324.2 𩺠åèç
324.2.1 é«é »èé»
324.2.1.1 Etiology
- Smoking #1 (80-85%)
- Radon #2
- Asbestos + multiplicative with smoking
- Air pollution PM2.5
- Occupational
- Genetic
324.2.1.2 Pathology
- NSCLC 85%: adenocarcinoma (most common), squamous, large cell
- SCLC 15%: smokers, central, fast-growing, neuroendocrine
324.2.1.3 LDCT Screening (USPSTF 2021)
- Age 50-80
- ⥠20 pack-years
- Current smoker or quit < 15 years
- Annual LDCT
324.2.1.4 NLST + NELSON Trials
- NLST: 20% mortality reduction with LDCT
- NELSON: 24-33% reduction (men/women)
324.2.1.5 NSCLC Molecular Testing
- EGFR (50% Asian adenocarcinoma; osimertinib)
- ALK (alectinib, brigatinib, lorlatinib)
- ROS1 (crizotinib, entrectinib)
- KRAS G12C (sotorasib, adagrasib)
- MET exon 14 (capmatinib, tepotinib)
- HER2 (trastuzumab deruxtecan)
- BRAF V600E (dabrafenib + trametinib)
- NTRK fusion (larotrectinib, entrectinib)
- RET fusion (selpercatinib, pralsetinib)
- PD-L1 (immunotherapy)
324.2.1.6 Paraneoplastic Syndromes
- SCLC: SIADH, Cushing (ACTH), LEMS, limbic encephalitis
- Squamous: hypercalcemia (PTHrP)
- Adenocarcinoma: hypertrophic osteoarthropathy, clubbing
- Trousseau: hypercoagulability
324.2.1.7 Pancoast Syndrome
- Apical tumor
- Shoulder + arm pain (C8/T1/T2)
- Horner syndrome
- Hand weakness/atrophy
324.2.2 ææ··æ·æ¯èŒ
| Feature | NSCLC | SCLC |
|---|---|---|
| % | 85% | 15% |
| Smoking | Variable | Strong (>99%) |
| Location | Peripheral (adeno) or central (squamous) | Central |
| Growth | Slower | Fast |
| Molecular | Driver mutations + IHC | TP53, RB1 universal |
| IHC | TTF-1, napsin (adeno); p40 (squamous) | Chromogranin, syn, CD56 |
| Paraneoplastic | Squamous â PTHrP; Adeno â HOA | SIADH, ACTH, LEMS |
| Treatment | Targeted + IO | Chemo + IO + RT |
324.2.3 Special Topics
324.2.3.1 EGFR Mutation in Asian Women Non-Smokers
- Prevalence 50% (vs 10-15% Caucasian)
- Often adenocarcinoma
- Targeted therapy effective