My mother's doctor said that her tongue cancer was probably cause by chronic irritation too. My mother doesn't smoke nor drink. The doctor only notice that her left molar was extremely sharp, and my mother always hurt her tongue by biting into it.

When the lump on the underside of her tongue first appear, she thought that she must have bite into it again. And she used the evil mouthwash hoping that it will help with the healing, but after a few weeks, it's clear that the lump wouldn't go away on its own. And she started to have pain in the ear, and she just think that since she has DM, the wound might take a little bit longer to heal.

The ENT doc who dx her said that the cancer was caused by chronic irritation. While she can effectively repair the wound from biting when she was young, after 60 years of biting, something simply went wrong this time round.