Tumors pituitary

Braughler, J.M., Chase, R.L., NefF, G.L., Yonkers, P.A., Day, J.S., HaU, E.D., Sethy, V.H. and Lahti, R.A. (1988). A new 21-amino steroid antioxidant lacking glucocorticoid activity stimulates ACTH secretion and blocks arachidonic acid release from mouse pituitary tumor (ArT-20) cells. J. Pharmacol. Exp. Ther, 244, 423-427. 

Secondary hyperthyroidism TSH-secreting pituitary tumors Trophoblastic (hCG-secreting) tumors Gestational thyrotoxicosis... 

ACTH-secreting pituitary tumor (Cushing s disease)—70% of cases of endogenous Cushing s syndrome... 

ACTH-secreting non-pituitary tumors (ectopic ACTH syndrome)—15% of cases of endogenous Cushing s syndrome usually from small cell lung carcinoma, bronchial carcinoids, pheochromocytoma, or thymus, pancreatic, ovarian, or thyroid tumor. The tumor is usually disseminated (difficult to localize). 

CRH-secreting non-pituitary tumors (ectopic CRH syndrome)— rare... 

O Surgical resection of the pituitary tumor through transsphenoidal pituitary microsurgery is the treatment of choice for most patients with growth hormone-producing pituitary adenomas. 

Without obvious pituitary tumor but proven acromegaly, measurement of GHRH may be helpful to detect ectopic tumors. 

MRI and CT scan Both reveal a pituitary tumor approximately 5 mm in diameter. 

Since up to 10% of pituitary tumors may recur within 15 years following surgery,6,14 continual postoperative monitoring is recommended. 

Review the available diagnostic data to determine pituitary tumor size and location. Determine if the patient has a coexisting prolactin-secreting tumor. Determine if the tumor extends toward the optic chiasm or if it is continuous on the optic tracts. 

Ovarian polycystic ovarian syndrome Pituitary tumors ... 

Increased body weight may be associated with prolactin-secreting pituitary tumor. 

Prevent progression of pituitary tumor or hypothalamic disease. 

Nelson s syndrome A condition characterized by the aggressive growth of a pituitary tumor and hyperpigmentation of the skin. Neoadjuvant therapy Therapy given prior to the primary treatment. In cancer, it is usually given prior to surgery to make the surgical... 

NakayamaK, IshidaN, Shirane Metal 1996 Mice lacking p27(Kipl) display increased body size, multiple organ hyperplasia, retinal dysplasia, and pituitary tumors. Cell 85 707-720... 

Nurse P 1990 Universal control mechanism regulating onset of M-phase. Nature 344 503-508 Pei L, Melmed S 1997 Isolation and characterization of a pituitary tumor-transforming gene (.PTTG). Mol Endocrinol 11 433-441... 

Growth inhibited organ/BW ratios increased in brain, liver, spleen, kidney, heart (females), and testes. Mammary and pituitary tumors commonly observed in treated and in control groups. No statistically significant difference in number or type of neoplasms, except for mammary tumors... 

TSH-secreting pituitary tumors release biologically active hormone that is unresponsive to normal feedback control. The tumors may cosecrete... 

Pituitary failure (secondary hypothyroidism) is an uncommon cause resulting from pituitary tumors, surgical therapy, external pituitary radiation, postpartum pituitary necrosis, metastatic tumors, tuberculosis, histiocytosis, and autoimmune mechanisms. 

Norfleet AM, Thomas ML, Gametchu B, Watson CS (1999) Estrogn receptor-a detected on the plasma membrane of aldehyde-fixed GH3/B6FIO rat pituitary tumor cells by enzyme-linked immunocytochemistry. Endocrinology 140 3805-3814... 

GgO- igsp) Pituitary tumors, adenomas, endocrine ovarian tumors... 

Male patients hypophysectomized because of a pituitary tumor, who had normal semen counts despite undetectable serum gonadotropins after surgery, have been discovered to harbor constitutively active forms of the FSHR gene. Because the benign phenotype is only unmasked by the development of an unrelated tumor, the frequency of these mutations in the general population is difficult to evaluate (83,86). 

