Lung and pleural cancers - recognition and referral
Exam Tips
- In UK exams, memorize the red flag: unexplained haemoptysis in age >=40 years -> 2-week-wait suspected lung cancer referral (not just routine imaging).
- For age >=40 years, urgent CXR within 2 weeks is triggered by either >=2 unexplained symptoms (cough, fatigue, breathlessness, chest pain, weight loss, appetite loss) or >=1 of these symptoms with smoking/asbestos risk.
- Finger clubbing, persistent/recurrent chest infection, supraclavicular or persistent cervical nodes, and thrombocytosis should push you toward urgent chest imaging.
- Normal chest X-ray does not fully exclude cancer; persistent concerning symptoms warrant further imaging (typically CT) and specialist discussion.
- State practical pathway steps in OSCE answers: include risk factors in referral letter, label urgency clearly, refer within 1 working day once decision is made, and safety-net missed appointments.
Definition
Lung and pleural cancers in UK primary care mainly refer to bronchogenic lung carcinoma and pleural mesothelioma, where early recognition is based on symptom patterns plus risk context (especially smoking and asbestos exposure). This is a recognition-and-referral diagnosis: chest X-ray is the first urgent test in most people aged 40 years and over with unexplained respiratory/systemic symptoms, and definitive diagnosis requires secondary-care tissue sampling.
Pathophysiology
Lung cancer usually develops through cumulative airway epithelial DNA damage (classically from tobacco smoke), progressing from dysplasia to invasive malignancy with potential lymphatic and haematogenous spread (commonly to brain and bone). Pleural mesothelioma is strongly linked to prior asbestos exposure; inhaled fibres reach pleura and drive chronic inflammation, mesothelial injury, and malignant transformation. Both diseases can cause local thoracic effects (airway obstruction, pleural involvement, chest pain, breathlessness) and systemic effects (weight loss, fatigue, prothrombotic state).
Risk Factors
- Age 40 years and over (key referral threshold in NICE suspected-cancer criteria)
- Ever smoked (major risk factor for lung cancer; also used as a risk modifier in referral criteria)
- Asbestos exposure (major risk factor for pleural mesothelioma)
- Male sex (epidemiologically higher mesothelioma incidence in current UK data)
- Previous or ongoing unexplained thrombocytosis/DVT may indicate underlying malignancy
Clinical Features
Symptoms
- Unexplained cough
- Unexplained shortness of breath
- Unexplained chest pain
- Unexplained fatigue
- Unexplained weight loss
- Unexplained appetite loss
- Persistent or recurrent chest infection
- Unexplained haemoptysis (especially high-risk red flag in age >=40)
- Possible metastatic presentation (e. g, bone pain, neurological symptoms suggesting brain metastases)
Signs
- Finger clubbing
- Supraclavicular lymphadenopathy
- Persistent cervical lymphadenopathy
- Chest signs consistent with lung cancer
- Chest signs compatible with pleural disease (mesothelioma pattern)
- Features of venous thromboembolism (including DVT) without clear alternative cause
Investigations
Management
Lifestyle Modifications
- Arrange referral promptly once criteria are met (send referral within 1 working day) and provide clear safety-net advice about worsening breathlessness, haemoptysis, chest pain, or missed appointments.
- Offer smoking cessation support at first contact to improve overall outcomes and peri-treatment fitness.
- Document occupational exposure history (especially asbestos) and communicate this in referral letters.
Pharmacological Treatment
Smoking cessation pharmacotherapy (adjunct while awaiting specialist pathway)
- Varenicline: days 1-3, 500 micrograms once daily; days 4-7, 500 micrograms twice daily; then 1 mg twice daily (usual 12-week course)
- Bupropion SR: 150 mg once daily for 6 days, then 150 mg twice daily (start 1-2 weeks before quit date; usual 7-9 weeks)
- Nicotine replacement therapy (example): transdermal patch 21 mg/24 h daily, stepped down over treatment course
Use according to BNF smoking-cessation guidance and patient factors. Contraindications/safety: bupropion is contraindicated in seizure disorders, current/past bulimia or anorexia nervosa, and other seizure-risk states; varenicline requires dose reduction in significant renal impairment and monitoring for neuropsychiatric adverse effects; avoid duplicative nicotine products without a structured plan.
Surgical / Interventional
- Diagnostic bronchoscopy with biopsy in secondary care
- CT-guided percutaneous lung or pleural biopsy
- Thoracoscopy/pleural biopsy when pleural malignancy is suspected
- Definitive oncological surgery (e. g, resection) considered only after specialist staging and MDT decision
Complications
- Metastatic spread, especially to brain and bone
- Venous thromboembolism (including DVT)
- Persistent/recurrent chest infection due to airway obstruction
- Progressive pleural disease with breathlessness and pain
- Late diagnosis leading to reduced curative options
Prognosis
Overall prognosis is poor: UK 5-year survival is below 10% for both lung cancer and pleural mesothelioma, so earlier recognition and rapid referral are critical for any chance of stage-shift and improved outcomes.