Persistent Adrenocorticotropin Response to Desmopressin in the Early Postoperative Period Predicts Recurrence of Cushing’s Disease

Abstract

Patients with Cushing's disease (CD) often show an ACTH and cortisol response to desmopressin (DDAVP). We tested whether persistence of a positive response to DDAVP after successful surgery identifies patients at risk of CD recurrence. We prospectively included all CD patients who had a positive response to DDAVP before successful surgery from 1995 through 2007. The study was performed at a university hospital. One hundred seventy-four patients with CD, 148 women and 26 men, mean age 36.1 +/- 0.8 yr, were studied. The median follow-up after surgery was 58 months (interquartile range 22-93 months). DDAVP test was performed immediately before and after surgery. An ACTH and cortisol increment of at least 30 and 20% above baseline, respectively, were considered as a positive response to DDAVP. The risk of CD recurrence was analyzed according to the postoperative hormonal response to DDAVP. Recurrence of CD occurred in 19 patients (10.9%). The recurrence-free survival at 5 yr was 89.8% [95% confidence interval (CI) 84.2-95.4]. Patients with a positive ACTH response had a 5-yr recurrence-free survival of 82.6% (95% CI 70.6-94.6%) as compared with 94.0% (95% CI 88.2-99.8%; P < 0.01) in patients without it. Multivariate analysis showed that persistence of a positive ACTH response to DDAVP was significantly associated with CD recurrence. Positive ACTH response to DDAVP after surgery is associated with an increased risk of CD recurrence. However, the specificity and predictive value of this finding are low.