regarding frequency of testing, I think age and other attributes would give a doctor info for a game plan. But consider that the numbers bounced around for the recaf test are nothing compared to a more definitive test like an MRI, Cat Scan or colonoscopy. You could have weekly recaf tests for a year and still be cheaper than an annual catscan.

Not only that, but catscans give you far more radiation than a typical x-ray, thereby increasing your risk of other cancers if you get too many over the years. This might sound silly, but if recaf could be used more reliably than, say, the CEA for followup to cancer surgery, I expect doctors would be able to rule out a lot of adjuvant therapy (chemo and/or radiation), and avoid a lot of followup catscans.

I spoke to one guy who had colon cancer. He got regular CEA tests suggesting everything was fine, and yet a scan revealed raging metastatic tumors in his liver. That is why people also get scans, X-rays and so on in addition to CEA (or other blood tests depending on the type of cancer). Current blood tests are just not reliable enough.