Sounds to me like it must be very small which is always a good thing! The earlier it is found the easier it will be to treat.
At a comprehensive cancer center they will use a team based approach. All the specialists get together and discuss each case individually. They will then come up with a treatment plan to present to the patient. Since you mentioned your mother being referred to an ENT it sounds like she is not being treated at a CCC. I recommend at least getting a second opinion at a CCC. They are the best places to get treated for oral cancer.
Cancer Center List Wishing you both all the best with everything.