When someone is going through a hardship this severe, it's probably time to put aside your own way of looking at the world and do, for a time, whatever it is that brings you closer to that person. Your belief or non-belief does not outweigh your relationship with your wife.

Let the religious folks be the ones who are unfortunately hung up on such notions.

When faced with a life threatening illness prayer seems to be the only comfort left....we all know its a waste of time but dying people do find solace....If she asks for prayers then give her some...it won't hurt but will go a long way in making her feel better....even if it is temporary.!

I can identify. Tell her you will pray but in your own way. Say that you have to do it this way because you want it to come from the heart. Express your love for her as you tell her this.

I can understand her and you, but how about you put your believes to a side. Tell her that you will pray but that as you know you don't believe. Do it for her.

Is transplant an option? Only need a part of one.

This is a bit of a stretch perhaps, maybe just a rationalization but I tend to think there is a beneficial effect to/from prayer. One theory goes something like this. Our brains function though electrochemical processes. Prayer can be seen as a form of focusing the energy produced by our thoughts to create an action. At the level of the world we can perceive that energy may be virtually undetectable but on the quantum level it could be possible for that thought energy to act like a snowball rolling downhill. With enough individuals focusing on the same result,enough energy could cause a cascade that on the cellular level might tip the balance toward helping a body fight an invading disease. Think of it as the butterfly effect only working with a body's ability to fight disease.

I can very much relate. My mother was not very religious, but when my dad developed cancer, she became more so. He unfortunately died, and all our relatives engaged in further prayer, and even called a priest to tell what were nothing more than superstitious stories. As a hard athiest I found that people did not appreciate logic, rather, they wanted to believe that a miracle will be upon them. In your situation, I would give support to your wife, even if it means prayer, if for no other reason than the fact that the placebo effect on your wife may improve her mental well-being.

You should pray with your wife and tell her you are doing it for her. You can still be perfectly honest about your own beliefs, but that is not the focus here. If it starts stressing her out drop the subject. I hope she gets better.