L6.2 Drugs for lung cancer

Question 1

What is the most common cause of death from cancer?

Answer 1

90% from smoking

Question 2

Pathogenesis of Lung cancer

Answer 2

Question 3

Mutations required for carcinogenesis of solid tumours?

Answer 3

Multiple mutations required

Question 4

Pathological subtypes of lung cancer:

Answer 4

• Non-small cell lung cancers (85%)
  
  • After metastasis → poor prognosis
  • Adenocarcinoma (tumour from glandular structures)
  • Squamous cell carcinoma (main epithelial cell mutations)
  • Large cell undifferentiated carcinoma
• Small cell lung cancer (15%)

Question 5

Symptoms of lung cancer

Answer 5

• When symptoms shows → already locally/distantly spread
  
  • 50% at metastatic stage at diagnosis
• No pain fibres in lung → unable to detect growth of tumour
  
  • Then spreads to lymph nodes & liver

Question 6

TNM staging of tumours

Answer 6

1. tumour growth size
   
   • T1 = <3cm
   • T2 = >3cm
   • T3: any size in chest wall
   • T4: any size in mediastinum
2. Growth to nodes
   
   • N0 = none
   • N1 = Hilar nodes
   • N2 = Subcarinal nodes
   • N3 = neck
3. Metastasis

Question 7

Treatment of NSCLC

Answer 7

• Stage I & II →surgery/high dose radiotherapy
• IIIa → chemo-radiotherapy
• IIIb → Palliative chemo-radiotherapy
• IV → Palliative radio-therapy/chemo-therapy

Question 8

Chemotherapy of NSCLC

Answer 8

• Not as effective → not cure, just delays symptoms → ↑survival & quality of life
  
  • Gemcitubine & vinorelbine
    
    • Single drug for elderly/more frailer patients
  • Paclitaxel
  • Docetaxel (2nd line therapy)

Question 9

EGFR-TKi

Answer 9

• Gefitinib, Erlotinib
• Highly selective
• Orally available
• Inhibits EGFR-TK → prevents gene transcription/cell-cycle progression

Question 10

What use are drugs of pallitaion

Answer 10

• ↓bulk of cancer pushing on trachea → ↓cough
• Supplemental O2 & narcotics → for hypoxia & breathlessness
• Early use of palliative therapy → prolongs survival (may be > chemo)
  
  • Prognosis improves