Breast conserving surgery and locoregional control after neoadjuvant chemotherapy.
The management of breast malignancy and the role of neoadjuvant systemic therapy has continued to evolve over the past 50 years. Survival equivalence with adjuvant systemic therapy is well accepted and demonstrated in several clinical trials. However, strong association with survival outcome and pathologic complete response emerged. Assessment of tumor response, as a surrogate for outcome, continues to be a driver for neoadjuvant therapy with increased applicability in the setting of sophisticated understanding and implications of breast tumor biology and molecular subtype. Furthermore, tumor response to neoadjuvant therapy can significantly impact local regional therapy decision-making by down-staging disease without compromising local regional control. This includes facilitation of breast conserving surgery and increased eligibility for limited axillary surgery in selected patients. Furthermore, the omission of surgery in the setting of exceptional response to neoadjuvant chemotherapy, the ultimate breast conserving strategy, is being actively studied. With further refinement of systemic and targeted therapies, neoadjuvant systemic therapy continues to provide a robust mechanism for innovation in local regional management paradigms with increased attention to individualized breast oncologic care.