1/843. acromegaly in a family without a mutation in the menin gene.Familial pituitary tumors are rare. Only 45 cases in 20 families with acromegaly have been reported. A third of the cases (30%) is related to multiple endocrine neoplasia type 1 (MEN 1). We report two cases of acromegaly in one family with pituitary macroadenomas. A 46-year-old woman with elevated serum growth hormone (GH) and insulin-like growth factor (IGF-1) and a failure to supress GH in the glucose tolerance test underwent transsphenoidal surgery 4 years ago. Three years later her 24-year-old son also presented with typical signs of acromegaly. A pituitary macroadenoma was identified by MRT and he also underwent transsphenoidal surgery. There were no symptoms of McCune-Albright syndrome or other forms of endocrine hyperfunction in the two patients. In an attempt to identify the molecular etiology of the tumours dna was extracted from paraffin fixed tissue from both patients. Exon 7 to 13 of the Gsp-protein and exons 1 to 10 of the menin gene were amplified by PCR. Although Gsp mutations have been identified in 40% of somatotroph tumors, direct sequencing of the PCR products showed no mutations in exons 7 to 13 of Gs alpha. Moreover no mutations were found in exons 1 to 10 of the menin gene. Therefore, molecular causes other than Gsp or menin gene mutations have to be considered as the molecular etiology of acromegaly in this family.- - - - - - - - - - ranking = 1keywords = hormone (Clic here for more details about this article) |
2/843. Intrasellar malignant lymphoma developing within pituitary adenoma.A mixed lymphoblastic T cell lymphoma and gonadotroph cell pituitary adenoma occurred 25 years after first resection of the adenoma. Within 1 year the lymphoma overgrew the adenoma, but was still restricted to the sellar region. Histologically, lymphoma and adenoma components were tightly admixed. Possible pathogenetic pathways for intra-adenomatous lymphoma development include monoclonal expansion of T cell infiltrates, expression of adhesion molecules specific for adenoma endothelium, and production of mitogenic pituitary hormones.- - - - - - - - - - ranking = 1keywords = hormone (Clic here for more details about this article) |
3/843. acromegaly: report of two patients with an unusual presentation.The presenting features of functionally active pituitary tumours depend on the specific hormone which is overproduced. growth hormone (GH) producing tumours usually present with the clinical manifestations of acromegaly due to excessive GH secretion or symptoms resulting from mass effects of the enlarging tumour. The changes in physical features and the increase in tumour size are usually insidiously slow and therefore, recognition of the disease is delayed. In this report two patients with acromegaly are described with an atypical presentation due to acute onset of symptoms. The first patient presented with central diabetes insipidus. The diagnosis acromegaly was made on physical examination. The second patient presented with a generalized seizure during sleep. On CT-scanning a large tumour protruding into the left temporal lobe connected to the pituitary gland was seen. immunohistochemistry of the tumour after partial transcranial resection confirmed the clinical diagnosis of acromegaly. At a later stage transsphenoidal resection of the pituitary tumour was performed with full recovery and without loss of pituitary function.- - - - - - - - - - ranking = 3.8019059799478keywords = secretion, hormone (Clic here for more details about this article) |
4/843. Unusual MRI finding of multiple adenomas in the pituitary gland: a case report and review of the literature.The simultaneous occurrence of multiple adenomas in the pituitary gland is a rare event. We report the coexistence of three non functioning pituitary microadenomas in a 37-year-old woman, referred to us for oligomenorrhea and headache. Biochemical evaluation revealed prolactin (131 U/liters), follicle-stimulating hormone (4.1 U/liters), luteinizing hormone (3.9 U/liters), 17beta-estradiol (74 pg/mL), free (2.0 pg/mL) and total testosterone (0.5 ng/mL), dehydroepiandrosterone-sulfate (3.5 microg/mL), 17OH-progesterone (0.8 ng/mL), cortisol (13.1 microg/dL), free triiodothyronine (4.8 pmol/L), free thyroxine (18.5 pmol/liters), thyrotropin (1.6 mU/L), and growth hormone (0.2 ng/mL) levels in the normal range, as for as the response to dynamic endocrine tests. MRI showed an enlarged sella turcica, occupied by three distinct hypointense areas that measured less than 5 mm in diameter in the left, medium and right side of the pituitary, respectively. This finding was confirmed 6 months later by a second MRI that revealed also a light increase in microadenomas dimensions. The patient, therefore, underwent neurosurgery by transfenoidal approach. Histologic examination showed no morphologic differences between the specimens obtained from the different microadenomas. immunohistochemistry evaluation revealed a positive staining for the common alpha-subunit of glycoproteic hormones and negative for the other pituitary hormones tested, while electron microscopy showed cells with a poor secretory apparatus and a variable grade of cell differentiation. In conclusion, we report the fifth case described with multiple pituitary adenomas diagnosed in vivo and the first with three coexisting tumors revealed by MRI before neurosurgery. The occurrence of multiple pituitary tumors emphasizes the role of pituitary and extrahypophiseal factors in the clonal expansion of genetically altered cells.