Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An immunocytochemical study was performed by the indirect peroxidase method on the pituitary tumour of 37 patients with clinical and biological signs of silent adenoma. Antisera were used against human PRL, human GH, ACTH1-24, human ACTH17-39, alpha-melanocyte stimulating hormone (alpha-MSH), human beta-endorphin, alpha-subunit of hCG (hCG-alpha), and beta-subunits of human LH (LH-beta), human FSH (FSH-beta) and human TSH (TSH-beta). Immunostaining in at least 5% of the tumour cell population, with one or more antisera, was present in 13 cases; hCG-alpha immunostaining was the one most frequently observed. Combined immunostaining was found in 7 cases. Exclusive immunostaining was present in 6 cases: 4 with hCG-alpha, 1 with ACTH1-24 and 1 with TSH-beta. It is concluded that a significant number of silent pituitary adenomas show a certain secretory pattern of pituitary hormones or subunits of glycoprotein hormones as revealed by the immunocytochemistry.
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PMID:The immunocytochemical heterogeneity of silent pituitary adenomas. 284 Jul 93

The frequency of gonadotroph cell adenomas among all unselected pituitary adenomas is likely much higher than previously suspected. The prevalence in one series of 139 men with pituitary macroadenomas was 17 per cent (24 per cent if adenomas secreting only alpha subunit are included). The clinical characteristics of patients with gonadotroph cell adenomas are similar. Most are middle-aged men who have a history of normal pubertal development and a normal fertility history and by examination are normally virilized and have testes of normal size. They are brought to medical attention because of visual impairment, which is the result of the enormous size of the adenoma. The most common hormonal characteristics of gonadotroph cell adenomas in vivo is hypersecretion of FSH, which is often accompanied by hypersecretion of FSH-beta and alpha subunits and less often by hypersecretion of LH-beta or intact LH. Another common characteristic is secretion of FSH and/or LH-beta in response to TRH. A few patients with gonadotroph cell adenomas hypersecrete intact LH and therefore have supranormal serum testosterone concentrations. A larger number have secondary hypogonadism, because the adenomas are not secreting intact LH but are compressing the normal gonadotroph cells and impairing LH secretion. These patients have concentrations of intact LH that are not elevated, despite subnormal testosterone concentrations. The testosterone increases markedly in response to human chorionic gonadotropin. Both the clinical and hormonal characteristics of gonadotroph cell adenomas usually make them readily distinguishable from pituitary enlargement due to long-standing primary hypogonadism. Most gonadotroph cell adenomas are now managed first by transsphenoidal surgery to attempt to restore vision as quickly as possible, and then by supervoltage radiation to prevent regrowth of the remaining adenomatous tissue. Surgery usually does improve vision, as well as the pretreatment hormonal abnormalities, and radiation reduces FSH hypersecretion further. Dopamine agonist therapy is experimental but warrants further trial. The hormonal abnormalities detected prior to treatment, such as supranormal basal concentrations of FSH, alpha, and FSH-beta and the FSH and LH-beta responses to TRH, can be used to monitor the response to therapy.
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PMID:Gonadotroph cell pituitary adenomas. 331 1

Nonfunctioning pituitary adenomas represent approximately 25 per cent of all clinically apparent pituitary tumors. The tumors are usually macroadenomas and present with symptoms caused by mass effect or hypopituitarism. In addition to structural studies and assessment of pituitary hormone function, all patients with clinically nonfunctioning tumors should have an alpha-subunit determination. High normal or elevated gonadotropins in this setting are suspicious for an underlying gonadotroph adenoma. Alpha subunit, LH-beta, and FSH-beta can be measured in the serum of some patients with nonfunctioning adenomas. Other groups of patients may have tumors in which defects in hormone biosynthesis or processing prevent detectable hormone hypersecretion, or no hormones are produced. The majority of nonfunctioning adenomas have evidence of gonadotropin or glycoprotein hormone subunit production when studied in vitro. An additional tumor group has evidence of ACTH production without biochemical hypercortisolism. Transsphenoidal decompression is the treatment of choice for patients with nonfunctioning adenomas. Pituitary function may improve following surgery in a subset of patients. Postoperative conventional radiotherapy is recommended when there is evidence of residual tumor and/or extensive extrasellar extension preoperatively.
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PMID:Nonsecreting pituitary tumors. 331 3

