A new randomized, double-blind, placebo-controlled clinical trial has investigated the effects of synbiotic supplementation on reducing chemotherapy-induced side effects in women with breast cancer. The study was conducted at Firuzgar General Hospital in Tehran, Iran between April 2021 and April 2022. Funding was provided by Iran University of Medical Sciences. The results were published in September 2023 in the journal BMC Complementary Medicine and Therapies.
The purpose of the study was to evaluate whether synbiotics (a combination of probiotics and prebiotics) could safely and effectively reduce common chemotherapy side effects like nausea, vomiting, fatigue, and gastrointestinal issues in breast cancer patients. A total of 67 women with breast cancer undergoing chemotherapy were included in the final analysis.
To be eligible, participants had to be at least 18 years old with a recent definitive diagnosis of non-metastatic breast cancer. They were required to be undergoing neoadjuvant or adjuvant chemotherapy with Adriamycin and Cyclophosphamide, with at least one previous chemotherapy session completed. Exclusion criteria included chronic diseases, gastrointestinal diseases predating cancer, recent probiotic/prebiotic use, history of other cancers, and recent antibiotic use.
The 67 participants were randomized to receive either synbiotic capsules (n=34) or placebo capsules (n=33) twice daily for 8 weeks. The synbiotic supplement contained 12 probiotic strains and fructooligosaccharides as a prebiotic. Baseline characteristics were similar between the two groups, with a mean age of 53.6 years in the synbiotic group and 51.0 years in the placebo group.
The primary outcomes were changes in the severity or experience of chemotherapy complications, assessed using validated questionnaires at baseline, 4 weeks, and 8 weeks. Secondary outcomes included anthropometric measurements and dietary intake.
After 8 weeks, the synbiotic group showed significant improvements compared to placebo in several key areas:
- Defecation quality improved significantly (p=0.005), with complete resolution of diarrhea in all affected patients and 92.8% improvement in constipation.
- Nausea/vomiting (p=0.015) and anorexia (p<0.001) decreased significantly compared to baseline, though not statistically significant versus placebo.
- Energy intake increased significantly in the synbiotic group but decreased in the placebo group.
No significant between-group differences were observed for pain, sleep quality, mental status, or anthropometric measurements. Importantly, no adverse effects were reported from synbiotic supplementation.
The study had some limitations, including a relatively small sample size and short follow-up period. The COVID-19 pandemic also created challenges in patient recruitment. Additionally, the presence of many potential confounding variables made it difficult to analyze some outcomes separately.
Nevertheless, the authors concluded that 8 weeks of synbiotic supplementation appears to be a safe and promising approach for reducing some chemotherapy-induced side effects in breast cancer patients, particularly abnormal defecation and fatigue. They suggest synbiotics may also help ameliorate nausea, vomiting, anorexia and weight loss, though larger studies are needed to confirm these effects.
The potential clinical impacts of these findings are significant. Chemotherapy side effects can severely impact quality of life and sometimes lead to treatment interruptions. Safe, low-cost interventions like synbiotics that can reduce these side effects could help improve treatment adherence and outcomes. However, the authors emphasize that more research is needed to establish optimal protocols for synbiotic use in cancer patients before clinical recommendations can be made.
This study adds to a growing body of research on the potential benefits of targeting the gut microbiome in cancer care. While promising, medical professionals should interpret these results cautiously given the study limitations. Larger, longer-term trials are warranted to further elucidate the role of synbiotics in managing chemotherapy side effects and potentially improving cancer treatment outcomes.
References
Khazaei Y, Basi A, Fernandez ML, Foudazi H, Bagherzadeh R, Shidfar F. The effects of synbiotics supplementation on reducing chemotherapy-induced side effects in women with breast cancer: a randomized placebo-controlled double-blind clinical trial. BMC Complement Med Ther. 2023;23(1):339. Published 2023 Sep 26. doi:10.1186/s12906-023-04165-8
