title: Treatment of thyrotropin-secreting pituitary adenomas with octreotide.
abstract: Five hyperthyroid patients with TSH-secreting pituitary adenoma were treated with octreotide. Acute administration of octreotide decreased plasma TSH levels in all patients (mean decrease, 50.6 +/- 14%). Treatment with octreotide (25-300 microg/day) for 2-360 weeks resulted in reductions in plasma TSH and alpha-subunit levels in three patients, and serum free thyroxine levels were normalized with concomitant clinical improvements such as disappearance of excessive sweating, tachycardia and finger tremors. In two patients, plasma TSH and free thyroxine levels were initially decreased, but tachyphylaxis occurred 3 and 10 weeks after the initiation of therapy. Mild to marked shrinkage of the tumor was observed 2-50 weeks later in four patients. Shrinkage of the tumor seems to be reversible in one case. Frequent bowel movements and epigastric discomfort occurred in two patient. Somatostatin receptor subtype 2 (sst2) mRNAs were detected in two adenoma tissues studied by RT-PCR. Long-term treatment with octreotide is effective in controlling hyperthyroidism and tumor growth in patients with TSH-secreting pituitary adenoma.
authors.affiliation: Department of Laboratory Medicine, Kyoto University Graduate School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Shimatsu
authors.forename: H
authors.initials: H
authors.lastname: Murabe
authors.forename: K
authors.initials: K
authors.lastname: Kamoi
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Nakao
mesh_terms: D000236:Adenoma / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D015292:Glycoprotein Hormones, alpha Subunit / Q000097:blood; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000008:administration & dosage / Q000627:therapeutic use*; D010911:Pituitary Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis; D017481:Receptors, Somatostatin / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013972:Thyrotropin / Q000378:metabolism*; D013973:Thyrotropin-Releasing Hormone; D013974:Thyroxine / Q000097:blood; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D015292:Glycoprotein Hormones, alpha Subunit; D012333:RNA, Messenger; D017481:Receptors, Somatostatin; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin; D013974:Thyroxine; D015282:Octreotide