TNBC Gut Microbiota During Neoadjuvant Treatment

The gut microbiome is made up of the microbes (such as bacteria, viruses, and other organisms too small to see with the naked eye) that live in the digestive tract and has been shown to be important in metabolizing food, extracting vitamins and nutrients from food, and maintaining a healthy gut lining. The gut microbiome plays an important role in overall health and has been shown to dynamically change in response to early-stage triple-negative breast cancer-directed therapies, which in turn has been associated with worse outcomes. As the gut microbiome can be further modulated with dietary changes during cancer treatment, it is an ideal potential modifiable risk factor in cancer patients. However, due to multiple confounding factors such as dietary intake, mood, and activity, its utility as part of the oncologic clinical assessment remains unclear. In this prospective randomized controlled study, the investigators propose to recruit up to 30 early-stage TNBC patients to randomize to a personalized nutritional intervention of a high-fiber diet coached by a registered dietician versus educational handout alone during neoadjuvant treatment. The investigators propose to study the gut microbiota through stool sample analysis among early-stage triple-negative breast cancer patients undergoing neoadjuvant (i.e. before surgery) chemotherapy +/- immunotherapy. The investigators will also study how the gut microbiota can be further modulated with a high-fiber diet, and the investigators hypothesize that a high-fiber diet may play a protective role in preserving gut microbial diversity. As part of the nutritional intervention, the investigators propose to administer nutritional counseling with a registered dietitian (RD) to increase fiber intake and tracking performance status, activity, and mood during neoadjuvant treatment. Finally, the investigators propose to survey participants after study completion through one-on-one interviews to determine whether participants experienced improved overall patient satisfaction in supportive care during their treatment.

NCT Number	NCT06610097
Lead Sponsor	Scripps Health Collaborators: San Diego State University, The Scripps Research Institute
Conditions	Breast Cancer, Triple Negative Breast Cancer, Early Stage Triple-Negative Breast Carcinoma
Start Date	2025-04-10
Primary Completion	2026-08-10 (estimated)
Study Completion	2026-08-10 (estimated)
Updated on ClinicalTrials.gov	2026-08-12