Bronchogenic carcinoma is a malignant neoplasm of the lung arising from the epithelium of the bronchus or bronchiole.

Bronchogenic carcinomas begin as a small focus of atypical epithelial cells within the bronchial mucosa. As the lesion progresses, the atypia becomes frankly malignant and the neoplasm grows in size. The neoplasm may grow into the bronchial lumen, along the mucosa or into the bronchial wall and adjacent lung parenchyma. Eventually the neoplasm spreads to regional lymph nodes and distant organs such as the liver, brain and bone. Most bronchogenic carcinomas form a mass in or near the hilus. Some neoplasms, especially the adenocarcinomas, form a mass in the periphery of the lung. Refer to Figure 15-42 in your textbook. The following classification scheme represents the major histologic types of bronchogenic carcinoma. Refer to Table 15-10 in your textbook.