[A bronchial carcinoid tumor in a patient with a high level of serum carcinoembryonic antigen].

A 76-year-old man was admitted to our hospital with a cough and bloody sputum. The level of serum carcinoembryonic antigen (CEA) was high (528.6 ng/ml), and the chest X-ray film revealed a large mass shadow in the lower left lung field. Bronchoscopic examination revealed complete obstruction of the left basal bronchus by a polypoid tumor coated with a white necrotic substance. Histologic examination of a specimen of the tumor led to the diagnosis of carcinoid. Left lower lobectomy and S5 segmentectomy were done. The operative diagnosis was also histologically carcinoid tumor. Immunohistochemical staining for CEA showed strong reactivity in tumor cells. The serum CEA level was normal when measured 2 months after the operation. Therefore, the excess serum CEA measured before the operation was probably secreted by tumor cells.