RecruitingPhase 2Drug trialPET Dynamics to Response-Adapted Neoadjuvant Therapy in TNBCEligible patients with stage 2 and 3 triple negative breast cancer will be treated with 4 cycles of neoadjuvant paclitaxel/carboplatin/pembrolizumab. A PET scan will be performed at baseline and after 1 cycle of therapy. A breast MRI will be performed after treatment completion. Patients with complete clinical response will proceed to surgery. Patients with clinical residual disease will complete neoadjuvant rescue with 4 cycles of doxorubicin/cyclophosphamide prior to surgery. If residual disease identified after surgery, adjuvant therapy to be determined by the treating oncologist (may include doxorubicin/cyclophosphamide/pembrolizumab, capecitabine etc).