Thanks for taking the time to reply PV123 ... the surgeon said the cysts are small and 'pre-cancerous' but not cancer. A bit like polyps in the bowel. They need to be watched.
The oncologist suggested the 6 monthly blood tests as I had lobular breast cancer which can spread around the body. I'm very glad I'm having them.
Yes the colonoscopy/endoscopy will be revealing as the surgeon said there might be something there which has pushed the readings up. Apparently the Ca19.9 is a reading for the pancreas, but other situations in the gut can push levels up. Or it can be nothing in particular that shows up at all.
And yes, this sort of thing pushes the anxiety levels up, that's for sure!
Thanks again