Preoperative symbiotic supplementation modulates the intestinal microbiota of patients with colorectal cancer: Evidence from a randomized clinical trial.

Preoperative symbiotic supplementation significantly increased the relative abundance of the phylum Firmicutes, family Bacillaceae, and genus Blautia in stool samples collected after surgery.

• Differences were observed in stool samples collected at T2 (after surgery) in the symbiotic (S) group compared with the control (C) group.
• Statistical significance was established at P < 0.05 for all three taxa (Firmicutes, Bacillaceae, and Blautia).
• The trial enrolled 46 patients total, with 23 subjects in each group.
• Patients received two sachets (6 g each) of symbiotic or maltodextrin twice a day for 4–10 days prior to surgery.

In patients who developed infectious complications, the relative abundance of the phylum Proteobacteria was significantly lower in the symbiotic group compared with the control group.

• This finding was specific to the subgroup of patients who experienced infectious complications.
• The difference was statistically significant at P < 0.05.
• No differences were seen between the groups regarding overall clinical or infectious complications (P > 0.05).

Preoperative symbiotic supplementation increased butyrate production at both postoperative time points (T2 and T3), while acetate and propionate production were increased at T2.

• Higher butyrate production was found at T2 (after surgery) and T3 (before hospital discharge) in the S group.
• Acetate and propionate production were increased at T2 in the S group.
• All short-chain fatty acid differences were statistically significant at P < 0.05.
• Stool samples were collected at three time points: before treatment (T1), after surgery (T2), and before hospital discharge (T3).

The symbiotic group showed increased mucus production in tumor tissue compared with the control group.

• Mucus production was evaluated in tumor tissue fragments collected during surgery.
• The difference in mucus production was reported as P > 0.05, indicating the increase did not reach statistical significance.
• Normal tissue and tumor tissue fragments were both collected during surgery for evaluation.

No significant differences were observed between the symbiotic and control groups regarding clinical or infectious complications.

• The trial was a single-center, parallel, triple-masked, randomized clinical trial conducted at Federal University of Minas Gerais Hospital, Brazil.
• P > 0.05 for all clinical and infectious complication comparisons between groups.
• All patients underwent nutritional and anthropometric assessments, as well as food consumption, bowel function, and digestive complaint assessments during pre- and postoperative periods.

The study design involved adult patients with colorectal cancer randomized to receive symbiotic or maltodextrin supplementation preoperatively for 4–10 days.

• This was a single-center, parallel, triple-masked, randomized clinical trial (NCT04874883).
• Patients received two sachets (6 g each) of symbiotic or maltodextrin twice a day for 4–10 days prior to tumor resection surgery.
• A total of 46 patients were enrolled, with 23 subjects in each group.
• Intestinal microbiota diversity and short-chain fatty acids were assessed from stool samples at three time points.