Lung Cancer
Also known as: Bronchogenic Carcinoma, Non-Small Cell Lung Cancer, Small Cell Lung Cancer
Lung cancer is the leading cause of cancer death worldwide, most commonly caused by smoking but also occurring in never-smokers. The two main types are non-small cell (NSCLC, ~85%) and small cell (SCLC, ~15%). Advances in screening, targeted therapy, and immunotherapy have significantly improved outcomes.
Symptoms
Causes
- Cigarette smoking (80–90% of lung cancer deaths)
- Secondhand smoke exposure
- Radon gas exposure (second leading cause)
- Occupational exposure to asbestos, diesel exhaust, and other carcinogens
- Genetic mutations (EGFR, ALK, ROS1, KRAS) — particularly in never-smokers
- Air pollution
Risk Factors
- Current or former cigarette smoking
- Secondhand smoke exposure
- Radon exposure in the home
- Family history of lung cancer
- Occupational carcinogen exposure
- Previous chest radiation therapy
Diagnosis
- Low-dose CT scan for screening high-risk individuals
- Chest X-ray
- Biopsy via bronchoscopy, CT-guided needle, or surgery
- PET-CT scan for staging
- Molecular testing for targetable mutations (EGFR, ALK, PD-L1)
Treatment
- Surgery (lobectomy, pneumonectomy) for early-stage NSCLC
- Stereotactic body radiation therapy (SBRT) for inoperable early-stage
- Chemotherapy with immunotherapy for advanced disease
- Targeted therapy for specific mutations (osimertinib for EGFR, alectinib for ALK)
- Immunotherapy (pembrolizumab, nivolumab, atezolizumab)
- Concurrent chemoradiation for locally advanced disease
Prevention
- Don't smoke, and quit if you do
- Avoid secondhand smoke
- Test your home for radon and mitigate if needed
- Get screened with low-dose CT if you meet high-risk criteria
- Minimize occupational carcinogen exposure
When to See a Doctor
- Persistent cough lasting more than 2–3 weeks
- You cough up blood, even a small amount
- Unexplained shortness of breath or weight loss
- You are a current or former smoker who has not been screened
Frequently Asked Questions
Related Conditions
Have questions about Lung Cancer?
Ask Mother Nature AI for personalized, evidence-based guidance.
Ask about Lung CancerMedical Disclaimer: This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider.
Content reviewed against peer-reviewed medical literature and clinical guidelines. Read our editorial standards.