For patients with large operable and locally advanced breast cancer, primary systemic chemotherapy (PST) is currently the standard of care. Primary systemic chemotherapy has been shown to be equivalent to adjuvant chemotherapy in terms of overall survival (OS) and relapse-free survival (RFS),
1,2 and use of PST also increases the rates of breast conservation surgery. Primary systemic chemotherapy has an additional advantage in that it allows response to be assessed clinically in vivo throughout treatment and pathologically after surgery. Several studies have shown that patients treated with PST who achieve a pathologic complete response (pCR) in the breast and axilla have superior long-term outcomes.
2-4