Gita
First let me say how sorry I am for your sisters news. I took my mother-in-law last thursday and she was given basically the same news, no more treatment recommended, probably last a year! When they take your hope away its so very hard. If your sister is like us she is going through all kinds of emotions right now. I hope you are able to talk to her about what she wants, how she wishes to spend what time is left. It really is the most important thing no matter what any one else thinks or says.
I hope they have a good pain management centre where you are, we do at Princess Margaret in Toronto and I can phone them anytime with a question. You should be very blunt with the doctors and ask what to expect. Of course everyone is different but you need to know what there plans are for handling her pain and what the side effects are going to be. Apparently there are meds that don't make you sleepy all the time, I have yet to research that, its on my to do list. But its important that she gets to spend some quality time with her family. Whatever happens, just make sure its what your sister wants, its sounds like she has had enough and doesnt wish to fight anymore, and if thats her wish then so be it. Just remember how good it is for her to have you there when she most needs you.
Take care

Karen