The Potential Effect of Oral Microbiota in the Prediction of Mucositis During Radiotherapy for Nasopharyngeal Carcinoma.

•The oral microbiota of NPC patients are different to that of healthy persons.•The biodiversity of oral microbiota changed significantly as mucositis progressed during radiotherapy.•Oral microbiota represents a potential strategy for predicting the aggravation of severe mucositis during radiotherapy.