My mum in law has non small cell lung cancer with plural effusion. How much longer will she survive?

I was diagnosed March 26 2005 with stage 3 non small cell lung cancer. I went through 5 weeks, 5 days a week, of chemo and radiation, and then on June 29 of 2005 they removed my entire left lung. Then 3 more weeks of chemo. Since then, I go in for a scan every 5 months and to this day I am cancer free. At the time I was diagnosed, the doctors told me I had a 1-15 percent chance of surviving. I am beating the odds at this point! Also, in March of this year, I found out I was going to be a father, another thing they said could not happen because of all the chemo I had! Our baby is due in 2 days! Keep your head up high. I feel for all of you who have suffered and lost loved ones. My heart goes out to you. With that said, only god knows when the time will come. I wish you and your family the best.

Shawn, Anchorage Alaska

any estimate is just a guess.one never knows,sometimes a while and others not so long.
make it good now and don't act like you have a lot of time.

I'm really sorry to hear that mate, i lost my mum to lung cancer in January of this year, she had stage 4 Non small cell cancer.
She was diagnosed on November 28th 2006 and that was devastating, on December 11Th 2006 we found out it was terminal and they gave her between 1-2 months life expectancy.
she was to sick for chemo/Radio therapy and the cancer had spread to her breast, lymph nodes and her bowel.
She made it through Christmas 2006 and passed away at home on January 6Th 2007, 2 days before my birthday.
Mum was as tough as old boots and refused to give in to "this effing disease" (Her actual words) and tried to carry on as best she could, the day she was diagnosed she came home from the hospital got out the ironing board and just got on with it.
Just after new year she took a turn for the worst and i had to call the doctor out, she'd got an infection on her chest, the doctor gave her some antibiotics even though we both knew they wouldn't really help her in anyway, i just wanted something to try and ease her wheezing chest.
My heart really goes out to you and your family, i never thought in a million years I'd be on Yahoo writing about cancer, let alone how it had claimed my mum.
I couldn't answer your question honestly about how long you MIL has got, her doctor should be able to give you all the answers you need to know.
Once again im so sorry and i wish i could give your mil a big hug!
Take care
Jackie