I found a test called a CEA that is used as a tumor marker. Here's a little of the information about it. I have also posted the website so you can check it out.
How is it used?
CEA is most useful to monitor treatment of cancer patients. It is used with patients who have had surgery to measure response to therapy and to monitor whether the disease is recurring. A blood test for CEA is often used as a tumor marker. Physicians can use CEA results to determine the stage and extent of disease and the outlook in patients with cancer, especially gastrointestinal (GI) and, in particular, colorectal cancer. CEA is also used as a marker for other forms of cancer. It has been found helpful in monitoring patients with cancer of the rectum, lung, breast, liver, pancreas, stomach, and ovary. Not all cancers produce CEA; therefore, the CEA test is not used for screening the general population.
http://www.labtestsonline.org/understanding/analytes/cea/tes
I do have some encouraging news, though. Daddy had his 3rd chemo treatment today and was able to swallow a few sips of water this afternoon. This is the first time anything has gone down in months!