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Lung cancer (Chapter 36: The Lung: III. Neoplasms) is responsible for more deaths (over 125,000 annually) in the United States than any other type of cancer. Chronic obstructive pulmonary disease (COPD, Chapter 35: The Lung: II. Toxic, Immunologic, & Vascular Diseases), which includes emphysema and chronic bronchitis, is the most common type of lung disease. It is second only to ischemic heart disease as a cause of chronic disability. Both lung cancer and COPD are related to cigarette smoking, which is discussed in Chapter 12: Disorders Due to Chemical Agents.
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Pneumonia and tuberculosis (Chapter 34: The Lung: I. Structure & Function; Infections) have decreased in importance as a cause of death in developed countries but remain serious problems in developing countries. Pneumocystis carinii pneumonia is the most common opportunistic infection in immunocompromised patients, including those with AIDS (Chapter 7: Deficiencies of the Host Response). Pulmonary embolism (Chapter 35: The Lung: II. Toxic, Immunologic, & Vascular Diseases) is a life-threatening complication of many clinical states and is usually secondary to venous thrombosis (see Chapter 9: Abnormalities of Blood Supply).