Gut Microbiome Dysbiosis and Cancer: A Systematic Review on the Emerging Role of Probiotics in Oncology.
Source: PubMed, NCBI / U.S. National Library of Medicine
To evaluate the role of probiotic supplementation in cancer patients and its clinical effects. English-written clinical trials, pooled-, or meta-analyses of clinical trials assessing probiotic treatments in cancer patients. PubMed, Scopus, and Web of Science databases up to September 2025. Narrative synthesis of included studies, stratified by assessed outcomes. 3 clinical trials, 1 in vivo study followed by a clinical trial, 2 meta-analyses and 1 pooled analysis. Across chemotherapy settings, probiotic supplementation was associated with a reduction in clinically relevant diarrhea, with the most consistent signal for severe diarrhea and for selected subgroups (e.g., patients with colostomy during irinotecan-based therapy). Meta-analytic evidence also supported improvements in other gastrointestinal (GI) symptoms (nausea/vomiting, bloating, anorexia). In surgical oncology, perioperative probiotics/synbiotics were associated with faster GI functional recovery and favorable recovery-related markers in individual trials, while pooled randomized evidence in colorectal surgery indicated fewer postoperative infections and shorter length of stay; effects on anastomotic leak were inconsistent. Controlled clinical studies did not report probiotic-strain invasive infections, although rare serious events have been described in broader evidence. Heterogeneity in study designs, formulations, and outcome definitions; limited reporting of resource-utilization outcomes and adverse-event attr
Abstract
To evaluate the role of probiotic supplementation in cancer patients and its clinical effects. English-written clinical trials, pooled-, or meta-analyses of clinical trials assessing probiotic treatments in cancer patients. PubMed, Scopus, and Web of Science databases up to September 2025. Narrative synthesis of included studies, stratified by assessed outcomes. 3 clinical trials, 1 in vivo study followed by a clinical trial, 2 meta-analyses and 1 pooled analysis. Across chemotherapy settings, probiotic supplementation was associated with a reduction in clinically relevant diarrhea, with the most consistent signal for severe diarrhea and for selected subgroups (e.g., patients with colostomy during irinotecan-based therapy). Meta-analytic evidence also supported improvements in other gastrointestinal (GI) symptoms (nausea/vomiting, bloating, anorexia). In surgical oncology, perioperative probiotics/synbiotics were associated with faster GI functional recovery and favorable recovery-related markers in individual trials, while pooled randomized evidence in colorectal surgery indicated fewer postoperative infections and shorter length of stay; effects on anastomotic leak were inconsistent. Controlled clinical studies did not report probiotic-strain invasive infections, although rare serious events have been described in broader evidence. Heterogeneity in study designs, formulations, and outcome definitions; limited reporting of resource-utilization outcomes and adverse-event attribution; few large-scale trials; scarce direct oncologic efficacy endpoints. Probiotics appear to be a promising adjunct for supportive care in selected cancer pathways, particularly for GI toxicity and perioperative outcomes. Strain-defined, adequately powered trials with harmonized endpoints are needed to inform guideline-ready use.