ca.27.29 tumor marker

If the highest level of normal is considered to be <37, how high can the marker go before a person should start to be concerned?

[CCF-RN,MSN-rf]

Dear busterdawg:  There is controversy among breast experts as to whether the 27.29 tumor marker is a reliable tool.  Certainly, it should not be used as a screening tool.  In the case of following a person with breast cancer, absolute value may not be as important as a trend up or down.  In other words, if it keeps rising that may be more significant than whether it is 37 or 40.