My advice is definitely a second opinion. His cancer should be treated with surgery first. They can rebuild his tongue and this would be the best way to knock the cancer on it's butt. Plus surprisingly it's easier to recover from than radiation. With three nodes involved I would anticipate a date with rads and chemo too. The reason I am saying surgery would be the best option is that unless it is HPV related cancer, rads and chemo alone doesn't always kill the tumor. This is why the guidelines state for this type of cancer the first line of defense is surgery - followed by rads and chemo for any clean up. If there are other reasons to avoid surgery (health reasons) then I understand. If not - do get a second opinion ( I think you said you were at Upenn) at a CCC. Hugs and best of luck.