Hello JOHN1954 and welcome.  I am sorry your partner is so unwell.  You don't give a lot of information but it can happen that cancer can reappear in a secondary site.  You don't state the location of the primary cancer and I think you are saying the the lungs are now the site of a secondary cancer and you are are wondering whether your dad's throat is yet another such site?  The person to talk to about this is  the doctor who is treating your partner who can give better and reliable information than we here who are not medically trained.    I am sure you are going through a horrible time but it is always better to know what is happening.  If your partner has not given permission for you to be given his medical information perhaps he would not mind doing this now so you can be sure of getting the up-to-date information .  Annie