- Stage II or III (Duke B1-C1) Colon Cancer monitoring
- Do not use to screen for Colon Cancer or other cancer
- Normal
- Non-smokers: <2.5 mg/ml
- Smokers: <5 ng/ml
- Increased
- Benign disease unlikely if >10 ng/ml
- Distant metastasis most likely if >100 ng/ml
- Not specific
- Seen in other adenocarcinoma (see below)
- Sensitivity varies by tumor stage and differentiation
- CEA not increased in poorly differentiated tumors
- Increased in <25% of Duke A or B stage Colon Cancer
- Increased in 50% with Duke C stage Colon Cancer
- Increased in 75% of Duke D stage Colon Cancer
- Repeat CEA level q2-3 months for 2 years