Diagnosis and surgical treatment of ectopic adrenocorticotropic hormone-producing pulmonary tumors accompanied by Cushing syndrome.

Malignant pulmonary tumors are rarely accompanied by Cushing syndrome. We encountered 4 patients with adrenocorticotropic hormone (ACTH)-producing pulmonary tumors (3 with carcinoid and 1 with small cell carcinoma). All patients were females aged 33-76 years. In the 4 patients, diagnostic methods, surgical procedures, stage, outcome, and immunohistological findings were evaluated. Subtotal resection of the anterior lobe of the pituitary gland had been performed in 3 patients. However, ACTH did not decrease, and further examination revealed pulmonary tumors. Preoperative blood sampling by catheter examination was performed in 2 patients, of whom 1 showed increased ACTH. Intraoperative blood sampling showed increased ACTH in 1 patient. Lobectomy combined with mediastinal lymph node dissection was performed in 3 patients and lobectomy alone (video-assisted thoracoscopic surgery) in 1. All patients showed a decrease in ACTH after operation without tumor recurrence. Diagnosis is possible by measuring ACTH in pulmonary arterial wedge blood obtained by catherization or in pulmonary venous blood obtained during operation. Surgical resection is effective for ectopic ACTH-producing pulmonary tumors.