Boyfriend mouth cancer from tobacco catagious?

No, it isn't: His cancerous lesion cannot be spread to you. I hope that he is treating the situation and that he will be ok...

Not contagious: But requires immediate treatment. Your boyfriend should be under the care of both an oral surgeon and an oncologist. Treatment cannot be put off even a short while. Make sure he follows the instructions he is given to the letter.

No: No. See oral surgeon or ENT doc if you have any of these symptoms: Persistent mouth sore, persistent mouth pain, a lump or thickening in the cheek, a white/red patch on the gums, tongue, tonsil, or lining of the mouth, a sore throat, hoarseness or feeling that something is caught in the throat that does not go away, difficulty swallowing/chewing.