Hello Jean.  First of all, I am so sorry to hear what your daughter in law is going through.  When cancer is this far advanced, it isn't unusual to get pain.  However, it can not be ruled out that the cancer could be spreading.  Unfortunately no-one on this forum can give you the answers you need.  Only your daughter in law's medical team can tell her exactly what is happening.  You say that your daughter in law has gone downhill very fast in just 4 weeks, and I have to tell you that this is not a good sign.  Please forgive me if I have been too honest with you, but I think that you would rather hear the truth with no sugar-coating wouldn't you?  Once again, so sorry for your awful situation.  My thoughts and prayers are with you..