Neoadjuvant or adjuvant chemotherapy in early breast cancer?

INTRODUCTION: The administration of chemotherapy before (neoadjuvant), rather than after surgery (adjuvant) in early breast cancer has been considered an optional strategy for patients with operable breast cancer. We reviewed this concept considering recent results in the field. AREAS COVERED: Herein, the authors cover neoadjuvant chemotherapy with or without biologics in triple-negative and HER2-positive operable breast cancer with a focus on rates of complete pathological remission (pCR) in the breast and axilla. The impact of the CREATE X and KATERINE randomized clinical trials of post-surgical treatments in patients with residual disease after neoadjuvant chemotherapy is also discussed. EXPERT OPINION: The CREATE X and KATERINE clinical trials show for the first time and with methodological strengths that, in TNBC and HER2-positive breast cancer patients, post-surgical capecitabine and T-DM1, respectively, can improve prognosis when the disease persists after neoadjuvant chemotherapy. Therefore, the role of pCR as a treatment endpoint and a guide for further treatment decisions is now demonstrated. On account of these results, neoadjuvant chemotherapy becomes not an option, but rather the preferred treatment strategy for more and more TNBC and HER2-positive breast cancer patients in clinical practice.