title: Ectopic Cushing's syndrome caused by a pulmonary ACTH-secreting tumor in a patient treated with octreotide.
abstract: Ectopic ACTH syndrome is a rare disease often associated with severe hypercortisolism. When feasible, optimal management is surgical excision of the tumor. A 33-year-old male patient was admitted to the hospital in 1993 with clinical manifestations suggestive of Cushing's syndrome. He presented high plasma ACTH and markedly elevated urinary free cortisol excretion that was not suppressed with high-dose dexamethasone administration. Pituitary MRI scan was normal. No central-to-peripheral ACTH gradient was present in bilateral inferior petrosal sinus sampling. Thoracic CT scan showed a 1.7 cm nodule at the left lung. Pulmonary fine needle cytology and immunocytochemical and ultrastructural studies, together with the presence of bone metastases, led to the diagnosis of an ACTH-producing neuroendocrine carcinoma. He was initially submitted to chemotherapy and has been on treatment with octreotide LAR since 1998, having shown a favorable clinical, biochemical and imaging response. We highlight the excellent long-term response to medical therapy with octreotide LAR, without tachyphylaxis, probably due to its antiproliferative effect.
authors.affiliation: Department of Endocrinology, Diabetes and Metabolism, Centro Hospitalar de São João EPE, Porto, Portugal. pmm_rodrigues@hotmail.com
authors.forename: Pedro
authors.initials: P
authors.lastname: Rodrigues
authors.forename: José Luís
authors.initials: JL
authors.lastname: Castedo
authors.forename: Margarida
authors.initials: M
authors.lastname: Damasceno
authors.forename: Davide
authors.initials: D
authors.lastname: Carvalho
mesh_terms: D000182:ACTH Syndrome, Ectopic / Q000150:complications* / Q000188:drug therapy; D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D018278:Carcinoma, Neuroendocrine / Q000150:complications* / Q000188:drug therapy / Q000378:metabolism; D003480:Cushing Syndrome / Q000209:etiology*; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications* / Q000188:drug therapy / Q000378:metabolism; D008297:Male; D015282:Octreotide / Q000627:therapeutic use*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D015282:Octreotide