Lisa,
Our story is very similar to yours. My father is 69 and extremely fit. We were shocked to hear Mesothelioma III stage.
My dad is taking Altima (chemo). He has had 3 treatments, one every 3 weeks, and his pain has been reduced greatly. You could see the tumor on his back (had grown through his ribs) and it is noticably smaller. He will go back for more scans after the next round and they will give him a break from the chemo. We don't know what will be done from there or whats available. It seems hard to find information from folks about Meso. Maybe because its rare.
If your mother is given Altima I can tell you about some of the side effects as I'm sure many here can. After the first round of chemo my dad didn't feel good, but other than that it was okay. Since further treatments, he has developed sores in his mouth and a terrible rash. The rash doesn't itch, just looks horrible (big red blothes). His appetite is not good. That seems to be a problem not only with the chemo but with this cancer. Food does not taste right to him. He says things taste really sweet alot of the time. He has a hard time concentrating and is REALLY cranky. He also got shingles. We caught them the first day which was a real blessing. It seems if they are treated within the first 48 hours you are more likely to stop them in their tracks.
One thing to be aware of when your mother is taking chemo is that it's easy to get infection. My dad was moving firewood (slowly one piece at a time)finished and thought no more of it. The next day where the wood had roughed his skin there were red dots. He immediately started a round of antibiotics.
I wish I knew more. As we proceed I'll pass on what I find out.
If you don't mind giving your Mom's first name I'd like to pray for her and you. I know now how difficult it is to hear this kind of news.
Lisa from Ohio