question: My dentist referred me to a pathologist because i have a white ulcer like lesion on one side of my gums. Is this something that i should worry such as cancer or can it be a simple canker sore. i notice it when i felt a bit of discomfort such as like having something in between you teeth and cheeks.  I brushed it and irritated the area and it bleed. no pain just irritation when i use salt and water or mouth wash.  not a smoker or tobacco user. please advised. thank you