[Thyrotropin--TSH secreting pituitary tumor]

Przegl Lek. 2002;59(12):1018-23.
[Article in Polish]

Abstract

Thyrotropin-releasing pituitary tumors represent 0.9 to 2.8% of all pituitary adenomas. They cause secondary or central hyperthyroidism. The diagnosis of these tumors has been increasing in the past 20 years. It was produced by introduction of the sensitive immunoradio-metric assay of TSH and better radiological imaging (magnetic resonance imaging). TSH--secreting pituitary adenomas are aggressive and invasive neoplasms. Most reports describe a poor outcome after pharmacological therapy, surgery and radiation therapy. Presently the diagnosis of thyrotropin-secreting pituitary tumor is based on the lack of: a. inhibition of TSH levels in the presence of increased free thyroid hormones; b. response of TSH to stimulation with TRH; c. and presence of a abnormal, neoplastic(adenomatous) intrasellar or parasellar mass. Surgical excision (selective adenomectomy) by the transsphenoidal route is the first treatment. Craniotomy should be reserved for parasellar tumors with significant lateral extension. Pharmacological pretreatment with long acting somatostatin analogues is recently a standard before surgery. This medical treatment of the TSH-omas is effective in reducing TSH and free thyroid hormone plasma levels. Administration of the somatostatin analogues causing tumor mass shrinkage and changes consistency. This pretreatment is effective therapy and improves surgical outcome especially in patients harbouring macroadenomas. Radiotherapy is noncurative and produces long term complications (hypopituitarism). Authors present and discuss current cure criteria of TSH-omas with reference to their clinical experience.

Publication types

  • Review

MeSH terms

  • Adenoma / diagnosis
  • Adenoma / drug therapy
  • Adenoma / metabolism*
  • Adenoma / radiotherapy
  • Adenoma / surgery
  • Adenoma / therapy*
  • Diagnosis, Differential
  • Hormones / therapeutic use
  • Humans
  • Hyperthyroidism / diagnosis
  • Hyperthyroidism / metabolism
  • Magnetic Resonance Imaging
  • Pituitary Neoplasms / diagnosis
  • Pituitary Neoplasms / drug therapy
  • Pituitary Neoplasms / metabolism*
  • Pituitary Neoplasms / radiotherapy
  • Pituitary Neoplasms / surgery
  • Pituitary Neoplasms / therapy*
  • Somatostatin / therapeutic use
  • Thyrotropin / metabolism*

Substances

  • Hormones
  • Somatostatin
  • Thyrotropin