title: Thyrotropin-secreting pituitary adenomas: report of seven cases.
abstract: Seven patients with hyperthyroidism due to a TSH-secreting pituitary macroadenoma have been observed of a total of 800 patients with pituitary tumors over a period of 15 yr. Serum TSH levels varied between 1.1-36.3 mU/L. The serum alpha-subunit level was low in 1 case, while in 4 other cases the concentration was elevated and varied between 3.7-7.8 micrograms/L. Serum TSH beta levels were normal in the 4 cases in which it was determined. Serum GH or PRL levels were elevated in 5 cases. In 1 patient the cosecretion of TSH, GH, and PRL was confirmed by immunocytochemical examination. Serum TSH and alpha-subunit responses to TRH, GnRH, CRF, GRF, dexamethasone, methimazole, T3, and bromocriptine administration were variable when studied. Serum TSH and alpha-subunit circadian rhythms were absent in 1 case and inverted in another. A serum alpha-subunit pulsatility without TSH pulses was observed in 1 patient. Five patients underwent transsphenoidal adenomectomy. Three of 4 patients operated on in our center were cured, but a recurrence of the adenoma was found in 1 of them after 5 yr. The fifth patient was not cured. Treatment with octreotide in 3 patients resulted in normalization of serum TSH, GH, and thyroid hormones levels. Cosecretion of PRL in 1 case and alpha-subunit in 2 cases was also inhibited. Partial tachyphylaxis occurred in 1 patient. In summary, heterogeneity in clinical presentation, hormonal expression, and therapeutic response appears to characterize these TSH-secreting adenomas.
authors.affiliation: Department of Endocrinology, University of Liège, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Beckers
authors.forename: R
authors.initials: R
authors.lastname: Abs
authors.forename: C
authors.initials: C
authors.lastname: Mahler
authors.forename: J L
authors.initials: JL
authors.lastname: Vandalem
authors.forename: G
authors.initials: G
authors.lastname: Pirens
authors.forename: G
authors.initials: G
authors.lastname: Hennen
authors.forename: A
authors.initials: A
authors.lastname: Stevenaert
mesh_terms: D000236:Adenoma / Q000150:complications / Q000378:metabolism* / Q000628:therapy; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001971:Bromocriptine; D002940:Circadian Rhythm; D005260:Female; D015292:Glycoprotein Hormones, alpha Subunit / Q000097:blood; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006980:Hyperthyroidism / Q000188:drug therapy / Q000209:etiology; D008297:Male; D008713:Methimazole / Q000627:therapeutic use; D008875:Middle Aged; D015282:Octreotide / Q000627:therapeutic use; D010911:Pituitary Neoplasms / Q000150:complications / Q000378:metabolism* / Q000628:therapy; D011388:Prolactin / Q000097:blood; D013972:Thyrotropin / Q000097:blood / Q000378:metabolism*; D013973:Thyrotropin-Releasing Hormone
chemical_list: D015292:Glycoprotein Hormones, alpha Subunit; D001971:Bromocriptine; D008713:Methimazole; D013973:Thyrotropin-Releasing Hormone; D011388:Prolactin; D013972:Thyrotropin; D013006:Growth Hormone; D015282:Octreotide