Sorry, I meant to explain that. I'm a bit scatter brained right now. It's the tumor marker for pancreatic cancer. It's a substance produced by cancer cells, or by normal cells in response to cancer. You can think of it like looking at white blood cell counts to determine if someone has an infection. A high number isn't necessarily indicative of anything, but an upward trend is a sign that chemo isn't working and cancer is spreading.Prayers coming - but, what does that number mean?