Two of 420 patients with pituitary adenoma who underwent operation from 1989 to 1997 had thyroid stimulating hormone (TSH) producing adenoma. We investigated these TSH cell adenomas with immunohistochemical and ultrastructural methods and compared their ultrastructural features with brefeldin A (BFA, 0.5 mg/ml) treated pituitary adenoma cells. BFA-treated pituitary adenomas include a prolactin (PRL) cell adenoma, a growth hormone (GH) cell adenoma, an adrenocorticotropic hormone (ACTH) cell adenoma, a gonadotroph adenoma, and a plurihormonal adenoma. Immunohistochemical staining disclosed that one of the TSH cell adenomas produced only TSH-beta and that another produces both TSH-beta and FSH-beta. Ultrastructural analysis showed the abundance of oval-shaped dilated rough endoplasmic reticulum (rER). Within the dilated rER, the mistlike deposit or deposit along the inner margin of the rER membrane was observed. On the other hand, BFA-treated cultured pituitary adenoma cells showed the opening of the cavity of the rER cisterna and they enlarged to an oval form with time and revealed an accumulation of electron-dense deposits within the dilated rER. These ultrastructural similarities between TSH cell adenoma and BFA-treated pituitary adenoma cells indicate the functional disturbances in the secretory passage through the Golgi apparatus in TSH cell adenoma cells.
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PMID:Ultrastructural characteristics of TSH-producing adenomas with special reference to its close similarity to BFA-treated pituitary adenoma cells. 1108 Dec 1

Female gonadotroph adenomas with endocrinological symptoms are uncommon. Six cases of such adenomas have been reported in the literature: two were girls who presented with precocious puberty and four were premenopausal women with accompanying multiple ovarian cysts. We describe here a 10-year-old Japanese girl with a gonadotroph macroadenoma and present detailed morphological findings of the tumor. The patient's chief complaints were nausea, abdominal distention, and abdominal pain. Abdominopelvic ultrasonography and magnetic resonance imaging (MRI) revealed bilateral multiple ovarian cysts. Endocrinological assays showed elevated serum follicle-stimulating hormone (FSH) (33.7 mIU/ml) and estradiol (3840 pg/ml). MRI of the head showed a large pituitary tumor. Two transsphenoidal operations and subsequent radiation therapy were performed. Immunohistochemically, more than half the tumor cells were positive for anti-FSH-beta monoclonal antibody. Ultrastructurally, the tumor cells exhibited a fairly uniform picture of rounded cells. Their nuclei were slightly irregular and contained heterochromatin, and their cytoplasm contained many round, dense core granules, measuring 140-260 nm in diameter, together with well-developed organelles. An in vitro study showed that the tumor cells in primary culture produced FSH (1089.0 mIU/ml). To our knowledge, this is the first immunohistochemical and ultrastructural study of an FSH-secreting gonadotroph adenoma occurring in childhood.
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PMID:An immunohistochemical and ultrastructural study of a follicle-stimulating hormone-secreting gonadotroph adenoma occurring in a 10-year-old girl. 1181 Apr 54

Gonadotropin-producing pituitary adenomas are extremely rare in reproductive-age women. We report here a case of gonadotroph microadenoma with ovarian hyperstimulation. It was found in a 29-yr-old infertile Japanese woman with enlarged multicystic ovaries. The patient had an elevated basal serum estradiol level (up to 6755 pM, or 1840 pg/ml). Serum FSH and prolactin were mildly elevated (15.4 IU/liter, 1.4 nM or 31.4 ng/ml), whereas LH was low (0.5 IU/liter). The FSH level was paradoxically elevated in response to TRH administration. Dynamic magnetic resonance imaging revealed a pituitary microadenoma. Daily administration of bromocriptine, a dopamine agonist, normalized the ovarian size, and the patient ovulated naturally. She conceived after 3 months of bromocriptine therapy and delivered a normal child. She underwent elective transsphenoidal pituitary surgery, 3 yr after the delivery. Immunostaining of the resected tumor showed that 80% and less than 5% of the tumor cells stained for FSH-beta and prolactin, respectively. Furthermore, RT-PCR suggested that dopamine type 2 receptor was expressed in the adenoma. Gonadotroph microadenoma should be considered in women with spontaneous ovarian hyperstimulation, even if they have no neurological symptoms or marked pituitary enlargement. In such cases, bromocriptine therapy may be an alternative to pituitary surgery.
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PMID:Successful pregnancy after bromocriptine therapy in an anovulatory woman complicated with ovarian hyperstimulation caused by follicle-stimulating hormone-producing plurihormonal pituitary microadenoma. 1272 42