title: Primary Medical Treatment of Thyrotropin-Secreting Pituitary Adenomas by First-Generation Somatostatin Analogs: A Case Study of Seven Patients.
abstract: BACKGROUND
  The first-choice treatment of thyrotropin (TSH)-secreting pituitary adenomas is surgical adenomectomy, with 40-60% of patients cured after surgery. The presence of somatostatin receptors on the adenomatous cells suggests that first-generation somatostatin analogs (octreotide, lanreotide) could be used as an adjuvant treatment to surgery for TSH-secreting pituitary adenomas. The aim of this study is to describe the efficacy and safety of primary medical treatment with first-generation somatostatin analogs in patients with a TSH-secreting pituitary adenoma.
  
  
  METHODS
  Retrospective study on 7 patients (5 women, 2 men) aged 57±14 years with pure TSH (n=4) or mixed TSH/GH (n=3) secreting pituitary adenomas primarily treated with first generation somatostatin analogs. Magnetic resonance imaging revealed a microadenoma in 3 patients and a macroadenoma in 4 patients. The follow-up period was 8.5±7.3 years.
  
  
  RESULTS
  At initial diagnosis, the patients presented with thyrotoxicosis with elevated free thyroxine (26.5±6.5 pg/mL) and free triiodothyronine (7.3±0.9 pg/mL) levels and a mean TSH of 4.3±1.4 mU/L. During somatostatin analog treatment, free thyroid hormones and TSH levels normalized after 4.4±3.9 and 7.0±8.4 months, respectively. At the time of the last visit, 6 patients were biochemically controlled. Adenoma volume decreased in 6 patients and a decrease in adenoma volume persisted in 2 patients several years after initiation of somatostatin analog treatment. Safety of treatment was good and no patients discontinued somatostatin analogs due to side effects.
  
  
  CONCLUSIONS
  This study confirms the efficacy of primary medical treatment with first-generation somatostatin analogs in terms of hormonal control and tumor volume reduction in patients with TSH-secreting pituitary adenomas, and its good safety profile. First-generation somatostatin analogs may serve as a medical alternative to surgical treatment, especially in patients where surgery is contraindicated or in subjects presenting with invasive macroadenomas that render complete surgical resection difficult.
authors.affiliation: 1 Department of Endocrinology and Metabolic Diseases , Larrey Centre Hospitalo-Universitaire, Toulouse, France .
authors.forename: Frédérique
authors.initials: F
authors.lastname: Rimareix
authors.affiliation: 1 Department of Endocrinology and Metabolic Diseases , Larrey Centre Hospitalo-Universitaire, Toulouse, France .
authors.forename: Solange
authors.initials: S
authors.lastname: Grunenwald
authors.affiliation: 1 Department of Endocrinology and Metabolic Diseases , Larrey Centre Hospitalo-Universitaire, Toulouse, France .
authors.forename: Delphine
authors.initials: D
authors.lastname: Vezzosi
authors.affiliation: 2 Department of Neuroradiology , Purpan Centre Hospitalo-Universitaire, Toulouse, France .
authors.forename: Louis-David
authors.initials: LD
authors.lastname: Rivière
authors.affiliation: 1 Department of Endocrinology and Metabolic Diseases , Larrey Centre Hospitalo-Universitaire, Toulouse, France .
authors.forename: Antoine
authors.initials: A
authors.lastname: Bennet
authors.affiliation: 2 Department of Neuroradiology , Purpan Centre Hospitalo-Universitaire, Toulouse, France .
authors.forename: Philippe
authors.initials: P
authors.lastname: Caron
mesh_terms: D000236:Adenoma / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D007273:Injections, Intramuscular; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000627:therapeutic use; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D013004:Somatostatin / Q000031:analogs & derivatives / Q000627:therapeutic use*; D013972:Thyrotropin / Q000378:metabolism*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D013004:Somatostatin; D007334:Insulin-Like Growth Factor I; D013972:Thyrotropin; D013006:Growth Hormone; D013974:Thyroxine; D015282:Octreotide