title: Ectopic ACTH syndrome associated with large cell neuroendocrine carcinoma of the thymus.
abstract: A 38-year-old man was admitted for evaluation of Cushing's syndrome. Physical findings showed swelling of the face, and hypertension, but not Cushingoid stigmata. Laboratory data revealed serum cortisol level of 34.1 µg/dL and plasma ACTH of 140 pg/mL. Overnight administration of 1 and 8 mg dexamethasone did not suppress plasma ACTH or serum cortisol. Chest X-ray showed a mass at the upper-anterior quadrant of the mediastinum, and chest CT scan revealed a heterogenous tumor of approximately 60 mm in diameter, which infiltrated into the superior vena cava and ascending aorta, and caused superior vena cava syndrome. The tumor was resected. Histological examination indicated large cell neuroendocrine carcinoma of the thymus and positive immunoreactivity for ACTH. Ten days after the operation, the plasma ACTH decreased as low as 13.7 pg/mL. The present study indicates that large cell neuroendocrine carcinoma of the thymus can cause superior vena cava syndrome and ectopic ACTH syndrome.
authors.affiliation: Department of Medicine, Jichi Medical University Saitama Medical Center, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Saito
authors.forename: Mizuho
authors.initials: M
authors.lastname: Kimoto
authors.forename: Syuichi
authors.initials: S
authors.lastname: Nakai
authors.forename: Aki
authors.initials: A
authors.lastname: Ikoma
authors.forename: Hideo
authors.initials: H
authors.lastname: Toyoshima
authors.forename: Masanobu
authors.initials: M
authors.lastname: Kawakami
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Nokubi
authors.forename: San-e
authors.initials: SE
authors.lastname: Ishikawa
mesh_terms: D000182:ACTH Syndrome, Ectopic / Q000175:diagnosis*; D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism; D000328:Adult; D018278:Carcinoma, Neuroendocrine / Q000175:diagnosis / Q000378:metabolism* / Q000601:surgery; D003480:Cushing Syndrome / Q000175:diagnosis; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D013953:Thymus Neoplasms / Q000175:diagnosis / Q000378:metabolism* / Q000601:surgery
chemical_list: D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone