Well I went to the ENT today, and he said he was sure it wasn't cancer, and no need for a biopsy. Said it would be "thicker" if it were cancer.

He prescribed me some steroid ointment and suggested I use a toothpaste without the ingredient sodium lauryl sulfate.

I go back to him in 3 weeks. Sure hope he's right. Wish I had more faith in him. Thanks for your info, I will let you know if it doesn't go away.