In: Anatomy and Physiology
Chief Complaint: 68-year-old man with a cough and dyspnea ("shortness of breath") for the past week.
History: Daniel McDonald, a 68-year-old white male with a 40-pack-year smoking history suffered from chronic bronchitis for which he had been on antibiotics for several months. Two weeks ago, he began coughing up a bloody sputum ("hemoptysis"). In the past week he's become increasingly short of breath. A routine chest X-ray revealed two silver dollar-sized opacities on the right side of the carina. Bronchoscopic examination revealed a tumor that was nearly occluding the right mainstem bronchus. A bronchial biopsy revealed the diagnosis: bronchogenic carcinoma.
Questions:
Top of Form
1. Define the term "bronchogenic carcinoma."
2. Ninety percent of all cancers arise from epithelial tissue. Why do you suppose this is?
3. Describe the structure of the bronchial epithelium.
4. What is the "mucociliary escalator"?
5. This man has a long history of infectious bronchitis. Why would this chronic smoker be especially susceptible to infections of the bronchi?
6. Explain why this man has bloody sputum ("hemoptysis").
7. Explain why this man has shortness of breath ("dyspnea").
8. If you examined the cancerous tissue under the microscope, how might the cells differ in appearance from normal bronchial epithelium?
9. How might this type of cancer metastasize (i.e. spread to other parts of the body)? In other words, by which routes might the cancer cells reach other organs?
10. Why is the surgical removal of a lung cancer so ineffective in halting the disease?