Overview
Lung cancer is the leading cause of cancer death in the UK and worldwide. There are two main types: non-small cell lung cancer (NSCLC, ~85% of cases) including adenocarcinoma and squamous cell carcinoma, and small cell lung cancer (SCLC, ~15%). SCLC grows and spreads more quickly. Smoking is the dominant cause but never-smokers are increasingly affected.
How common is it?
Lung cancer is the third most common cancer in the UK with around 48,000 new cases per year. It causes more cancer deaths than breast, colon, and prostate cancers combined. Survival remains poor because most cases present at an advanced stage.
Causes and risk factors
Tobacco smoke is responsible for approximately 72% of lung cancer cases. Carcinogens in smoke cause DNA mutations in bronchial epithelial cells, leading to malignant transformation.
Common risk factors
- Cigarette, cigar, or pipe smoking (dose and duration-dependent)
- Passive smoking
- Radon gas (second most common cause after smoking, especially in granite geology areas)
- Occupational exposure: asbestos, arsenic, chromium, nickel, silica, diesel exhaust
- Air pollution (WHO Group 1 carcinogen)
- Family history and genetic factors
- Previous lung disease (COPD, pulmonary fibrosis)
- Never-smokers (~13% of UK lung cancers): EGFR, ALK, ROS1 mutations more common
Symptoms
- Persistent new cough or change in existing cough
- Haemoptysis (coughing up blood)
- Persistent breathlessness
- Chest pain or shoulder pain
- Unexplained weight loss and fatigue
- Recurrent chest infections
- Hoarseness (recurrent laryngeal nerve involvement)
- Superior vena cava obstruction: facial swelling, arm swelling, headache
- Finger clubbing
When to see a doctor
See a doctor urgently for haemoptysis at any age, or for any new respiratory symptom lasting more than 3 weeks in a smoker over 40. NICE 2-week-wait pathway applies to anyone with unexplained haemoptysis or two or more of the relevant symptoms.
Diagnosis
Chest X-ray and CT thorax, abdomen, and pelvis. PET-CT for staging. Histological diagnosis by bronchoscopy, CT-guided biopsy, or EBUS (endobronchial ultrasound for mediastinal nodes). Molecular testing (EGFR, ALK, ROS1, PD-L1) for all advanced NSCLC to guide targeted therapy.
Treatments
Surgery (curative intent)
Lobectomy or pneumonectomy for stage I and II NSCLC. Video-assisted thoracoscopic surgery (VATS) is now standard. Curative in approximately 70 to 90% of stage I disease.
Targeted therapy
Oral EGFR inhibitors (osimertinib) and ALK inhibitors (alectinib, crizotinib) produce dramatic responses in molecularly selected patients. First-line for EGFR-mutant and ALK-positive advanced NSCLC.
Immunotherapy
Anti-PD-1 and anti-PD-L1 checkpoint inhibitors (pembrolizumab, nivolumab, atezolizumab) produce durable responses in a subset of patients and have transformed advanced NSCLC management.
Chemotherapy
Platinum-based doublet chemotherapy (carboplatin/pemetrexed, cisplatin/gemcitabine) remains standard for advanced NSCLC without targetable mutations. First-line in SCLC combined with atezolizumab.
Radiotherapy
SABR (stereotactic ablative radiotherapy) is curative in stage I NSCLC if surgery is not possible. Concurrent chemoradiotherapy for stage III disease. Palliative radiotherapy controls haemoptysis, pain, and SVC obstruction.
Self-care and lifestyle
- Stop smoking immediately — even after a lung cancer diagnosis, stopping improves treatment outcomes and survival
- Maintain physical activity and nutrition to tolerate treatment
- Test your home for radon if you live in a high-risk area (PHE UK radon map available)
- Consider lung cancer screening CT if eligible (current smoker or ex-smoker over 50 — NHS pilot programme)
Prevention
Not smoking is the most powerful preventive action. Radon reduction measures in high-risk homes, occupational exposure controls, and air pollution reduction are additional measures.