Using aromatase inhibitors in the neoadjuvant setting: evolution or revolution?

Area of Science:

• Oncology
• Endocrinology
• Breast Cancer Research

Background:

• Locally advanced breast cancer (LABC) still has a poor prognosis despite treatment advances.
• Neoadjuvant chemotherapy improves breast conservation but not survival rates.
• Endocrine therapy is emerging as a neoadjuvant option, especially with routine receptor status assessment.

Purpose of the Study:

• To evaluate neoadjuvant endocrine therapy (NET) as an alternative to chemotherapy for LABC.
• To assess the efficacy of aromatase inhibitors (AIs) in the neoadjuvant setting.
• To explore the role of NET in hormone receptor-positive breast cancer.

Main Methods:

• Review of early studies on neoadjuvant tamoxifen.
• Analysis of recent trials using third-generation aromatase inhibitors (AIs).
• Focus on carefully selected hormone receptor-positive patients with LABC.

Main Results:

• Early NET with tamoxifen showed inferior response rates compared to chemotherapy.
• Neoadjuvant AIs demonstrate superiority over tamoxifen in the neoadjuvant setting.
• Response rates for neoadjuvant AIs in selected hormone receptor-positive patients are comparable to neoadjuvant chemotherapy.

Conclusions:

• Neoadjuvant endocrine treatment with aromatase inhibitors is a viable alternative for postmenopausal women with hormone receptor-positive LABC.
• NET with AIs is particularly effective for large tumours or LABC.
• Neoadjuvant trials facilitate biomarker discovery and identify therapies for further adjuvant testing.