Bronchogenic carcinoma is the leading cause of death from cancer in men and women in the United States. Although the cause of this malignancy is probably multifactorial, approximately 85% of lung cancer deaths are attributable to cigarette smoking. Patients may present with symptoms of airway obstruction caused by central tumors, symptoms related to direct tumor invasion of surrounding structures, or symptoms produced by distant metastases. There are four major cell types: adenocarcinoma, squamous cell carcinoma, undifferentiated large cell carcinoma, and small cell carcinoma. Adenocarcinoma and undifferentiated large cell carcinoma are generally peripheral lesions manifesting as solitary nodules or masses, whereas squamous cell carcinoma and small cell carcinoma are typically central and may manifest as hilar masses, atelectasis, or pneumonia. The prognosis for patients with bronchogenic carcinoma is poor, with an overall 5-year survival of 10%-15%. In general, patients with squamous cell carcinoma have the best prognosis, those with adenocarcinoma and undifferentiated large cell carcinoma have an intermediate prognosis, and those with small cell carcinoma have the worst prognosis.