Mets to the bone and liver- what to expect?

After a long wait (since April/08) we finally found out what stage my 53 year old, mentally challenged brother is at. He had a Pet Scan on Monday and apparently there are several metastisized lesions on his liver and a tumor on his spine (he has been suffering from back pain for the last six weeks). Because I didn't want him to be more frightened than he already is, I did not ask the doctor what I should expect to happen as this cancer spreads and progresses because he was sitting right there. Now the doctor has left for holidays so I can't ask until he returns. In the last month, he has lost about 10 pounds, sleeps more often and has generally slowed down. He has a slight cough and enough back pain to make him uncomfortable but not keep him from walking. Up until last month, he was in excellent health and walked up steep hills continually for several hours a day. They will be giving him 5 days of radiation and some chemo to try and help eliviate some of the pain, but it is pallitive and not curative. He was told that this cancer has spread and cannot be cured, but I don't think he knows that he probably will die from it. He is so innocent and trusting, and I see no point in telling him anymore than is necessary. But I would like to know what to expect, so I can prepare when necessary. What will happen as the cancer grows in his liver and in his spine. How fast does it grow? Should I be making any plans for the near future?