- - - - - - - - - - ranking = 5keywords = hormone (Clic here for more details about this article) |
5/843. Primary hypothyroidism and pituitary insufficiency.A 40-year-old man with primary hypothyroidism and sellar enlargement is described. There was deficiency of all pituitary tropic hormones except TSH which was elevated. TRH stimulation revealed responsiveness of pituitary thyrotropic cells, and thyroxine administration suppressed the elevated TSH. These findings are compatible with either a TSH-producing chromophobe adenoma resulting from primary hypothyroidism or, because of the suppressibility of the TSH secretion, thyrotropic hyperplasia secondary to hypothyroidism maintaining TSH secretion in the face of a non-TSH-secreting pituitary tumor.- - - - - - - - - - ranking = 4.6038119598956keywords = secretion, hormone (Clic here for more details about this article) |
6/843. Reduction of plasma gonadotropin levels and pituitary tumor size by treatment with bromocriptine in a patient with gonadotropinoma.A pituitary tumor with suprasellar extension was found by magnetic resonance imaging (MRI) in a male with diabetes mellitus. Endocrine examination revealed high plasma follicle-stimulating hormone (FSH) and alpha-subunit levels, which increased with administration of thyrotropin (TSH)-releasing hormone (TRH). plasma luteinizing hormone (LH) and testosterone levels were low. Pituitary gonadotropin producing tumor was diagnosed. Because the patient refused surgery, bromocriptine was administered and plasma FSH and alpha-subunit rapidly decreased; on MRI the tumor size was gradually reduced. When pituitary operation is not feasible, bromocriptine is one choice of treatment.- - - - - - - - - - ranking = 3keywords = hormone (Clic here for more details about this article) |
7/843. Shrinkage of a PRL-secreting pituitary macroadenoma resistant to cabergoline.Cabergoline decreases both serum PRL levels and size of prolactinomas, including some tumors resistant to other dopamine-agonists. It is common observation that the shrinkage of the adenoma is preceded by suppression of PRL levels. A minority of patients, who do not show a significant decrease of PRL after a short trial with dopamine-agonists, undergoes neurosurgery or radiotherapy. We report on the case of a 14-year-old girl with a huge prolactinoma who showed, during cabergoline treatment (0.5 mg twice a week), a significant shrinkage of the pituitary mass but no decrease of the very high PRL values. She was referred to us after partial removal of the suprasellar extension of the pituitary tumor. The post-surgical evaluation showed very high PRL levels (9352 microg/l; 20941 microg/l before surgery), which did not decrease during the 2-year treatment with cabergoline (nadir value: 8735 microg/l). However, one month after the beginning of therapy, MRI showed a significant shrinkage of the tumor (tumor volume 5.7 ml, compared with 45.1 ml prior to surgery and 24.4 ml after surgery). Subsequently MRIs demonstrated a progressive reduction of the size with a complete disappearance of the suprasellar and parasellar tissue (tumor volume 1.8, 0.9 and 0.2 ml, at 3, 6 and 12 months, respectively). The MRI performed at the 24th month showed a secondary empty sella, with residual tumor tissue in the right sphenoidal sinus. Increasing cabergoline, up to 3 mg a week, failed to induce any decrease of PRL levels. In conclusion, in such macroprolactinomas the shrinkage of tumor is not strictly correlated with (or it is partially dissociated from) the inhibition of PRL hypersecretion. The choice of other therapeutic options in cabergoline-resistant macroprolactinomas needs careful neuroradiological evaluation after a short trial of pharmacological treatment.- - - - - - - - - - ranking = 1.8019059799478keywords = secretion (Clic here for more details about this article) |
