Current Status of Neoadjuvant Endocrine Therapy in Early Stage Breast Cancer
Neoadjuvant endocrine therapy (NET) with Ki67-based response monitoring is a practical, cost-effective approach to the management of clinical stage II and III estrogen receptor-positive (ER+) breast cancer. In addition to marked improvements in rates of breast conservation, the identification of extreme responders on the basis of the preoperative endocrine prognostic index (PEPI) provides a rationale to avoid chemotherapy on the basis of highly favorable prognosis in some patients. Finally, samples accrued from patients treated with neoadjuvant therapy are providing valuable insights into the molecular basis for intrinsic resistance to endocrine therapy and promise a more rational basis and precise approach to the systemic treatment of ER+ breast cancer.
KeywordsBreast cancer Endocrine therapy Neoadjuvant Aromatase inhibitors Breast-conserving surgery
Compliance with Ethical Standards
Conflict of Interest
Tomás Reinert has received research funding from AstraZeneca and has received speaker’s honoraria from AstraZeneca, Novartis, and Pfizer.
Rodrigo Gonçalves declares that he has no conflict of interest.
Matthew J. Ellis has received clinical trial support from Novartis (P024 and Z1031 trials) and Pfizer (Z1031 trial); has received compensation from AstraZeneca, Pfizer, and Novartis for service as a consultant; and has licensed PAM50 patents to NanoString for Prosigna®. The commercial version of PAM50 is not mentioned within this article.
Human and Animal Rights and Informed Consent
Dr Ellis performed the Preoperative Letrozole Study and the Z1031 Study. He was a coinvestigator of the P024 Study. All these studies on human subjects were approved by the relevant ethics committees as outlined in the publications cited.
References and Recommended Reading
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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