Coeliac Disease and Chemotherapy

Hi, my mum (post menopause age 68) has recently had surgery for stage 3 locally advanced breast cancer (metastasised into 4 lymph nodes.. hormone positive receptors) and has been recommended to undergo chemo > radiation > immunotherapy. 

She is healthy but has been navigating highly sensitive coeliac disease for many years. One of the factors in considering chemo is concerns over gut health and chemos effect on a person with coeliac disease (small intestine). 

Has anyone here with coeliac disease had any experience with chemo?