I had biopsies of the tongue, but was not cancerous. Were you or are you a smoker, chew tobacco, any other risks types for cancer, such as alcohol? I would want to have an endoscopy of the aerodigestive tract to check for any other involvement, in addiction too, a full body PET/CT scan first. As mentioned, seek another opinion, prefably at a CCC. Personally, I don't like the watch and wait approach when there are positive margins or any cancer for that matter, which really can go anywhere. When they did a RND, surprisingly, cancer was found in my neck muscle. in another surgery, I had positive margins in the cervical neck, a different area, under different conditions than yours, but they had to go all out on me with surgery, rads, chemo again. Good luck.