A Prospective, Phase II Trial Using ctDNA to Initiate Post-operation Boost Therapy After Adjuvant Chemotherapy in TNBC

Inclusion Criteria:

* Patient is ≥ 18 years-old at the time of consent to participate this trial
* Stage II - III primary triple negative breast cancer patients(TNBC), TNBC is defined as ER \<=1%, PR \<=1%；HER2 receptor IHC=1, or IHC=2 and FISH negative.
* positive ctDNA after curative surgery and/or adjuvant chemotherapy
* ECOG 0-2
* If indicated, patient agree to receive adjuvant radiotherapy according to the institutional guidelines
* Patient receives adjuvant chemotherapy according to the NCCN guidelines
* Patient has available tumor tissue from the surgical specimen for next generation sequencing(NCS)
* Patient agrees to give blood samples for ctDNA tests every 3 months in 5 years

Exclusion Criteria:

* Patient has previously received any PD1/PDL1 blockage treatment
* Pregnant or breast-feeding (lactating) women or women who plan to become pregnant or breast-feed during the trial
* Patient with distant metastases of breast cancer beyond regional lymph nodes (stage IV according to AJCC 8th edition)
* Patient participates another interventional clinical trial
* Patient has a concurrent invasive malignancy or a prior invasive malignancy whose treatment was completed within 3 years before randomization
* Patient with autoimmune disease preventing the use of camrelizumab
* Patient has any other concurrent severe and/or uncontrolled medical condition that would, in the Investigator's judgment, cause unacceptable safety risks, contraindicate patient participation in the clinical trial or compromise compliance with the protocol