Cancer Shedding: Those who want to be screened for colon cancer but don't want to have an endoscopic procedure to do it, currently have to have their stools checked for blood. The drawback to that is that there's a high rate of false positives. But researchers are looking for ways to detect shedding cancer cells in the stool. There have already been some tests that depend on genetic identificaiton of cancer cells. Here's one that identifies a chemical produced by tumors. If it pans out, it could lead to fewer needless colonoscopies.