Lung cancer Flashcards
What are the two broad categories of lung cancer?
Non-small cell and small cell
What cell type do non-small cell and small cell lung cancers arise from?
They are all carcinomas, so arise from epithelial cells.
What is the epidemiology of non-small cell and small cell lung cancer?
Small cell 20%; non-small cell 80%
What is the epidemiology of lung cancer: Common? Mortality? Gender?
Most common fatal malignancy in the West, 35 000 deaths in the UK per year. 3 times more common in men.
What are the three main types of non-small cell lung cancer?
Squamous cell carcinoma, adenocarcinoma, large cell carcinoma.
What is the difference in pathophysiology between sub-types of non-small cell lung cancer?
- Adenocarcinomas: from glandular epithelium and tends to involve the periphery, metastasise earliest
- Squamous cell carcninoma: tends to involve central airways, metastasise later
- Large cell carcinoma: undifferentiated carcinoma arising from transformed epithelial cells. Tends to begin in the periphery and grows fast
What is small cell lung cancer?
Epithelial cell cancer of neuroendocrine Kulchitsky cells of the lung aka oat cell carcinoma.
What is the pathophysiology of small cell lung cancer?
Arises in central lung, often with mediastinal involvement. Associated with early dissemination and metastasise.
What is the aetiology of small AND non-small cell lung cancer? (x3)
- Cause genetic alterations that result in neoplastic transformation
- Smoking
- Occupation exposures such as polycyclic hydrocarbons, asbestos, nickel, chromium, cadmium and radon (radioactive decay product of uranium)
- Atmospheric pollution
What are the symptoms of lung cancer? (x4 (x4 local invasion))
- Similar for small and non-small cell; may be asymptomatic
- DUE TO PRIMARY: dry cough, SOB, haemoptysis, chest pain, recurrent pneumonia
- DUE TO LOCAL INVASION: e.g., brachial plexus if the tumour is in the apex (Pancoast tumour) causing pain in shoulder or arm; left recurrent laryngeal nerve causing hoarseness and bovine cough (non- explosive cough of someone unable to close their glottis); oesophagus leading to dysphagia; heart leading to palpitations and arrythmia
- DUE TO METASTASIC DISEASE: weight loss, fatigue, bone pain
- DUE TO PARANEOPLASTIC SYNDROME: weakness, lethargy, seizures, muscle fatiguability
What type of lung cancer are most Pancoast tumours?
Non-small cell lung cancer.
What is paraneoplastic syndrome?
Due to cancer producing chemical signalling molecules such as hormones or cytokines or by an immune response against the tumour.
What are the signs of lung cancer? (x5 (x3 local invasion))
- Fixed monophonic wheeze
- Signs of collapse, consolidation or pleural effusion.
- DUE TO LOCAL INVASION: superior vena cava compression (facial congestion, distension of neck veins, upper limb oedema), brachial plexus (wasting of small muscles of the hand), sympathetic chain (Horner’s syndrome (pupillary miosis, ptosis, facial anhidrosis))
- DUE TO METASTASES: supraclavicular lymphadenopathy, hepatomegaly
- DUE TO PARANEOPLASTIC SYNDROME: hypertrophic osteoarthropathy (clubbing, painful swollen wrists and ankles from periosteal new bone formation)
How may lung cancer present on CXR? (x5)
Nodules (coin lesions – round well-circumscribed lesion) or mass, lobal collapse (atelectasis), pleural effusion, features of lymphangitis carcinomatosis, hilar lymphadenopathy.
What is lymphangitis carcinomatosis? Presentation on CXR?
Diffuse infiltration and obstruction of pulmonary parenchymal lymphatic channels by tumour. CXR shows reticulonodular opacification and associated with very poor prognosis.
