Bi-Directional interactions between microbiota and ionizing radiation in head and neck and pelvic radiotherapy–clinical relevance

Purpose: Rapid developments in high throughput screening technology for the detection and identification of the human microbiota have helped in understanding its influence on human health and disease. In the recent past, several seminal studies have demonstrated the influence of microbiota on outcomes of therapy-associated radiation exposure. In this review, we highlight the concepts related to the mechanisms by which radiation alters the microbiota composition linked with radiation-associated toxicity in head and neck and pelvic regions. We further discuss specific microbial changes that can be employed as a biomarker for radiation and tumor response. Conclusion: Knowledge of the influence of microbiota in radiation response and advances in microbiota manipulation techniques would help to design personalized treatment augmenting the efficacy of radiotherapy.