Carcinoembryonic Antigen Elevation in Bronchial Foreign Body Patients Initially Misdiagnosed as Lung Cancer.

BACKGROUND: We report a case of chronic bronchial foreign body complicated by recurrent pulmonary infection with hemoptysis, initially misdiagnosed as lung cancer after laboratory tests revealed markedly elevated carcinoembryonic antigen levels. METHODS: Laboratory examination, contrast-enhanced chest CT scan, electronic bronchoscopy, and ultra-thin bronchoscopy were performed, confirming a bronchial foreign body (chili pepper skin). Symptoms resolved after removal of the foreign body (chili pepper skin) via electronic bronchoscopy. RESULTS: Carcinoembryonic antigen levels were significantly elevated. Chest CT scan revealed a high-density nodular shadow and calcification foci in the right lower lobe. Ultrathin bronchoscopy demonstrated a bronchial foreign body (chili pepper skin) visible in the basal segment of the right lower lobe. Pathological examination of bronchial tissue from the right lower lobe showed no tumor cells. CONCLUSIONS: It is necessary to pay attention to the calcification of the trachea and the differential diagnosis of lung cancer, especially when the level of carcinoembryonic antigen is increased.