I am posting from a remote computer since my system is down ( I am moving all this week and have no computer access) Since your husband had mets to the lymph system, there is always the possibility that some cancer cells migrated to a distant location at that point. It would be prudent to do a PET test to take an overall look at things, and to be sure that the most likely location for metastasis, the lungs and the rest of the aero digestive tract, are looked at with a scanning technology as well. In his weakend post treatment state, he is a candidate for numerous types of infections ( high temperature). If he has not been eatng well and his immune system is compromized by poor nutrition and the treatments this could be a cause. But please have them check out possible metastasis sites, don't panic, don't expect the worst, just be sure that you have looked at everything.