Respiratory

Question 1

What is the most common lung cancer?

Answer 1

Metastasis

• bladder, breast, colon and prostate

Question 2

What is the most common primary lung cancer overall?

Answer 2

Adenocarcinoma

Question 3

Adenocarcinoma

• Location:
• Mutations:
• Clinical associtation:
• Stain:

Answer 3

• Location: Peripheral
• Mutations:
  
  • Activating mutations in KRAS, EGFR, and ALK
• Clinical associtation:
  
  • hypertrophic osteoarthropathy (clubbing)
• Stain: Mucin (+); glandular pattern

Question 4

What is the subtype of adenocarcinoma of the lung?

Answer 4

Bronchioalveolar subtype

• Grows along the alveolar septa ⇒ apparent “thickening” of alveolar walls
• CXR often shows hazy infiltrates similar to pneumonia
• Excellent prognosis

Question 5

• Which lung cancers are centrally located?
• How are they treated?
• What is their histology?

Answer 5

• Small cell (oat cell) and squamous cell
• Treated with chemotherapy
• Histology:
  
  • Small cell: Chromogranin A (+)
    
    • Kulchitsky cells (“blue” neuroendocrine cells)
  • Squamous cell: keratin pearls and intercellular bridges

Question 6

What lung cancers have endocrine associations?

Answer 6

1. Small cell (oat cell) carcinoma
   
   • ACTH (Cushing syndrome), SIADH or Antibodies against presynaptic Ca²⁺ channels (Lambert-Eaton myasthenic syndrome), Amplification of myc genes
2. Squamous cell carcinoma
   
   • Cavitation, Cigarettes, hyperCalcemia (PTHrP)
3. Large cell carcinoma
   
   • Can secrete ß-hCG
4. Bronchial carcinoid tumor
   
   • Symptoms are usually due to mass effect; occasionally carinoid syndrome (5-HT secretion ⇒ flushing, diarrhea and wheezing)

Question 7

What is the histology of large cell carcinoma of the lung?

Answer 7

pleomorphic giant cells

Question 8

What are the pneumoconioses?

Answer 8

1. Asbestosis
2. Berylliosis
3. Coal worker’s pneumoconiosis
4. Silicosis

Question 9

What areas of the lungs are affected by the different pneumoconioses?

Answer 9

• Lower lobes:
  
  • Asbestosis
• Upper lobes:
  
  • Berylliosis, coal worker’s pneumoconiosis, silicosis