White Lesion on retromolar trigone.

I have developed a white patches in my mouth for 60 days , image attached herewith. Though it has no pain, no bleeding. Some day it increases & someday it is decreases (attached some images). Recently I have visited an ENT specialist, by just seeing he referred me to Dental Specialist, after checking Dentist advice me to remove the upper third molar as there is no place for it which impacted & caused this, on asking about healing time of this patch, my dentist told that it will not heal until unless wisdom teeth is removed.  Shall I be worried. Is it oral cancer or something like that. I am a non smoker, non-drinker & never chewed tobacco. 2. If this kind of lesion is present in any other site inside mouth? Available both side gum near wisdom teeth. 3. Is there any history of tooth brush trauma? No but there may be a chance of teeth biting at same position. If any medication should I try, I need a 2nd opinion.