Bronchogenic carcinoma arises from the lung epithelium. It is most common in males aged 40-70 who smoke cigarettes. On chest x-ray, central tumors appear as masses in the hilum while peripheral tumors appear as solitary pulmonary nodules, usually in the upper lobes. Features suggesting malignancy include spiculated margins, lobulation, cavitation with thick walls, and growth over time. Radiography remains important for initial detection and assessment of complications.