The Gut Microbiome and Gastrointestinal Toxicities in Pelvic Radiation Therapy: A Clinical Review

Byeongsang Oh; Thomas Eade; Gillian Lamoury; Susan Carroll; Marita Morgia; Andrew Kneebone; George Hruby; Mark Stevens; Frances Boyle; Stephen Clarke; Brian Corless; Mark Molloy; David Rosenthal; Michael Back

doi:10.3390/cancers13102353

The Gut Microbiome and Gastrointestinal Toxicities in Pelvic Radiation Therapy: A Clinical Review

Cancers (Basel). 2021 May 13;13(10):2353. doi: 10.3390/cancers13102353.

Authors

Byeongsang Oh^{1

2

3}, Thomas Eade^{1

2

3}, Gillian Lamoury^{1

2

3}, Susan Carroll^{1

2

3}, Marita Morgia^{1

2}, Andrew Kneebone^{1

2

3}, George Hruby^{1

2

3}, Mark Stevens^{1

2}, Frances Boyle^{2

3}, Stephen Clarke^{1

3}, Brian Corless¹, Mark Molloy⁴, David Rosenthal⁵, Michael Back^{1

2

3}

Affiliations

¹ Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, NSW 2065, Australia.
² The Mater Hospital, Sydney, NSW 2060, Australia.
³ Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia.
⁴ Bowel Cancer and Biomarker Laboratory, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2065, Australia.
⁵ Harvard Medical School, Boston, MA 02215, USA.

Abstract

Background: Gastrointestinal (GI) toxicities are common adverse effects of pelvic radiotherapy (RT). Several recent studies revealed that toxicity of RT is associated with dysbiosis of the gut microbiome.

Method: A literature search was conducted in electronic databases Medline, PubMed, and ScienceDirect, with search terms "microbiome and/or microbiota" and "radiotherapy (RT) and/or chemoradiation therapy (CRT)" and "cancer", and the relevant literature were selected for use in this article.

Results: Eight prospective cohort studies were selected for review with a total of 311 participants with a range of 15-134 participants within these studies. The selected studies were conducted in patients with gynaecological (n = 3), rectal (n = 2), or prostate cancers (n = 1), or patients with various types of malignancies (n = 2). Three studies reported that cancer patients had significantly lower alpha diversity compared with healthy controls. Seven studies found that lower alpha diversity and modulated gut microbiome were associated with GI toxicities during and after pelvic RT (n = 5) and CRT (n = 2), whereas one study found that beta diversity was related to a complete response following CRT. Two further studies reported that fatigue was associated with dysbiosis of the gut microbiome and low alpha diversity during and after RT, and with dysbiosis of the gut microbiome and diarrhoea, respectively.

Conclusion: Gut microbiome profiles are associated with GI toxicities and have the potential to predict RT/CRT-induced toxicities and quality of life (QoL) in patients undergoing those treatments. Further robust randomized controlled trials (RCTs) are required to elucidate the effect of gut microbiome profiles on RT-related adverse effects and responses to RT.

Keywords: cancer; chemoradiotherapy; gastrointestinal toxicities; gut microbiome; radiotherapy.

Publication types

Review