Classification of stage of colorectal cancer using Duke system

The Dukes system of staging colorectal carcinoma has gained the most widespread recognition.

• A: tumour confined to the bowel wall
  • 97% 5 year survival
    
    
• B: tumour extends across the bowel wall
  • 80% 5 year survival
  • if locally-invasive, dramatically worse prognosis
    
    
• C: involvement of regional nodes
  • C1: only a few nodes are involved near the primary growth and the proximal nodes are free from metastases
    • approximately 60% 5 year survival
  • C2: proximal nodes are involved
    • approximately 30% 5 year survival
      
      
• D: distant metastases
  • less than 5% 5 year survival

It should be noted that this is an extended classification as Duke originally described only 3 classes A, B and C.

Other systems include:

• Kirklin's:
  • A: confined to submucosa
  • B1: confined to the bowel wall
  • B2: through the bowel wall
    
    
• Astler-Coller:
  • C1: nodal involvement primarily confined to bowel wall
  • C2: nodal involvement through the bowel wall