The survival rate of patients with pathological complete response (pCR) after neoadjuvant therapy was significantly better than that of patients with tumor residue, that is, non-pCR patients. Therefore, studies have confirmed that intensive adjuvant therapy for patients with non-pCR after neoadjuvant chemotherapy can further improve the survival of this population. Previous studies have given capecitabine treatment to such patients as standard. However, it is unknown whether capecitabine intensification still has the same status under the premise that most patients receive immunotherapy at the neoadjuvant stage; Whether there are differences in the efficacy and safety of capecitabine standard 6-8 cycle intensive regimen and capecitabine metronomic chemotherapy are practical problems encountered in clinical practice. This study explored the efficacy and safety of 6-8 cycles of full dose capecitabine intensive therapy compared with 1-year capecitabine metronomic chemotherapy in patients with T2 and above and/or lymph node positive early triple negative breast cancer who still had invasive tumor after neoadjuvant therapy.

Inclusion Criteria:

• 1) Patients with triple negative breast cancer diagnosed by biopsy in Peking University People's Hospital;
• 2) The clinical stages before treatment were T1-T4, N0-N3, M0;
• 3) Received treatment and operation in our hospital, and had hospitalization records;
• 4) Neoadjuvant chemotherapy is unlimited, and immunotherapy is allowed in neoadjuvant and/or adjuvant treatment;
• 5) Postoperative pathology confirmed the presence of residual invasive breast cancer in the breast and/or axillary lymph nodes;
• 6) Has signed and agreed to participate in the PKUPH breast disease cohort study.

Exclusion Criteria:

• 1) Lack of clinical and pathological data (such as imaging data and pathological data);
• 2) Patients with metastatic breast cancer or bilateral breast cancer;
• 3) Failure to perform radical surgery;
• 4) BRCA has pathogenic or possibly pathogenic mutations, and received intensive treatment with PARP inhibitors after operation

Triple negative patients, non-PCR after neoadjuvant therapy