The Dukes classification is the classic staging system for colorectal cancer. In Dukes stage A, the cancer is limited to the muscular mucosa and submucosa with a mean survival rate of 90%. In Dukes stage B1, the cancer extends into but not through the muscular mucosa, and in Dukes stage B2, the cancer extends through the muscle but does not involve the lymph nodes; the survival rate is between 60% and 75%. In Dukes stage C1, the cancer is contained within the bowel wall and involves the lymph nodes, whereas in Dukes stage C2, the cancer extends through the bowel wall and involves the lymph nodes. With 1 positive node, there is a 69% survival rate; with 6 or more positive nodes, the survival rate decreases to 27%. In Dukes stage D, the cancer has metastasized to the liver, bone, or lung, and the survival rate is 5% or less.2
- Dukes stage D.
2. Rudy DR, Zdon MJ. Update on colorectal cancer. Am Fam Physician 2000;61:1759-70, 1773-4.
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