Background:
Radiotherapy is a routine treatment for
pelvic cancer patients. While it had been proven effective, gastrointestinal side effects remain a concern, impairing the quality of life. A few studies focused on the effects of hyperbaric
oxygen (HBO) treatment to alleviate radiation-induced gastrointestinal complications. This meta-analysis aimed to critically review and summarize existing literature, assessing the effectiveness of HBO
therapy for the treatment of radiation-induced gastrointestinal side effects. Methods: Medical literature search was performed with PubMed, Cochrane Library, and EMBASE up to March 14, 2019. Literatures about HBO treatment upon patients undergoing
pelvic cancer (endometrial, cervix, rectum, or
prostate cancers)
radiotherapy were collected, and the effects of HBO treatment on
radiotherapy-induced gastrointestinal complications were evaluated. A random-effects model was used to calculate the pooled effect size. Subgroup analyses were performed to search for sources of heterogeneity. Publication bias was detected with Funnel plots and Egger's test. Results: Three different
radiotherapy-related gastrointestinal complications, including rectal
bleeding,
diarrhea, and
pain, were analyzed after screening. It was revealed that the improvement rates were considerable in rectal
bleeding (0.81, 95% CI: 0.74-0.89) and
diarrhea (0.75, 95% CI: 0.61-0.90) and slightly in
pain (0.58, 95% CI: 0.38-0.79). Subgroup analysis revealed factors that significantly influenced the heterogeneity of rectal
bleeding,
diarrhea, and
pain (evaluation criteria, follow-up time, and scoring system, respectively). No significant publication bias was detected. Conclusion: HBO treatment might have the potential to alleviate
radiotherapy-related gastrointestinal complications, including rectal
bleeding,
diarrhea, and
pain, but more data are needed for further conclusions. Other symptoms were not further analyzed, as the number of studies was insufficient. More large-scale and prospective studies are needed for better evaluation of HBO's therapeutic values.