Hello. The most important thing is to try an alternative way to help your 媽媽. The reason is that your doctor already admitted that there is 沒有什麼可以做. It is difficult for any traditional doctors to admit that.
You can definitely try Chinese medicine. I'd also suggest you to try Naturopathy (自然療法) which is a natural way to help any sickness. Much of it is related to nutritions and habits. Please keep in mind that if it takes some time for the body to degrade, it would also take the body some time to recover. That is no magic cure for any diseases. But, at the very least, we don't want to make the situation worse.
Mental support for your 媽媽 is very important. It is always helpful to have a relatively positive mindset and believe that a relatively better future is coming.
There are some starting points here:
http://www.club-o.org/
http://www.drallanchan.com.hk/