Cushing syndrome secondary to ectopic adrenocorticotropic hormone secretion: The University of Texas MD Anderson Cancer Center Experience

BACKGROUND: Cushing syndrome (CS) secondary to ectopic adrenocorticotropic hormone (ACTH) secretion (EAS) has been described in association with a variety of tumors. The current experience with this syndrome was based on a few case series and individual case reports. Limited data were available about the tumors associated with CS-EAS in a cancer center setting. In this report, the authors have described their experience with CS-EAS at The University of Texas MD Anderson Cancer Center to further enhance the current understanding and management of this syndrome. METHODS: This was a retrospective review of 43 patients with CS-EAS who were diagnosed between 1979 and 2009 at The University of Texas MD Anderson Cancer Center. RESULTS: Different neuroendocrine tumors were associated with CS-EAS. Twenty-one patients (48.9%) had tumors located in the chest cavity, with bronchial carcinoid and small cell lung cancer representing the 2 most common causes. The ACTH source remained occult in 4 patients (9.3%) despite extensive workup. Clinical presentation varied, and the classic features of CS were not evident in some patients. Death occurred in 27 patients (62.8%), and the median overall survival was 32.2 months. Major morbidities included new-onset or worsening hyperglycemia (77%), symptomatic venous thromboembolism (14%), and infections (23%). CONCLUSIONS: In patients with CS-EAS who attended a comprehensive cancer center, tumors originating in the chest cavity were the leading tumors associated with this syndrome. The authors suspect that CS-EAS is under reported because of the atypical presentation in some patients. Thus, they suggest careful evaluation of patients with neuroendocrine tumors to avoid missing coexisting CS-EAS.