title: Plasma pro-opiomelanocortin, pro-adrenocorticotropin hormone, and pituitary adenoma size in dogs with Cushing's disease.
abstract: It is difficult to predict the size of pituitary corticotroph tumors in dogs with Cushing's disease (pituitary-dependent hyperadrenocorticism [PDH]) without pituitary imaging techniques. The purpose of this study was to examine the relationship between plasma adrenocorticotropin hormone (ACTH) precursor concentration and pituitary size in dogs with Cushing's disease. Plasma concentrations of ACTH precursors (pro-opiomelanocortin [POMC]/pro-ACTH) and pituitary tumor height/brain area were measured in 36 dogs with pituitary corticotroph adenomas of various sizes. There was a correlation between tumor size (measured as the pituitary tumor height/brain area ratio [P/B]) and POMC/pro-ACTH concentration (r = .70; P < .0001). Dogs with P/B > or = 0.40 x 10(-2) mm(-1) had higher concentrations of ACTH precursors than dogs with P/B < 0.40 x 10(-2) mm(-1) (median concentration 85 pmol/L, range 15-1,350 pmol/L, n = 14 versus 15 pmol/L, range 15-108 pmol/L, n = 22; P < .0001). With a threshold of 35 pmol/L of POMC/pro-ACTH concentration, the estimated sensitivity and specificity of the kit were 93% (95% confidence interval [CI], 79-100%) and 86% (95% CI, 73-100%), respectively. We interpret these data as indicating that measurement of POMC and pro-ACTH might be of value in the characterization of tumor size in dogs with Cushing's disease. Low POMC/pro-ACTH concentrations make it unlikely that a large pituitary tumor exists in dogs with PDH.
authors.affiliation: National Veterinary School of Alfort, Maisons-Alfort, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Granger
authors.forename: Pauline
authors.initials: P
authors.lastname: de Fornel
authors.forename: Patrick
authors.initials: P
authors.lastname: Devauchelle
authors.forename: Sophie
authors.initials: S
authors.lastname: Segond
authors.forename: Françoise
authors.initials: F
authors.lastname: Delisle
authors.forename: Dan
authors.initials: D
authors.lastname: Rosenberg
mesh_terms: D000236:Adenoma / Q000097:blood / Q000473:pathology / Q000662:veterinary*; D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D003348:Cortisone / Q000097:blood; D004283:Dog Diseases / Q000097:blood / Q000473:pathology*; D004285:Dogs; D007124:Immunoenzyme Techniques / Q000662:veterinary; D047748:Pituitary ACTH Hypersecretion / Q000097:blood / Q000473:pathology / Q000662:veterinary*; D010911:Pituitary Neoplasms / Q000097:blood / Q000473:pathology / Q000662:veterinary*; D011333:Pro-Opiomelanocortin / Q000097:blood*; D011933:Reagent Kits, Diagnostic / Q000662:veterinary
chemical_list: D011933:Reagent Kits, Diagnostic; D011333:Pro-Opiomelanocortin; D000324:Adrenocorticotropic Hormone; D003348:Cortisone