what's options and cost for private cancer treatment in UK?

my mum has been diagnosed bowel cancer last week.  She lives in China and I have no siblings. I have been living in the UK for the last 20 years and have a good job. I hope at some stage I can bring my mum to the UK for further treatment. As she's chinese, I would think the medical bills will be huge paying everything private. does anyone know  how much it can cost or if any help could be available for my situation? I can think of options of going back to China, but think if she can come here, treatment here might be better for her. Thanks Jane