The efficacy of serum carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 15-3 (CA15-3), alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) levels in determining the malignancy of solitary pulmonary nodules.

We investigated the utility of the tumour markers carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 15-3 (CA15-3), alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) for the differential diagnosis of benign and malignant solitary pulmonary nodules in 42 hospitalized patients. Routine medical history and physical examination of each patient was performed and each patient also had a chest X-ray and a thoracic computed tomography scan. The following diagnostic procedures were also undertaken: bronchoscopy, transthoracic needle aspiration biopsy, sputum cytology and culture, analysis of sputum acid-fast bacilli and thoracotomy. Measurement of serum levels of tumour antigens by Immulite 2000 radioimmunoassay found that three tumour markers, CEA, CA125 and CA15-3, could be used in the diagnosis of malignant solitary pulmonary nodules. More research is now required involving a larger group of patients.