Lung Cancer Flashcards
(40 cards)
What increases the risk of lung cancer
- Smoking
- Asbestos
- Radiation (environmental radon)
- Arsenic
- Chromium
- Coal tar and oils
- Iron oxides
- Recent study: pollution
What is the increase in passive smoking on lung cancer
- passive smokers have a 1.5 fold increased risk
- but this depends on the quantity inhaled
how much lung cancers occurs in non-smokers
15% of lung cancers occurs in non-smokers
if you stop smoking what happens to the risk of lung cancer
- stopping smoking does not lower the risk back down to non-smoking levels - but it does increase life expectancy
What are the genetic mechanisms of lung cancer
- Activation of oncogenes e.g. KRAS, myc family of oncogenes. EGFR and ALK mutations
- Inactivation of tumour suppressor genes e.g. p53
- Autocrine growth factors e.g. derivatives of nicotine found in smoke
- Inherited predisposition (details not fully known)
what are the types of lung cancer
- Small cell (oat cell) lung cancer (SCLC) 10%
- Non small cell lung cancer (NSCLC)
Name the types of non small cell lung cancer
- Squamous cell carcinoma 20-30%
- Adenocarcinoma 40-50%
- Large cell carcinoma 10-15%
What are the features of small cell carcinoma
- Aggressive, early spread, usually inoperable as spreads easily
- May respond to chemotherapy due to rapidly dividing cells
- Endocrine cells: hormones produced
who is squamous cell carcinoma tend to be in
smokers
- often cavities
describe large cell carcinomas
- Undifferentiated
- Early metastasis
Name an example of large cell carcinoma
- bronchoalveolar cell (adenocarcinoma in situ)
what does a bronchoalveolar cell (adenocarcinoma in situ) resemble
- may resemble a pneumonia
What are the indications that call for an urgent CXR if you suspect lung cell carcinoma
- haemoptysis
Any of the following for greater than 3 weeks unexplained:
- cough
- chest/shoulder pain
- dyspnoea
- weight loss
- chest signs
Other things
- hoarseness - tumour in left side compressing recurrent laryngeal nerve
- clubbing
- features of mets
- Supraclavicular / Cervical lymphadenopathy
What are chest signs of lung cancer
- Visible swelling
- Facial swelling
- Distended veins - superior vena cava disrupted syndrome
- Reduced expansion
- Dullness, ↓TVF and VR
- Wheeze – esp. unilateral
- Reduced breath sounds
what paraneoplastic syndromes can be caused by small cell lung cancer
- Cushing’s syndrome (ectopic ACTH)
- SIADH
- Lambert Eaton myasthenic syndrome
- Limbic encephalitis
- Cerebellar syndrome
Any – but more common in SCLC
- Dermatomyositis
What paraneoplastic syndrome is in squamous cell carcinoma
- parathyroid hormone-related protein (PTH-rp) secretion causing hypercalcaemia
- clubbing
- hypertrophic pulmonary osteoarthropathy (HPOA)
hyperthyroidism due to ectopic TSH
what should cause a 2 week wait referral for lung cancer
If the CXR or CT scan suggests lung cancer including:
- pleural effusion
- slowly resolving consolidation
If the CXR (or CT) is normal, but there is a high clinical suspicion of lung cancer, the patient should be referred
When should patients be referred whilst having to wait for a CXR
Patients should be referred whilst awaiting a CXR in the presence of:
- Persistent haemoptysis in smokers/ex-smokers older than 40 years
- signs of superior vena caval obstruction (swelling of the face/neck with fixed elevation of jugular venous pressure)
- Stridor
Emergency referral should be considered for patients with superior vena cava obstruction or stridor.
What investigations do you use to stage and diagnose lung cancer
- CT of chest
- bronchoscopy
- CT guided biopsy
- PET scan
- MRI scan for pancoast tumours not used so much for lung cancer
- blood tests - urea and electrolytes for IV contrast which can be dangerous for people in renal impairment
What does staging involved when using a CT scan
“Staging” CT of chest – includes upper abdomen to cover liver, adrenals and kidneys
What are the other staging investigations can be used
- Transbronchial “blind” FNA
- EBUS guided FNA - can look at lymph nodes or tumours that are sitting near the bronchi, can put a fine needle and take samples
- EUS guided FNA
- Mediastinoscopy
- Bone scan
- Brain CT/MRI
Describe the TNM staging for lung cancer
T – based on size and location of tumour.
- T1 is a small peripheral tumour which may be removed surgically (Stage 1 or 2)
- T4 is an advanced large tumour invading e.g. heart (Stage 3)
N – depends on which lymph nodes are involved
- N1 – hilar (Stage 2),
- N2 – mediastinal
- N3 – contralateral (Stage 3)
M – if metastases are present: M1 (Stage 4)
- Common sites: liver, lungs, adrenals, brain, bones
What is the only curative treatment for lung cancer
- Surgery
describe what lung cancers can be surgically treated
- For localised tumours that are not invading other organs e.g. heart, bones
- No signs of spread – have to perform a PET scan
- It is the only chance of a “cure”
- 5 – 10% are suitable
