What Is Lung Cancer?
A clear, medically reviewed definition and overview adapted from the U.S. National Cancer Institute (NCI) and other trusted sources.
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Overview & Definition
Lung cancer is a disease in which abnormal cells in the lung grow uncontrollably, forming tumors that can invade nearby tissue and spread (metastasize). Smoking is the leading cause, but lung cancer also occurs in never-smokers due to other risks (e.g., radon, exposures, genetics).
Major Types (NSCLC & SCLC)
- Non–Small Cell Lung Cancer (NSCLC): ~85–90%; includes adenocarcinoma, squamous, large cell; often tested for targetable alterations (e.g.,
EGFR,ALK,ROS1,BRAF,MET,RET,KRAS). - Small Cell Lung Cancer (SCLC): ~10–15%; typically more aggressive and strongly associated with tobacco.
Risk Factors
- Tobacco smoke (including secondhand)
- Radon gas exposure
- Occupational exposures (asbestos, diesel exhaust)
- Air pollution
- Family history and prior chest radiation
Not everyone with risk factors develops lung cancer; risk reduction (smoke-free, radon testing) helps.
Signs & Symptoms
- Persistent cough or coughing up blood
- Chest pain, shortness of breath, wheeze, hoarseness
- Frequent infections (bronchitis, pneumonia)
- Unexplained weight loss, fatigue
- Bone or neurologic symptoms in advanced disease
Screening
Low-dose CT (LDCT) can detect cancer earlier in high-risk people (age/smoking criteria). Discuss benefits/harms with a clinician.
Diagnosis & Staging
Diagnosis
Imaging (CT, PET/CT), and biopsy via bronchoscopy/needle/surgery. Pathology and biomarker testing (e.g., PD-L1, driver mutations) guide therapy.
Staging
- TNM staging (NSCLC) for tumor, nodes, metastasis.
- Limited vs Extensive (SCLC) based on spread.
Treatment Options
- Surgery (early NSCLC) ± systemic/radiation
- Radiation therapy (including SBRT)
- Chemotherapy (often platinum-based)
- Targeted therapy for actionable mutations
- Immunotherapy (checkpoint inhibitors) ± chemo
- Supportive/palliative care throughout
Prognosis
Depends on type, stage, biomarkers, and response. Earlier detection improves outcomes; modern targeted and immune therapies can extend survival in advanced disease.
Sources & Attribution
- NCI — Lung Cancer: cancer.gov/types/lung
- CDC — Lung Cancer: cdc.gov/lung-cancer
- MedlinePlus — Lung Cancer: medlineplus.gov/lungcancer.html
Educational only; not medical advice.
Lung Cancer
Lung cancer starts when cells in the lungs grow out of control. It includes two main groups—non-small cell (most common) and small cell. Finding it early can save lives, and support makes the journey lighter.
Overview
Non-small cell lung cancer (NSCLC) is the most common type. Small cell lung cancer (SCLC) is less common and tends to grow more quickly. Many NSCLC tumors have “biomarkers” (EGFR, ALK, ROS1, KRAS, etc.) that can be targeted with specific medicines.
Symptoms
- Persistent cough or coughing up blood
- Shortness of breath, chest pain, wheezing
- Unexplained weight loss, fatigue, recurrent infections
Early lung cancer may cause few or no symptoms—screening can catch it sooner in higher-risk people.
Causes & Risk Factors
- Tobacco exposure: current or past smoking; secondhand smoke
- Radon gas, air pollution, workplace exposures (e.g., asbestos)
- Family history and certain lung diseases
Screening & Early Detection
- Low-dose CT (LDCT): for people at higher risk based on age and smoking history—ask your doctor if you qualify.
- Quitting smoking (or never starting) remains one of the strongest ways to lower risk.
Diagnosis & Staging
- Imaging (CT/PET), bronchoscopy or needle biopsy to confirm cancer type
- Staging I–IV describes tumor size, nodes, and spread
- Biomarker testing (EGFR, ALK, ROS1, BRAF, KRAS, MET, RET, NTRK, PD-L1) guides targeted and immunotherapies
Treatment Options
- Surgery (stages I–II, some III)
- Radiation (including SBRT) to cure early disease or treat spots
- Chemotherapy for many stages; often with other treatments
- Targeted therapy for tumors with actionable mutations
- Immunotherapy (e.g., anti-PD-1/PD-L1) alone or with chemo in appropriate cases
- Clinical trials at many stages—ask early
Managing Side Effects
- Fatigue, cough, shortness of breath—pulmonary rehab, inhalers, and gentle exercise help
- Nausea/appetite loss—anti-nausea meds, small frequent meals
- Targeted/immunotherapy effects (rash, infusion reactions, immune-related issues)—report symptoms promptly
Faith, Mental Health & Community
Hope grows in community. Prayer, counseling, and support groups ease fear, while practical help (rides, meals) lightens the load.
Survivorship & Follow-Up
- Scheduled imaging and visits per your plan
- Breathing exercises, nutrition, movement most days
- Stay smoke-free; ask about cessation support if needed
Downloadable Guides
Save or print these for appointments and support groups.
đź“„ New Diagnosis Roadmap đź“ť Doctor Questions đź“Š Treatment & Side Effects TrackerPlain-language summary for education; your care team gives personalized advice.
- Frameworks from NCI/ACS and peer-reviewed guidelines adapted for clarity.