Hi Mayflower, I get Cankers all the time and I have never had them tested or is there such a test. They are ulcers and sometimes meds, teeth, or acidic foods can bring it on. When ever I am on Flagyl, almost guaranteed I get one, last week I got 2 at the same time, first time in over 30 years. Anyone know of such a test??? There are ways to help the pain when they do come but it crohns realated.