Usefulness of desmopressin testing to predict relapse during long-term follow-up in patients in remission from Cushing’s disease

Recurrence of Cushing’s disease after successful transsphenoidal surgery occurs in some 30% of the patients and the response to desmopressin shortly after surgery has been proposed as a marker for disease recurrence. The aim of the present study was to evaluate the response to desmopressin over time after surgery. We tested 56 patients with Cushing’s disease in remission after transsphenoidal surgery with desmopressin for up to 20 years after surgery. The ACTH and cortisol response to desmopressin over time was evaluated in patients on long-term remission or undergoing relapse; an increase by at least 27 pg/mL in ACTH levels identified responders. The vast majority of patients who underwent successful adenomectomy failed to respond to desmopressin after surgery and this response pattern was maintained over time in patients on long-term remission. Conversely, a response to desmopressin reappeared in patients who subsequently developed a recurrence of Cushing’s disease, even years prior to frank hypercortisolism. It appears therefore that a change in the response pattern to desmopressin proves predictive of recurrence of Cushing’s disease and may indicate which patients require close monitoring

Prognostic factors in ectopic Cushing's syndrome due to neuroendocrine tumors: a multicenter study

Objective: Evidence is limited regarding outcome of patients with ectopic Cushing's syndrome (ECS) due to neuroendocrine tumors (NETs). DESIGN: We assessed the prognostic factors affecting the survival of patients with NETs and ECS. METHODS: Retrospective analysis of clinicopathological features, severity of hormonal syndrome, treatments from a large cohort of patients with NETs and ECS collected from 17 Italian centers. RESULTS: Our series included 110 patients, 58.2% female, with mean (\ub1s.d.) age at diagnosis of 49.5\u2009\ub1\u200915.9 years. The main sources of ectopic ACTH were bronchial carcinoids (BC) (40.9%), occult tumors (22.7%) and pancreatic (p)NETs (15.5%). Curative surgery was performed in 56.7% (70.2% of BC, 11% of pNETs). Overall survival was significantly higher in BC compared with pNETs and occult tumors (P\u2009=\u20090.033) and in G1-NETs compared with G2 and G3 (P\u2009=\u20090.007). Negative predictive factors for survival were severity of hypercortisolism (P\u2009<\u20090.02), hypokalemia (P\u2009=\u20090.001), diabetes mellitus (P\u2009=\u20090.0146) and distant metastases (P\u2009<\u20090.001). Improved survival was observed in patients who underwent NET removal (P\u2009<\u20090.001). Adrenalectomy improved short-term survival. CONCLUSIONS: Multiple factors affect prognosis of ECS patients: type of NET, grading, distant metastases, severity of hypercortisolism, hypokalemia and diabetes mellitus. BCs have the highest curative surgical rate and better survival compared with occult tumors and pNETs. Hypercortisolism plays a primary role in affecting outcome and quality of life; therefore, prompt and vigorous treatment of hormonal excess by NET surgery and medical therapy should be a key therapeutic goal. In refractory cases, adrenalectomy should be considered as it affects outcome positively at least in the first 2 years