Anatomy of a Lung:
- Bronchi
- To
- 17 divisions
- To
- Terminal bronchioles
- To
- Respiratory bronchioles
- To
- Alveolar ducts
- To
- Alveoli - where gas exchange takes place
Lung Cancer Etiology:
83% of cases are smoking related (risk is reduced after cessation)
Occupational - asbestos, coal tar, arsenic, nickel, uranium, chromate,
vinylchloride
Radon - gas from earth which is usually the cause of lung cancer for
non-smokers. Radon detectors can be bought and ventilation can be improved.
Air pollution
Predisposing conditions - scars, fibrosis
Lung Cancer:
168,000 new cases/per year
146,000 deaths/per year
Incidence in Women are Increasing
| Year |
Male: Female |
| 1950 |
20:1 |
| 1974 |
4:1 |
| 1987 |
2.2:1 |
- 5-year survival is 13% overall (not so good)
The cost of Cigarette Smoking:
400,000 deaths/per year
$65 billion/per year in healthcare costs and lost productivity
Smoking causes chronic emphysema, kidney cancer, lung cancer, strokes,
and heart disease
The more you smoke, the higher your chances of getting any type of cancer
Cigars and pipes cause mainly head and neck cnacers
All forms of tobacco cause cancer
Lung Cancer Symptoms:
Asymptomatic - Abnormal Chest x-ray
Pulmonary symptoms
Cough
Hemoptysis - coughing up blood
Dysphea - shortness of breath
Chest pain
Regional impingement symptoms
Brachial plexus - the nerves going to your arms can be blocked by cancer,
which can affect your hands.
Sympathetic nerves
SVC
Phrenic nerve
Left recurrent laryngeal nerve
Esophagus
Heart
Pleura
Chest wall
Constitutional symptoms - fever, chills, weight loss
Metastatic symptoms - bone, liver, CNS
Pareneoplastic symptoms
Endocrine
Neuromuscular
Hypertrophic pulmonary osteoarthropathy
Migratory thrombophtebitis
Lung Cancer Metastasis:
Direct extension
Lymphatic spread
Hematogenous
Common sites:
Liver
Bone
Brain
All of the body organs could be involved when Lung Cancer metastasizes.
Two Main Types of Cancer Cells:
Small cell cancer
Non-small cell cancer
Lung Cancer Growth Rates:
Average cancer cell - .001 cm
30 doublings - 1 cm
40 doublings - 10 cm
Lung Cancer Screening:
- Chest x-ray
- Black is good (air)
- White is tumor (other than muscles or bones)
Sputum cytology - cough and spit in container
- Impact on natural history
Screening Spiral Chest CT:
- Low dose radiation
- Fast
- Inexpensive
- Detects tumor at earlier stage
Lung Cancer Diagnosis:
- History and physical
- Chest x-ray
- Sputum
- CT
- Bronchoscopy
- Transthoracic needle biopsy
- Mediastinoscopy
- Thoracotomy