplexy was confirmed at surgery and on histological examination. Immunohistochemical staining was positive for GH and PRL. This case indicates that pituitary apoplexy may develop several days after TRH/GnRH stimulation test.- - - - - - - - - - ranking = 5.4085154728817keywords = pituitary (Clic here for more details about this article) |
20/303. acromegaly with normal growth-hormone levels and pituitary histology. Case report.In rare cases, acromegalic patients have normal basal concentrations of growth hormone, and their acromegaly results from abnormal growth-hormone secretory patterns. A patient is reported with the clinical features of acromegaly, who had elevated somatomedin levels and an enlarged sella turcica, but whose serum growth-hormone levels on continuous monitoring were in the normal range, with levels of 2.8 to 8.9 ng/ml. Dynamic studies of growth hormone revealed normal responses to hypo- and hyperglycemia, but abnormal responses to L-dopa and thyroid-releasing hormone. At surgery, neither a pituitary adenoma nor eosinophilic hyperplasia was present. It is likely that this patient's acromegaly resulted from the presence of chronically high normal levels of growth hormone.- - - - - - - - - - ranking = 4.5070962274014keywords = pituitary (Clic here for more details about this article) |
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