Chapter 9: Pulmonary Pathology
An adult who has never smoked or been around cigarette smoke is unlikely to have which of the following diseases?
A. Adenocarcinoma of the lung
B. Squamous cell carcinoma of the lung
C. Mature carcinoid tumor
D. Small cell carcinoma of the lung
Explanation: Most (roughly 85%) of lung carcinomas develop in patients who have smoked more than 20 pack-years (pack-year = packs-per-day × years of smoking). The two primary lung carcinomas that would be extremely rare in nonsmokers include squamous cell carcinoma and small cell carcinoma.
An adult smoker with bilateral lung nodules is unlikely to have which of the following diseases?
A. Primary lung carcinoma
B. Metastatic carcinoma from another organ
C. Bacterial or mycobacterial infection
Explanation: Primary lung carcinomas are rare, so the likelihood of having 2 separate clonal neoplasms primary in the lung, presenting at the same time, would be extremely rare. Much more likely would be infections or multi-focal metastases from a malignant neoplasm arising in another organ.
Functionally, the most important macromolecules in the lung are:
A. Carcinogens, chemokines, and thromboxane
B. Integrins, toll-like molecules, and collagen
C. Keratins, von Willebrand factor, and desmin
D. Mucin, elastin, and surfactant
Explanation: Mucin is critical to the muco-ciliary movement of dust and debris out of the lung. Elastin is critical to the lung’s elasticity, which reduces the work of breathing. Surfactant allows alveolar inflation by reducing the surface tension of water in the alveoli. The other polymers and small molecules are important structurally and functionally, but are not as important as mucin, elastin, and surfactant for normal lung function.