I am sorry to hear that your husband seems to have developed further tumors. From your description the cancer is in his neck? Not in the throat?
I am having trouble with what you refer to as swallowing issues, this points to inflammation inside his throat. I realise only too well that getting to the start point of exactly where a cancer may be coming from and what area it is affecting and could affect later. The PET Scan should put most of this to rest and the biopsy should then be bale to tell you exactly what type of tumor it is. I had a further PET myself last week, it only showed what inflamation I had from Radiation now 3 full years ago.
Today I was supposed to attend a meeting where all the oncologists both Chemo and radiation, get together with the all the ENT specialists to discuss and go over all available information on just where I and a lot of others are at. My radiation oncologist, put a stop to my attendance and said it would be a waste of my time? What I have is a very bad Larynx and Vocal chord area, talk about swallowing issues, to me it is just how much I want to chock while eating or drinking. Sometimes I just give up both just to get a breath in. Surgery, well that should be a choice your and yourself need to look at closely. Just what are they hoping to achieve and what quality of life will your husband have afterwards. i don't know his age, this can be something you need to take into account. My ENT want to remove my Larynx they have done for the past 3 years told me it needs to come out and i can sort of make noises through the hole in my Throat. Well that is not for me, I am 75 years of age and I don't see any real outcome benefit. Lousy life one way or the other, one with or without a Larynx. Scariest thing for anyone is the cancer affecting the Lymph nodes, mine did but Radiation seems to have got that. You need to ask if his Lymph nodes are affected. If he can't have further radiation or Chemo what is his prognosis after surgery? So many questions, I hope I have at least pointed out some of the areas you need to look at, I don't know just how bad your husbands case is, what stage the cancer is 1-4. His general health and weight, all are so important.
My real hope is he is able to make a full recovery, so many do as those surgeons know exactly what they are doing and generally do it so well. Good luck, if you need further assistance, with anything there are so many on here with some great advice.