Octreotide is a somatostatin analogue it is used in the treatment of somatostatin-secreting pituitary tumors. 

Nakayama, K., Ishida, N., Shirane, M., Inomata, A., Inoue, T., Shishido, N., I., H., Loh, D., and Nakayama, K. (1996). Mice lacking p27 display increased body size, multiple organ hyperplasia, retinal dysplasia, and pituitary tumors. Cell 85, 707-720. 

A recent study confirmed that ethylene thiourea was carcinogenic in male and female rats as shown by increased incidences of thyroid follicular cell neoplasms after treatment of up to 250 ppm in the diet for 2 years. In mice, concentrations ranging from 100 to 1000 ppm for 2 years caused liver and pituitary tumors in addition to thyroid tumors. Perinatal exposure up to 8 weeks followed by a control diet for 2 years was not carcinogenic in rats or mice. Combined perinatal-adult ETU exposures produced the same carcinogenic effects as adult-only exposures. 

Carcinogenesis There has been evidence of oncogenic activity in studies with oxytetracycline (adrenal and pituitary tumors) in rats and minocycline (thyroid tumors) in rats and dogs. 

Alvaro V, Levy L, Dubray C, Roche A, Peillon F, Querat B, Joubert D (1993) Invasive human pituitary tumors express a point-mutated alpha-protein kinase C. J Clin Endocrinol Metab 77 1125-1129... 

Bromocriptine (Parl el) [Antiparkinsonian Agent/Dopamine Receptor Agonist] Uses Parkin on Dz, hyperprolactinemia, acromegaly, pituitary tumors Action Direct-acting on the striatal dopamine receptors X prolactin secretion Dose Initial, 1.25 mg PO bid titrate to effect, w/ food Caution [B, ] Contra Severe ischemic heart Dz or PVD Disp Tabs, caps SE X BP, Raynaud phenomenon (vasospastic disorder resulting in discoloration of the fmgers/toes), dizziness, N, hallucinations Interactions T Effects W/ erythromycin, fluvoxamine, nefazodone, sympathomimetics, antihypertensives X effects W/ phenothiazines, antipsychotics EMS Monitor BP may cause intolerance to EtOH OD May cause NA, severe hypotension give IV fluids symptomatic and supportive... 

Secondary hypothyroidism, or pituitary hypothyroidism, is the consequence of impaired thyroid-stimulating hormone (TSH) secretion and is less common than primary hypothyroidism. It may result from any of the causes of hypopituitarism (e.g., pituitary tumor, postpartum pituitary necrosis, trauma). Patients with secondary hypothyroidism exhibit undetectable or inappropriately low serum TSH concentrations. In secondary hypothyroidism, a normal thyroid gland lacks the normal level of TSH stimulation necessary to synthesize and secrete thyroid hormones. Such patients usually also have impaired secretion of TSH in response to exogenous thyrotropin-releasing hormone (TRH) administration. 

Tertiary hypothyroidism, or hypothalamic hypothyroidism, results from impaired TRH stimulation of pituitary TSH. This may be due to a disorder that damages the hypothalamus or interferes with hypothalamic-pituitary portal blood flow, thereby preventing delivery of TRH to the pituitary. Tumors, trauma, radiation therapy, or infiltrative disease of the hypothalamus can cause such damage. This relatively rare form of hypothyroidism is also characterized by inappropriately low levels of serum TSH. 

Drummond AH, Raeburn CA The interaction of lithium with thyrotropin releasing hormone-stimulated lipid metabolism in GH3 pituitary tumor cells. Biochem J 224 129-136, 1984... 

Clifton, K.H. and Crowley, J.J. (1978). Effects of radiation type and dose and the rate of glucocorticoids, gonadectomy, and thyroidectomy in mammary tumor induction in mammotrophic-secreting pituitary tumor-grafted rats, Cancer Res. 38,1507. 

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