title: A combined dexamethasone desmopressin test as an early marker of postsurgical recurrence in Cushing's disease.
abstract: BACKGROUND
  Recurrence of Cushing's disease (CD) after transsphenoidal surgery (TSS) occurs in about 25% of cases. Twenty percent of patients with immediate postsurgical corticotroph deficiency will present late recurrence.
  
  
  OBJECTIVE
  The aim of the study was to evaluate a coupled dexamethasone desmopressin test (CDDT) as a predictor of recurrence of CD.
  
  
  METHODS
  We conducted a prospective bicenter study (Marseille and Grenoble, France).
  
  
  METHODS
  We studied 38 patients treated by TSS for CD with a mean follow-up of 60 months.
  
  
  METHODS
  We evaluated 24-h urinary free cortisol, ACTH, and cortisol plasmatic levels and performed low-dose dexamethasone suppression test and CDDT 3 to 6 months after surgery and then yearly.
  
  
  METHODS
  After CDDT, ACTH ratio (ACTHr) was defined as (PeakACTH - BaseACTH)/BaseACTH. Cortisol ratio (Cortisolr) was defined as (PeakCortisol - BaseCortisol)/BaseCortisol. Basal values were observed after low-dose dexamethasone suppression test. Receiver operator characteristics curve defined ACTHr and Cortisolr giving the best sensitivity and specificity associated with recurrence.
  
  
  RESULTS
  Ten patients presented recurrence. ACTHr and Cortisolr were superior or equal to 0.5 in all patients with recurrence and in three of 28 patients in remission (100% sensitivity, 89% specificity). The test became positive in eight of 10 patients with recurrence 6-60 months before classical markers of hypercortisolism. Six patients with immediate postsurgical corticotroph deficiency presented recurrence. All of them presented CDDT positivity during the 3 yr after surgery, and recurrence 6 to 60 months after CDDT positivity.
  
  
  CONCLUSIONS
  CDDT is an early predictor of recurrence of CD and could be of particular interest in the first 3 yr after surgery, by selecting patients at high risk of recurrence despite falsely reassuring classical hormonal markers.
authors.affiliation: Department of Endocrinology, Hôpital de la Timone, 264 rue St. Pierre, Cedex 5, Marseille 13385, France. thierry.brue@mail.ap-hm.fr
authors.forename: Frederic
authors.initials: F
authors.lastname: Castinetti
authors.forename: Monique
authors.initials: M
authors.lastname: Martinie
authors.forename: Isabelle
authors.initials: I
authors.lastname: Morange
authors.forename: Henry
authors.initials: H
authors.lastname: Dufour
authors.forename: Nathalie
authors.initials: N
authors.lastname: Sturm
authors.forename: Jean-Guy
authors.initials: JG
authors.lastname: Passagia
authors.forename: Bernard
authors.initials: B
authors.lastname: Conte-Devolx
authors.forename: Olivier
authors.initials: O
authors.lastname: Chabre
authors.forename: Thierry
authors.initials: T
authors.lastname: Brue
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D003894:Deamino Arginine Vasopressin / Q000008:administration & dosage*; D003907:Dexamethasone / Q000008:administration & dosage*; D003940:Diagnostic Techniques, Endocrine; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008875:Middle Aged; D047748:Pituitary ACTH Hypersecretion / Q000097:blood / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000175:diagnosis; D011379:Prognosis; D012008:Recurrence; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D015415:Biomarkers; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D003894:Deamino Arginine Vasopressin; D006854:Hydrocortisone