My friend just finished her treatment for throat cancer. She could only get chemo & radiation, surgery was NOT an option. I don't recall her saying anything about the back pain but that radiation sure is wicked stuff!! She still has a very hard time eating due to the lack of saliva.
I just want to say it does seem like this will never end but it will and there is light at the end of the tunnel. Power of prayer really works.
Best of luck to you!