• Female or male patients 18 years of age or older.

• Histologically or cytologically confirmed breast cancer

• T1c N1-2 or T2-4 N0-2 early-stage disease

• ER/PR negative (ER/PR \<1%) or ER/PR low positive (1%≤ER/PR≤10%), and HER2 negative as per institutional and ASCO-CAP guidelines)

• Initiated the NAC with the first regimen of KN-522 regimen (i.e., pembrolizumab 200 mg Q3W, given with 4 cycles of paclitaxel + carboplatin).

• ECOG performance score of 0 or 1.

• The volumetric change of primary tumor = 0% or increase in volumetric size by US or MRI after completing the first part of the KN-522 regimen.

• Negative serum pregnancy test within 72 hours of receiving the first dose of the study medication for women of childbearing potential as per institutional guidelines. Postmenopausal women (defined as no menses for at least 1 year) and surgically sterilized women are not required to undergo pregnancy tests.

• Agreed with undergoing the image-guided core needle biopsy after completing the first part of neoadjuvant treatment regimen.

⁃ Subjects of childbearing potential should be willing to use effective birth control methods or be surgically sterile or abstain from heterosexual activity for the course of the study through at least 4 months after the last dose of the study drug. Subjects of childbearing potential are those who have not been surgically sterilized or have not been free from menses for \> 1 year. Effective methods of birth control include:

∙ Use hormonal birth control methods: pills, shots/injections, implants (placed under the skin by a health care provider), or patches (placed on the skin).

‣ Intrauterine devices (IUDs).

‣ Using 2 barrier methods (each partner must use 1 barrier method) with a spermicide. Males must use the male condom (latex or other synthetic material) with spermicide. Females must choose either a Diaphragm with spermicide, cervical cap with spermicide, or a sponge.

⁃ The patient must have adequate organ function as determined by the following laboratory values:

∙ Absolute neutrophil count\* ≥ 1,500 /μL

‣ Platelets\* ≥ 100,000 /μL

‣ Hemoglobin\* ≥ 9 g/dL

‣ Creatinine clearance \> 50 ml/min

‣ Total bilirubin ≤ 1.5 X ULN

‣ Alanine aminotransferase and aspartate aminotransferase \< 2.5 X ULN \*Hematologic counts above should be without transfusion or growth factor support within 2 weeks of study drug initiation.