Since the first description of thymic carcinoid as a specific entity in 1972 by Rosai and Higa, approximately 92 cases of adrenocorticotropic hormone (ACTH)-producing thymic neuroendocrine associated with Cushing's syndrome (CS) have been described between 1980 and 2011. We report here three new cases of neuroendocrine tumor (NET) of thymus associated with ectopic production of ACTH along with review of recent literature.
All our three cases were middle age (2 male and 1 female) with clinical features of CS. Two of the three patients had hyperpigmentation. All the three underwent transsternal excision of thymic tumor.
The NET of the thymus associated with CS can occur at any age from 4 to 64 years; however, meta-analysis revealed that majority of cases occur between 18 and 40 years. There is no sex predilection for these tumors except for the NETs which are associated with MEN-1, which occurred predominantly in males.
Majority of these patients would present with clinical features of CS, although the severity and rapidity of onset would vary.
The ACTH-producing NET is a rare cause of CS and requires high suspicion to make an early diagnosis and is a locally aggressive disease that requires aggressive surgical resection. Adjuvant radiotherapy may be beneficial.
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