Stage 4 Liver cancer , how ill is my Dad?

My dad is the best Dad in the whole world and I love so very much and I need to know a few amswers to know how poorly he really is. My Dad is 79 years old although he is this old he is really active (not as much now though , although he does try)He had gallstones and was in lots of pain and was admitted to hospital because he could not bear the pain . After several attempts to remove the stones they decided to remove the gallbladder. Once they removed the gallbladder they found that he had gallbladder cancer . I know gallbladder cancer is very rare . After they found out this they decided to dio a scan where they discovered something on his liver and nodules on his lungs, we have just got the results back from the liver biopsy and it is stage 4 liver cancer , the specialist at Hinchingbrooke has told us that on his notes they have said to weak for surgery but are asking for a second opionion. I really need to know how bad this is as my Dad is so special to me and I love him so much.