Difficulty accruing subjects the study accrual was closed

Breast cancer is the most common cause of cancer death in women. Adjuvant chemotherapy significantly reduces the risk of recurrence of high-risk breast cancer. However, about 30% of patients still have distant metastasis or local recurrence after chemotherapy. Moreover, 60% of patients had 3-4 degrees of adverse drug reactions during chemotherapy.

The purpose of the study is to investigate relationship between gut microbiome and adjuvant chemotherapy in early breast cancer patients.

Breast cancer is the most common cause of cancer death in women. Adjuvant chemotherapy significantly reduces the risk of recurrence of high-risk breast cancer. However, about 30% of patients still have distant metastasis or local recurrence after chemotherapy. Moreover, 60% of patients had 3-4 degrees of adverse drug reactions during chemotherapy.

The human gut microbiota have been considered the most important microecosystem living in symbiosis with the body. It is identified as a crucial determinant in cancer occurrence and development . Besides, Gut microbial alterations may influence the therapy efficacy and adverse drug event.

We collect the fresh tail stool sample 24h before adjuvant chemotherapy and 24h after adjuvant chemotherapy then the composition of intestinal microbiota and subsequent short-term alterations are analysed by 16srRNA sequencing.The purpose of the study is to investigate relationship between gut microbiome and adjuvant chemotherapy in early breast cancer patients.

Inclusion Criteria:

• Histologically diagnosed stage I-III breast cancer;
• Plan to receive adjuvant chemotherapy in our hospital;
• Sign the informed consent;
• Good compliance and willing to follow up.

Exclusion Criteria:

• Those who have started receiving adjuvant chemotherapy;
• Chemotherapy contraindications;

early breast cancer patients ready to receive adjuvant chemotherapy.