Rethinking the Local Therapy of Breast Cancer: Integration of Biology and Anatomy.

Overview

Local control has traditionally been considered a function of disease burden. Local control is now known to differ among biologic subtypes of breast cancer and is greatly improved with the use of systemic therapy. This offers opportunities for decreasing the morbidity of treatment and individualizing local therapy. The use of smaller margins in breast-conserving surgery and elimination of axillary dissection for some node-positive breast cancer patients are current examples of leveraging the benefits of systemic therapy to reduce surgery. Emerging evidence indicates that molecular profiling can identify patients at high and low risk for locoregional recurrence after surgery in a more accurate way than tumor burden, potentially allowing individualization of the use of postmastectomy and comprehensive node field irradiation. Future clinical trials should incorporate both disease burden and molecular profiling when examining treatment strategies.