Hi, Wayne. I'm so sorry to hear your mother's disease.
My father-in-low passed away from stomach cancer fifteen years ago and my wife and son inherit his costitution. She suffered from breast cancer to lose one of them several years ago. This disease is familiar to my family and always my great concern because I never want my son too to suffer from it in the future.
The multiple myeloma is, however, survival rate is high though no cancer is easy to treat.
I have checked how other patients do/did in our country.
A woman of 31 suffered it in 2004 and, after bone marrow transplantation treatment, came back to the society to work in 2007.
She keeps diary on her blog to confirm herself she is still OK now.
On her recent blog last month, she writes "No drugs for five days. I'm happy to sleep with no drugs."
Through Google translation -
Translated version of http://blogs.yahoo.co.jp/atsuko3sanbasi/folder/1218894.html
Please never be discouraged by this disease and obey your doctor.
Your mother will be fine step by step.
Shinpachi