CEA lower in obese patients as much as 20% (false readings)

[dianetavegia]

I saw this post on another forum and it reminded me of something we'd discussed earlier about CEA and dehydration. I'd also seen a report that said normal CEA values (it might be in this article) are slightly higher for those over 50 than under 50 and rises again for those over 70. Interesting! This 2010 article suggests doctors should take these things into consideration when using CEA during follow ups.

http://cebp.aacrjournals.org/content/19/10/2461.full

Prior studies suggest that obesity is inversely associated with tumor marker concentration and may reduce diagnostic precision. This study was undertaken to evaluate the association between body mass index (BMI) and serum carcinoembryonic antigen (CEA) concentrations in colorectal cancer patients.

Obesity might be one of the factors that affect CEA value, leading to loss of sensitivity and diagnostic accuracy in the CEA test. The BMI status of patients should be taken into account during assessment of serum CEA during the surveillance of colorectal cancer.

Based on the above, we hypothesized that the diagnostic precision of the CEA test was affected by body mass index (BMI) status. This theory was examined in the context of colon cancer, and we explored whether large plasma volumes in obese patients were associated with lower CEA concentrations.

Patients with BMI of ≥27.5 displayed 15% to 20% lower mean CEA concentrations relative to normal-weight patients. Based on this theoretical formula, the observed CEA concentration of 7.0 ng/mL in normal-weight patients corresponded to 6.1 ng/mL in obese patients.

[very worried husband]

BY looking at my wife's CEA, it does make sense

[dianetavegia]

Goes to show that we worry way too much about little blips on that reading!