Grandma is in the 3rd stage of adenocarcinoma lung cancer.Help!

To the kind-hearted all who read it:
A week ago a tentative diagnosis showed that my grandma was in the third stage of adenocarcinoma lung cancer. Doctors said that it was not suitable for her to have a surgery or receive chemo-treatment and they would use gamma knife to kill the tumors. I don’t know to what extent can the disease be cured in that way and is there any other better method to save her life?
As she has been coughing and feeling a sense of depression in her chest and coughed up blood once, I’m really worried about her. Could anyone give some advice on the treatment and therapy? Thank you very much for your reply. I’m looking forward to it.
Sincerely Michelle
16,10,2009