A. TNBC accounts for ~30% of all breast cancer cases B. TNBC is generally less aggressive than HER2+ disease C. TNBC is comprised of distinct molecular subtypes that are correlated with prognosis and may impact treatment D. TNBC is less common in individuals of African-American and Hispanic heritage

A. Tumor-infiltrating lymphocytes (TILs) are common in TNBC and are thought to be associated with improved prognosis and response to neoadjuvant therapy B. Tumor mutational burden (TMB) is a predictive biomarker of immunotherapy efficacy in breast cancer C. PD-1/PD-L1 expression is significantly higher in HR+ breast cancers vs TNBC D. Though mismatch repair (MMR) deficiency is thought to play a prominent role in TNBC, BRCA mutations are uncommon in TNBC

A. Response to checkpoint inhibitor monotherapy in mTNBC has been shown to be robust and clinically-meaningful B. The KEYNOTE-522 trial demonstrated that the addition of pembrolizumab to neoadjuvant chemo improves pCR rates C. No FDA approvals of checkpoint inhibitors have yet been rendered in TNBC D. In advanced disease, PD-L1 expression does not appear to significantly influence response to checkpoint inhibition

A. Start IV hydration, oral prednisone 1 mg/kg/day, and infliximab B. Admit BK to the hospital, start IV hydration and IV methylprednisolone 1.5 mg/kg/day, and consider addition of infliximab if no improvement within 24 hours C. Admit BK to the hospital, start IV hydration and IV methylprednisolone 1.5 mg/kg/day, and consider addition of infliximab if no improvement within 2 weeks D. Start oral prednisone 2 mg/kg/day and taper over 2 weeks