Ectopic adrenocorticotrophic hormone syndrome initially presenting as abnormal mental behavior caused by thymic carcinoid: a case report

Thymic carcinoid is a rare highly differentiated neuroendocrine neoplasm, which can manifest as endocrine disorders caused by ectopic adrenocorticotrophic hormone (ACTH) syndrome. Although clinical manifestations such as hypertension and hypokalemia are common manifestations in patients with ectopic ACTH syndrome, clinicians should also be aware of the mental and behavioral abnormalities that may initially appear in patients. It is extremely rare for patients with ectopic ACTH syndrome caused by thymic carcinoid to concurrently exhibit abnormal mental behavior, especially as the initial clinical manifestation of the tumor. Studies have suggested that abnormal mental behavior may be related to elevated blood cortisol levels.