Efficacy of Modified Si Ni San in Post-Polypectomy Management and Its Impact on Gut Microbiota in Colorectal Polyp Patients

Study Purpose: This study aims to systematically analyze changes in the gut microbiota of colon polyp patients under different intervention models. It will evaluate the regulatory effects of modified Si-Ni-San on the composition, diversity, and potential functional characteristics of the gut microbiota. Additionally, the study seeks to identify key microbiota species associated with inflammation regulation and potential recurrence risk, providing theoretical support for microbiota-targeted intervention strategies. Methods: This is a single-center, prospective, exploratory, randomized controlled trial involving patients who have undergone colon polyp removal via colonoscopy. After resuming normal oral diet, patients will be randomly assigned to either the Traditional Chinese Medicine (TCM) intervention group or the control group. The control group will receive a combination of glutamine and probiotics, while the TCM intervention group will receive modified Si-Ni-San. Both groups will undergo a 4-week intervention period (with 4 treatment cycles of 7 days each). Clinical symptoms will be assessed before and 1 week after the intervention using a Traditional Chinese Medicine symptom scale. Blood and stool samples will be collected to measure serum IL-6 and TNF-α levels, and 16S rRNA gene sequencing will be performed on the stool microbiota. The study will compare changes in the gut microbiota composition and diversity at different time points and between the two groups. Differential microbiota will be identified through indicator species analysis and LEfSe, and effect sizes and 95% confidence intervals will be reported. Additionally, a random forest model will be built, and ROC curves will be used to evaluate key discriminative bacterial genera. Exploratory analysis of microbiota phenotypes and potential functions will be performed using BugBase and PICRUSt.