Reducing locoregional treatments in low risk early invasive breast cancer.

Improved outcomes, particularly the marked reduction in locoregional recurrence, and the increasing numbers of survivors of early breast cancer, have led to the wish to reduce treatment morbidity, without compromising long-term outcomes. Trials to assess reduced breast and axillary surgery, radiotherapy and endocrine therapy have all been conducted and led to new standards of care and reduced toxicity. In some cases, however, implementation of research findings has been compromised by a relative lack of quality control in trials, substitution of a de-escalated treatment by an alternative, a lack of patient-relevant endpoints and the difficulties in the design and powering of 'non-inferiority' trials. We summarize the current landscape of care and clinical research in this area, explore the problems identified in some studies and suggest how they may be mitigated.