Diet-drive Gut Microbiome and Outcome in Patients With Early-stage Triple-negative Breast Cancer Undergoing Neoadjuvant Chemotherapy and Immunotherapy.

The current standard of care for patients with early disease triple-negative breast cancer is neoadjuvant chemotherapy. The addition of the immune checkpoint inhibitor (ICI) to this the NACT treatment regimen has recently been shown to substantially improve the outcome of this patient population. Several translational studies have suggested the potential influence of the gut microbiome in modulating the efficacy of ICI-based therapies. In addition to the influence on response to ICI, several studies also suggest a strong association between the gut microbiome and side effects with ICI therapy.

The aim of this prospective longitudinal study is to investigate the complex interactions between the gut microbiome, the tumour biology of early-stage triple negative breast cancer, the efficacy and tolerability of neoadjuvant chemotherapy (NACT) followed by immune checkpoint inhibitors, including the possible impact on the cognitive function and the long-term outcome. A specific focus will be to study the association of the gut microbiome and the risk of breast cancer recurrence in the high-risk group of patients with residual disease after NACT. The study will furthermore assess dynamic changes in both the gut microbiome and the tumour biology, and their association with long-term outcome. Furthermore, the association of nutritional input and the gut microbiome will be studied. Results of this trial might be the basis for future interventional studies that might stratify treatment modalities based on the gut microbiome or attempt to modulate treatment outcomes through targeting the gut microbiome.

At least 200 patients undergoing neoadjuvant chemotherapy plus immunotherapy and at least 100 patients undergoing neoadjuvant chemotherapy alone will be recruited into the study.

The study poses very little risk for research participants; blood samples and faecal samples are routinely performed in hospitals.

Informed consent will be obtained prior to the participants undergoing procedures that are specifically for the purposes of the study and our outside standard, routine care at participating sites. Ample time will be given for consideration by the patient before taking part. Written informed consent will only be obtained from those who the Investigator feels assured have understood the implications of participation in the study.

• To correlate microbiome findings with characteristics of CTCAE [Срок оценки: Through the study completion, an average of 5 years.]
• To correlate the gut microbiome findings with immune-phenotype of the tumour. [Срок оценки: Through the study completion, an average of 5 years]
• To correlate the gut microbiome findings with nutritional input. [Срок оценки: Through the study completion, an average of 5 years]
• To correlate the gut microbiome findings with cognitive function. [Срок оценки: Through the study completion, an average of 5 years]