title: Papillary thyroid carcinoma metastatic to the pituitary gland.
abstract: Many malignancies may present with metastases to the pituitary gland. The association of thyroid carcinoma with pituitary metastases is, however, very rare. This report describes two patients in whom metastases from a papillary thyroid carcinoma to the pituitary gland resulted in panhypopituitarism with blunted endogenous thyrotropin (TSH) production following withdrawal of levothyroxine. Both required the use of recombinant human TSH prior to radioiodine therapy. Symptoms of hypopituitarism may be difficult to distinguish clinically from those of hypothyroidism in the setting of levothyroxine withdrawal. Clinicians should be aware of the clinical and biochemical manifestations of this rare association.
authors.affiliation: Department of Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8020, USA.
authors.forename: U S
authors.initials: US
authors.lastname: Masiukiewicz
authors.forename: I A
authors.initials: IA
authors.lastname: Nakchbandi
authors.forename: A F
authors.initials: AF
authors.lastname: Stewart
authors.forename: S E
authors.initials: SE
authors.lastname: Inzucchi
mesh_terms: D002291:Carcinoma, Papillary / Q000473:pathology / Q000556:secondary* / Q000628:therapy; D005260:Female; D006801:Humans; D007018:Hypopituitarism / Q000209:etiology; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000150:complications / Q000556:secondary*; D011994:Recombinant Proteins / Q000627:therapeutic use; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000628:therapy; D013972:Thyrotropin / Q000096:biosynthesis / Q000627:therapeutic use; D013974:Thyroxine / Q000008:administration & dosage
chemical_list: D007457:Iodine Radioisotopes; D011994:Recombinant Proteins; D013972:Thyrotropin; D013974:Thyroxine