title: Ectopic ACTH-secreting syndrome: a single-center experience.
abstract: OBJECTIVE
  Ectopic adrenocorticotropic hormone (ACTH)-secreting syndrome (EAS) is a rare cause of ACTH-dependent endogenous hypercortisolism. The objective of this study was to analyze clinical, biochemical, and imaging characteristics; management strategies; and outcomes of EAS patients.
  
  
  METHODS
  We screened the records (1993-2012) of ACTH-dependent endogenous hypercortisolism cases managed at a tertiary care center.
  
  
  RESULTS
  Of the 218 patients, 17 were diagnosed with EAS. The median 8:00 AM serum cortisol was 36 μg/dL (11.4-82.7 μg/dL), and the median basal plasma ACTH was 156 pg/mL (53.5-468 pg/mL). Notably, ACTH levels below 100 pg/mL were found in 4 patients. Suspicious microadenoma was found on magnetic resonance imaging (MRI) of the pituitary in 5 patients, and all of them underwent transsphenoidal surgery (TSS). Inferior petrosal sinus sampling (IPSS) was performed in 8 patients, and the results were suggestive of a peripheral source in all 8. Computed tomography (CT) localized the lesion in 15/17 patients. In 2 patients with negative CTs, gallium DOTATATE positron emission tomography (PET) scans localized the lesion. Despite difficulties localizing bronchial carcinoids, the cure rate was high (72%). In contrast, thymic carcinoids were easily localized but had poor outcomes.
  
  
  CONCLUSIONS
  EAS cannot be ruled out on the basis of marginally elevated ACTH. In cases with an equivocal MRI pituitary finding, prior IPSS can help avoid unnecessary TSS. CT is a useful modality for localization of an ectopic source. Functional imaging may help in cases where anatomical imaging fails.
authors.affiliation: Department of Endocrinology, Seth G S Medical College, KEM Hospital, Mumbai, India.
authors.forename: Harshal R
authors.initials: HR
authors.lastname: Kakade
authors.forename: Rajeev
authors.initials: R
authors.lastname: Kasaliwal
authors.forename: Varsha S
authors.initials: VS
authors.lastname: Jagtap
authors.forename: Amol
authors.initials: A
authors.lastname: Bukan
authors.forename: Sweta R
authors.initials: SR
authors.lastname: Budyal
authors.forename: Shruti
authors.initials: S
authors.lastname: Khare
authors.forename: Anurag R
authors.initials: AR
authors.lastname: Lila
authors.forename: Tushar
authors.initials: T
authors.lastname: Bandgar
authors.forename: Padmavathy S
authors.initials: PS
authors.lastname: Menon
authors.forename: Nalini S
authors.initials: NS
authors.lastname: Shah
mesh_terms: D000182:ACTH Syndrome, Ectopic / Q000175:diagnosis / Q000473:pathology / Q000628:therapy*; D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D015415:Biomarkers / Q000097:blood; D001984:Bronchial Neoplasms / Q000150:complications / Q000473:pathology / Q000628:therapy; D002648:Child; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism; D003480:Cushing Syndrome / Q000097:blood / Q000209:etiology; D005260:Female; D005708:Gallium; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000150:complications / Q000473:pathology / Q000628:therapy; D010902:Pituitary Gland / Q000473:pathology; D012189:Retrospective Studies; D013953:Thymus Neoplasms / Q000150:complications / Q000473:pathology / Q000628:therapy; D013964:Thyroid Neoplasms / Q000150:complications / Q000473:pathology / Q000628:therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015415:Biomarkers; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D005708:Gallium; D006854:Hydrocortisone