**_🫀🫁Cardio & Resp🫀🫁 - Lung Cancer Flashcards
What are the key epidemiological facts about lung cancer?
3rd most common cancer in the UK
48000 diagnoses/year
35000 deaths/year
Leading cause of cancer death
What groups of people are statistically more likely to get lung cancer?
Peak age 75-90
Males>females
Lower socioeconomic status
Smoking history strong indicator - duration, intensity, when stopped
Despite this, 10-15% patients with lung cancer never smoked
What other causes are there for lung cancer, other than smoking?
Asbestos - exposure associated with up to 2x risk
Radon - historically mining
Indoor cooking fumes
Chronic lung diseases
Air pollution
Fx/genetic factors
What is the basic pathogenesis of lung cancer?
Lung cancer may arise from all differentiated and undifferentiated cells
Interaction between inhaled carcinogens and epithelium of upper and lower airways - leads to the formation of DNA adducts - pieces of DNA covalently bound to a cancer-causing chemical
Persisting/misrepaired adducts result in mutations - cause genomic alterations
What are the various pathophysiologies of lung cancer?
- Squamous cell carcinoma (~30% of cases)
- Adenocarcinoma (~40%)
- Large cell lung cancer (~15%)
- Small cell lung cancer (~15%)
1-3 often grouped together as non-small cell lung cancer (NSCLC)
Outline squamous cell carcinoma lung cancer
30% of cases
Previously the most common
Originating from the bronchial epithelium - centrally located
(Coughing, haemoptysis, recurrent infections due to airway obstruction)
(Moderately fast - slower than small cell but can invade nearby structures early - better prognosis than small cell but worse than adenocarcinoma)
Outline adenocarcinoma lung cancer
40% of cases
Most common from 1980s onwards
Originates from mucus-producing glandular tissue- more peripheral
Accounts for most non-smoking lung cancer cases
(Later presentation with vague symptoms like shortness of breath/chest pain)
(Slower growing, can metastasize early, especially to bones and brain - generally better prognosis, especially if detected early)
Outline large cell lung cancer
15% of cases
Heterogenous group, undifferentiated
Often peripheral, but can be anywhere
(Non-specific symptoms; can cause chest pain, cough, or symptoms based on where it spreads)
(Aggressive, rapid growth, high likelihood of metastasis.
Poor prognosis due to rapid progression and late detection)
Outline small cell lung cancer
15% of cases
Originate from pulmonary neuroendocrine cells
Highly malignant
(Rapid onset of cough, weight loss, and paraneoplastic syndromes (e.g., SIADH, Cushing syndrome))
(Very fast growing, early and widespread metastasis.
Poorest prognosis, high recurrence rate even with treatment)
Name the 4 most important oncogenes in the pathogenesis of lung cancer, specifically mutations in them
Epidermal growth factor receptor (EGFR) tyrosine kinase
Anaplastic lymphoma kinase (ALK) tyrosine kinase
c-ROS oncogene 1 (ROS1) receptor tyrosine kinase
BRAF (downstream cell-cycle signalling mediator)
What is the significance of an Epidermal growth factor receptor (EGFR) tyrosine kinase mutation?
15-30% of adenocarcinoma
More so in women, Asian ethnicity, never-smokers
What is the significance of an Anaplastic lymphoma kinase (ALK) tyrosine kinase mutation?
2-7% of non-small cell lung cancer
Especially in younger patients and never-smokers
What is the significance in a c-ROS oncogene 1 (ROS1) receptor tyrosine kinase mutation?
1-2% of non-small cell lung cancer
Especially in younger patients and never-smoker
What is the significance of a BRAF (downstream cell-cycle signalling mediator) mutation?
1-3% of non-small cell lung cancer
Especially in smokers
What are the key symptoms of lung cancer?
Cough
Weight loss
Breathlessness
Fatigue
Chest pain
Haemoptysis
Can be frequently asymptomatic
What are the key features of advanced/metastatic lung cancer?
Neurological features:
Focal weakness, seizures, spinal cord compression
Bone pain
Paraneoplastic syndromes:
Clubbing, hypercalcaemia, hyponatraemia, Cushing’s
What is clubbing?
What is cachexia
Severe, rapid muscle loss
What is Pemberton’s sign?
What is Horner’s syndrome?
Decreased pupil size, a drooping eyelid and decreased sweating on the affected side of the face
What is the diagnostic strategy for suspected lung cancer?
Establish most likely diagnosis
Establish fitness for investigation and treatment
Confirm diagnosis and histological type
-genomic testing key if considering systemic treatment in NSCLC
Confirm staging
Who is in the lung cancer MDT?
Respiratory doctor
Radiologist
Pathology doctor
Thoracic surgeon
Oncologist
Palliative care
(Patient)
Who is currently eligible for lung cancer screening?
Current or ex-smokers aged between 55 and 74 are invited via their GP to attend a lung health check
Offered an appointment for a low dose CT scan
RMP pilot: Lung cancer detected in 29/1145 (2.5 %) participants scanned (stage 1, 58.6 %)
How is PET-CT useful?
Helps exclude occult metastases