Non-CEA Blood Test for Metatastic Colon Cancer

[sean]

Has anyone used this test or know about it? I am pretty sure this was the test recommended to me by an oncologist if I decided against chemo as additional safeguard to see if there was metatastic disease lurking. I don't know if it catches it before a CT would or not or why it hasn't been approved by insurance companies yet or even if all tumors have the marker.

http://www.tdtinc.com/t_prod_blood.html

[betsydoglover]

This is interesting - I am suspicious - as always - regarding these things, but I will ask my onc about this in July. They don't sound like "quacks", but it is also strange that insurance most likely won't pay. CEA is fraught with difficulties - wish I had some real info with respect to this test as compared to CEA. (My CEA sucks as a marker for me!)

Take care,
Betsy

[JAZZToo]

I've heard of the GCC test. The problem with it, is you may have circulating colon cancer cells in your blood stream that would never colonize and become a growing colon cancer met. So there would be a positive test, but it doesn't mean that there is an actively growing cancer. Its the same thing with the PSA test. Many men have very tiny prostate cancers that never progress. But how do you tell the duds from the ones that will become active? EVery day our immune system destroys cells that if left to live could cause problems. So a few floating colon cancer cells might very well be destroyed before they could settle in somewhere and sprout a met. Besides, not all cancer cells are capable of rooting and becoming mets.

Jazz

[ray]

I'm enrolled in a clinical trial for the GCC test. I've been having blood drawn for the past two years and will continue for one more. Guanylyl Cyclase C is a protein normally found in intestinal mucosal cells as well as colorectal cancer cells no matter where located. The presence of GCC in the blood would indicate free floating CRC cells.

The problem is as Jazz mentioned, it's far from certain that free floating CC cells will become a tumor.

Data from the study I'm in will help determine just how many do become mets and if the test can be used as a basis to begin treatment or just increased surveillance.

[sean]

Thanks everyone for the good info. My thinking is that about a year or two after chemo I'll probably pony up for the test just to see if there is any cc floating around. Hopefully the clinical trials will have some preliminary results by then.