Severe Ectopic Adrenocorticotropic Hormone Syndrome Due to Pulmonary Carcinoid Tumor: A Case Report and Literature Review.

Background/objective: Pulmonary carcinoid tumors are a rare cause of Cushing's syndrome and usually present with an indolent course. Here, we present a case of rapid onset and severe Cushing's syndrome due to a typical pulmonary carcinoid tumor.

Case report: A 32-year-old woman developed diabetes, hypertension, and weight gain of 50 pounds over 3 months. Laboratory evaluation was significant for elevated cortisol and adrenocorticotropic hormone levels and levels were nonsuppressible on low and high-dose dexamethasone suppression tests. Chest computed tomography revealed a pulmonary nodule and biopsy showed a typical carcinoid tumor. She was treated with steroidogenesis inhibitors with a plan for surgical excision but developed worsening complications of hypercortisolemia. She eventually underwent cryoablation of the tumor, but unfortunately passed away just 6 months after her initial presentation.

Discussion: Cushing's syndrome in typical pulmonary carcinoid tumors is rarely seen and usually presents with mild hypercortisolism similar to Cushing's disease. Severe hypercortisolemia from typical pulmonary carcinoid tumors can represent a more aggressive pathology or metastatic disease. Severe Cushing's syndrome is associated with significant morbidity and mortality and requires rapid tumor localization as surgical resection can be curative.

Conclusion: This case highlights a rare presentation of severe Cushing's syndrome due to a typical pulmonary carcinoid.