8/843. Clinical and morphological features of undifferentiated monomorphous GH/TSH-secreting pituitary adenoma.A 41-year-old male presented with progressive visual defects, acromegaly and hyperthyroidism. After clinical evaluation a giant GH/TSH-secreting pituitary adenoma was diagnosed. Administration of the somatostatin analog octreotide at doses of 150 microg s.c. per day inhibited the secretion of both GH and TSH. A three-week treatment with octreotide prior to surgery led to slight visual improvement and CT scan showed some new necrotic areas within the tumor mass. Transcranial surgery was performed. By immunohistochemical analyses of the adenoma tissue GH, prolactin and beta-chorionic gonadotropin were detected; TSH was negative. Electron microscopy revealed an undifferentiated, monomorphous adenoma with morphological features of an acidophil stem cell adenoma such as the presence of misplaced exocytoses, fibrous bodies and mitochondrial gigantism. However, the tumor cells contained small secretory granules (up to 250 nm) accumulated along the cell membrane characteristic of thyrotrope cells. Furthermore, some adenoma cells were fusiform with long cytoplasmic processes resembling thyrotropes. Two months after the operation CT scan revealed a large residual tumor. serum GH and TSH levels had increased again and the TSH level was even higher than before the treatment. The patient died suddenly, most probably of lethal arrhythmia. Specimens of the adenoma tissue obtained at autopsy confirmed the previous findings with the exception of positive immunostaining for TSH which was found in less than 1% of the adenoma cells. This undifferentiated, monomorphous GH/TSH-secreting pituitary adenoma represents an entity that is unusual both in its ultrastructural features and clinical manifestations suggesting a cytogenesis from an early, undifferentiated stem cell.- - - - - - - - - - ranking = 1.8019059799478keywords = secretion (Clic here for more details about this article) |
9/843. Secondary infertility as early symptom in a man with multiple endocrine neoplasia-type 1.Multiple endocrine neoplasia-type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by parathyroid hyperplasia, pancreatic endocrine tumours and pituitary adenomas. Here, we report a patient with a history of insulinoma who developed secondary infertility as a further symptom of the disease. When he was first examined at the age of 36 years, he complained of weakness, reduced libido and impotence. Laboratory evaluation revealed non-obstructive azoospermia and hyperprolactinaemia. In contrast to sexual activity and serum prolactin, semen quality did not significantly respond to bromocriptine therapy. During follow-up, a growing pituitary adenoma caused acromegaly with elevated serum concentrations of growth hormone, insulin-like growth factor 1 (IGF-1), and prolactin. After microsurgery of the tumour at the age of 44 years, sperm concentration persistently increased up to 5.6 x 10(6)/ml. In accordance with the clinical diagnosis of MEN1, dna sequencing revealed a mutation in exon 2 of the menin gene which results in a truncated, inactive protein product. In conclusion, MEN1 with pituitary lesions may cause severe hypogonadism and infertility. Both hyperprolactinaemia and overproduction of growth hormone and IGF-1 seem to be involved in testicular dysfunction in the present case. The possible role of menin in the testis, however, remains to be elucidated.- - - - - - - - - - ranking = 2keywords = hormone (Clic here for more details about this article) |
10/843. growth hormone isoforms in a girl with gigantism.Several previous investigations have suggested that there may be different growth hormone isoforms in patients with acromegaly. We used three different site-specific monoclonal antibodies (MAbs) to investigate growth hormone (GH) isoforms in serum from an 8 year-old girl with a GH and prolactin secreting adenoma. The pattern of GH-immunoreactivity was dependent on the circumstances of collection. serum obtained after oral glucose had very little cross reactivity with MAb 352 although concentrations of up to 15 micrograms/l were found with two other MAbs, 033 and 665. MAb 352 does not recognize the 20,000 dalton isoform of GH (20K) while both MAb 033 and 665 do. The same pattern of GH immunoreactivity (low MAb 352, equal and higher MAb 033 and 665) was seen in other baseline samples. In contrast, samples obtained after TRH/GnRH showed immunoreactivity patterns expected for a mixture of 22,000 dalton isoform of GH (22K) with only a small amount of 20K. GH samples obtained during sleep showed both patterns with episodic peaks with equal immunoreactivity superimposed on the basal pattern (decreased activity with MAb 352). Affinity chromatography of basal samples showed that a portion of the GH immunoreactivity was neither 22K nor 20K, although in stimulated samples, over 70% of GH was 22K or 20K GH. In conclusion, the nature of GH isoforms present in serum varies with GH concentration. These differences may contribute to the known difficulty in correlating disease activity and random GH measurements in patients with GH secreting adenomas.- - - - - - - - - - ranking = 6keywords = hormone (Clic here for more details about this article) |
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