327.3 🏥 內科專科考前版

327.3.1 Mechanistic Deep Dive

327.3.1.1 Sub-Solid Nodule Biology

  • Lepidic growth (along alveolar walls)
  • AAH → AIS → MIA → IA continuum
  • Different driver mutations possible (EGFR more common)
  • Slow growth advantage allows surveillance

327.3.1.2 CT Density Measurement

  • Hounsfield units
  • Fat: -100 to -50
  • Water: 0
  • Air: -1000
  • Calcium: +100 to +200
  • Soft tissue (solid): 30-60

327.3.2 Recent Trials & Updates

327.3.2.1 2024 Fleischner Society Updates

  • Streamlined guidelines
  • AI integration
  • Volumetric measurement

327.3.2.2 Radiomics + AI

  • Machine learning analysis of CT features
  • Improved risk prediction
  • Lung-RADS AI integration

327.3.2.3 Robotic Bronchoscopy Long-Term Data

  • Monarch, Ion platforms
  • 70-80% diagnostic yield for peripheral lesions
  • Reduced complications vs CT-guided

327.3.2.4 Liquid Biopsy in SPN

  • ctDNA detection in early-stage cancer
  • CancerSEEK, Grail Galleri studies
  • Sensitivity limited for SPN

327.3.2.5 CTC (Circulating Tumor Cells)

  • Research mostly
  • Future role

327.3.3 High-Yield Specialist Points

327.3.3.1 Pneumothorax After CT-Guided Biopsy

  • ~ 25% incidence
  • ~ 50% need chest tube
  • Risk factors: emphysema, deeper lesion, smaller lesion
  • Most resolve spontaneously

327.3.3.2 Bronchoscopy Yield for SPN

  • Standard bronchoscopy: 20-30% for peripheral
  • Navigational + EBUS + ROSE: 50-70%
  • Robotic: 70-80%

327.3.3.3 Pseudoprogression in Sub-Solid Nodules

  • Inflammation post-biopsy or post-RT
  • Resolves
  • Distinguish from true progression

327.3.3.4 PET-CT False Negatives

  • Nodule < 8 mm (poor spatial resolution)
  • Adenocarcinoma in situ / well-differentiated
  • Carcinoid tumor
  • Sub-solid nodules

327.3.3.5 Endobronchial Ultrasound (EBUS-TBNA)

  • Mediastinal staging
  • Hilar lymph nodes
  • Not for SPN itself but for staging adjacent

327.3.3.6 Liquid Biopsy Trials

  • Detect rare lung cancer mutations in blood
  • Adjunct, not definitive
  • Future role evolving

327.3.3.7 Surgical Resection of SPN

  • VATS wedge resection
  • Frozen section if uncertain
  • Lobectomy if confirmed cancer
  • Single-stage if high probability

327.3.3.8 Lung-RADS Updates

  • Annual updates
  • 2024 incorporates more sub-solid criteria
  • AI-assisted reading

327.3.4 Pearls

  • SPN ≀ 3 cm; mass > 3 cm
  • Sub-solid > solid for same size (malignancy probability)
  • Benign calcifications: central, laminated, popcorn, diffuse
  • PET-CT SUVmax > 2.5 concerning; false neg for small, sub-solid, AIS, carcinoid
  • Fleischner 2017: size + risk + solid/sub-solid guides
  • Lung-RADS: LDCT screening categories
  • Robotic bronchoscopy: 70-80% peripheral yield
  • Adenocarcinoma spectrum: AAH → AIS → MIA → IA