Optimal Management for Residual Disease Following Neoadjuvant Systemic Therapy

Area of Science:

• Oncology
• Breast Cancer Research
• Clinical Trial Design

Background:

• Treatment sequencing for early-stage breast cancer has shifted, favoring neoadjuvant systemic therapy (chemotherapy and targeted agents) over upfront surgery.
• This approach is particularly impactful in triple-negative breast cancer (TNBC) and HER2-positive breast cancer subsets.
• Neoadjuvant therapy enables accurate prognostic assessment via residual cancer burden and can lead to tumor downstaging, potentially reducing surgical extent.

Purpose of the Study:

• To review the evolving landscape of treatment sequencing in early-stage breast cancer, focusing on neoadjuvant strategies.
• To highlight the impact of achieving pathologic complete response (pCR) on adjuvant treatment decisions and locoregional therapy de-escalation.
• To discuss the role of emerging technologies like minimal residual disease (MRD) monitoring in guiding future adjuvant interventions.

Main Methods:

• Review of pivotal clinical trials (e.g., CREATE-X, KATHERINE) evaluating adjuvant therapies post-neoadjuvant treatment.
• Discussion of ongoing clinical trials assessing treatment de-escalation strategies based on pCR status (e.g., CompassHER2-pCR, NCT01872975, NCT01901094).
• Exploration of novel monitoring techniques such as MRD detection for personalized adjuvant therapy.

Main Results:

• Adjuvant capecitabine and ado-trastuzumab-emtansine (T-DM1) improved recurrence-free survival in residual TNBC and HER2-positive breast cancer, respectively.
• Pathologic complete response (pCR) is associated with excellent long-term outcomes, permitting de-escalation of adjuvant chemotherapy.
• pCR also supports de-escalation of locoregional therapies, with trials investigating omission of radiation and axillary lymph node dissection.

Conclusions:

• Neoadjuvant therapy followed by risk-adapted adjuvant treatment represents a paradigm shift in early-stage breast cancer management.
• Achieving pCR is a critical endpoint that allows for personalized treatment strategies, including de-escalation of both systemic and locoregional therapies.
• Minimal residual disease monitoring holds promise for early detection of relapse and timely intervention, further refining adjuvant treatment paradigms.