My Mother Is 94 Years Old She Have Thyroid Problem.

My mother is 94 years old she have thyroid problem. She have been spitting a lot lately. She had a CT scan done 3 weeks ago. her results is her thyroid has enlarged. Not sure if she is choking when she is spitting. I wonder if it is uncomfortable for her to swallow her saliva. Her Dr. mention surgery if she ever get where she is choking. I need to know if it is to dangerious considering my mom age for her to have thyroid surgery'