46. PAS-Respiratory Pathophysiology
Lung Cancer Intro:
• Most common & fatal cancer (internal
malignancy)
• Kills more people than colorectal,
breast, and prostate cancers combined.
• Significant increase in incidence..
(developing countries*)
• Now Increasing in females > breast
cancer.
• 90% of lung cancers are related to
smoking..! (passive smoking in 5%)
• Mutagen sensitive genotype : P-450
enzyme
• Poor prognosis ~ 5% 5y survival *
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48. PAS-Respiratory Pathophysiology
Lung Cancer & Smoking:
• Proportional to duration, amount & quality of smoking &
deep inhaling.
• 90% are smokers and 10% are non smokers
• 20 fold risk if >40cigarettes per day
• >100 fold combined with Asbestos, coal, radon, etc.
• Atypical cells in sputum in 96.7% of smokers - 0.9% in non
smokers.
• Smoke has several irritants & carcinogens.
– Initiators – Benzo[o]pyrenes
– Promoters – Phenol derivatives
– Radioactive substances – Polonium, C14, K40
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50. PAS-Respiratory Pathophysiology
Types of Bronchogenic Ca.:
• Bronchogenic Carcinoma (95%)
– Small cell ca. SCC – 15-20% (oat cell carcinoma)
– Non Small cell NSCC– 80%
• Squamous cell carcinoma – 20-30%
• Adeno carcinoma – 30-40%
• Large cell anaplastic carcinoma
• Clinical / prognostic classification:
SCC - small cell Ca
Early spread
Surgery not possible.
Responds to chemo
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Non-SCC
Late spread – localized
Staging & Surgery
Does not respond to chemo.
59. PAS-Respiratory Pathophysiology
TNM: Staging of Lung Ca.
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T – Tumor (T1-4)
N – Node (N1-3)
M – Metastasis (M0-1)
Lung Cancer Staging:
I - T1 N0 M0
II - T1 N1 M0
III - Tn N2 M0
IV - Any M1
Based on Anatomical structure involved.
63. Bernie Banton
Asbestosis victim died Aug 2007.
Had Asbestosis, asbestos-related pleural
disease (ARPD),
stomach cancer & Peritoneal mesothelioma.
He became the face of the fight to get
compensation for affected workers and won
his final victory less than a week before his
death..!.
Mr Banton was awarded Order of Australia.
“until they put me in the box, I'll be out there fighting…!".
-- Bernie Banton, in his speech to ABC.
Commitment always wins….!
64. PAS-Respiratory Pathophysiology
Clinical Case 1:
A 28y Indonesian student presents with weight loss over a four-
month period and the recent onset of fever and chills at night.
Had several courses of antibiotics from his GP without
improvement. Admission chest x-ray revealed an irregular opacity
of the right apical lobe of lung with pleural effusion. Clinical
examination revealed cervical and axillary lymphadenopathy.
What is the likely problem? Chronic, infection, TB.
country of origin? Epidemiology.
What further tests? Bacterial culture, biopsy, PCR.
What is the prognosis? resistant, imm, risk factors.
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Tuberculosis
65. PAS-Respiratory Pathophysiology
Clinical Case 2:
• An 18y student from Tully, presented with wheezing and
difficulty in breathing. These attacks occurred
intermittently since childhood worse during winter. An x-
ray of the chest was normal, but lung function tests
during attack demonstrated a markedly decreased
FEV1, which improved significantly after he inhaled
bronchodilator. The patient was prescribed
bronchodilator & steroid inhalers which some relief, but
the patient continued to experience episodes of
breathlessness in the coming years.
• What is the likely problem? Chronic, recurrent, seasonal
• Why many attacks ? hypersensitivity/allergy.
• What is the prognosis? Nature, preventive only.
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Asthma
66. PAS-Respiratory Pathophysiology
Clinical Case 3:
• A 41y man was brought to emergency with high fever, shaking chills,
coughing up rusty sputum. On history, he'd been fine the day before
but that morning he had begun to shake uncontrollably and felt
alternately cold then hot and sweaty. His chest hurt on breathing. On
examination, thin white male who was anxious and mildly cyanotic,
tachypnea, fine rales and decreased breath sounds by auscultation
over the right lower chest. Temp100.2°F, but his pulse was normal.
WBC high, with 70% polys, 18% bands, and 12% lymphocytes.
Blood gases hypoxia & respiratory alkalosis. sputum gram-positive
diplococci.
• What is the problem? Acute infection of lungs – pneum.
• What & Why is he cyanotic? Co2 excess. Gas exch.
• Fine rales over RLL? Fluid – lobar pneumonia.
• Why his WBC count is high? – Acute inflammation.
• Gram Positive Diplococci ? – common, Strep. pneumoniae.
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Pneumonia
67. PAS-Respiratory Pathophysiology
“A good scare is worth more to
a man than good advice."
- Edgar Watson Howe - Country Town Sayings (1911)
That’s why we have
Exams!
68. PAS-Respiratory Pathophysiology
Learning Objectives:
• Respiratory anatomy, upper & lower resp. tracts.
• Review the process of ventilation & respiration.
• Pulmonary function tests (FVC, FEV1, FEV1/VC)
• Overview of chest radiograph & imaging.
• Respiratory infections - pneumonia and TB.
• Overview of obstructive and Restrictive
pulmonary disorders, Asthma, COPD, Fibrosis.
• Describe respiratory failure and its causes *
• Lung cancer, etiology, types and features.
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