Nonsmokers: <3 ng/mL; SI units <3 ng/L
Smokers: <5 ng/mL; SI units <5 ng/L
. Red-top or lavender-top tube, depending on lab.
■ Used to monitor treatment response and possible recurrence
of breast, colon, or pancreatic cancer.
■ Not a screening test since CEA can be elevated in benign
diseases and smokers.
■ Heparin use interferes with results. Hold for 2 days prior to
test.
