Lung Cancer Flashcards
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
What is the survival rate for lung cancer
70% 5 year survival with successful surgery and a small tumour
name other treatments for lung cancer
- Radical radiotherapy
- palliative radiotherapy
- chemotherapy
- immunotherapy
- adjuvant chemotherapy
- Neo-adjuvant chemotherapy
Describe radical radiotherapy
May be useful in squamous cell carcinoma where surgery not possible (lymph nodes involved, patient declines or not fit)
What are the complications of radical radiotherapy
- Pneumonitis (early)
- fibrosis (late)
- oespheogitis
what is palliative radiotherapy used for
To relieve pain, haemoptysis, neurological problems (brain or spinal metastases
describe chemotherapy use in lung cancer
- Cisplatin, pemetrexed, gemcitabine
- Oral therapy: EGFR antagonists like gefitinib, erlotinib
- ALK (anaplastic lymphoma kinase) mutation: Crizotinib, ceritinib, alectinib
- Newer agents: atezolizumab, durvalumab
- T790M mutation: osimertinib
what immunotherapy can be used
pembrolizumab (for PD-L1 positive tumours)
when is adjuvant chemotherapy given
Chemotherapy given after surgery to try to reduce chance of recurrence – usually if disease is found in a hilar lymph node
When is Neo-adjuvant chemotherapy given
Chemotherapy given before surgery to try to make sure that the cancer is as well controlled as possible
Name some other palliative therapies
- Endobronchial laser to relieve obstruction, breathlessness, haemoptysis
- Stenting to relieve breathlessness
- Endobronchial radiotherapy (brachytherapy)
Name some general palliative treatments
- Painkillers
- Antitussives
- Oxygen
- Steroids
Why is it important to have histopathology of lung cancer
- To differentiate between small cell lung cancer and large cell lung cancer
Where does small cell carcinoma differentiate from
Arise from endocrine cells (Kulchitsky cells), often secreting polypeptide hormones
What tumours spread to the lungs
- stomach
- pancreas
- breast
Where does lung cancer metastasise to
- the other lung
- adrenal gland
- bones
- brain
- liver
What pareneoplastic syndrome is seen in adenocarcinoma
- gynaecomastia
- hypertrophic pulmonary osteoarthropathy (HPOA)
