The importance of locoregional control in the treatment of breast cancer and its impact on survival

Background. Different schools of thought regarding the natural history of breast cancer and how it relates to the importance of local control in affecting survival have generated controversy over the optimal treatment of early breast cancer. Parting with traditional thinking that some disease is localized, in which cases local control is important for survival, another view of the natural history of the disease argues that local control is not of value to survival. This commentary will review the evidence and attempt to evaluate the effect of modern adequate local treatment on survival. Methods. A review of the pertinent literature on the treatment of breast cancer and an analysis of recent clinical trials and metaanalysis are presented. Results. Evaluation of the recent literature and metaanalysis demonstrates that adequate local regional treatment, especially radiation therapy in the treatment of breast cancer, does effect survival significantly. Conclusions. Results of modern effective local treatment of breast cancer substantiate the claim that some breast cancer is localized. Data show that tumor size, lymph node involvement, tumor grade, and other prognostic factors are important predictors of whether a tumor is localized and therefore amenable to local treatment. Smaller tumors generally are most likely to be localized. Recent studies on modern irradiation techniques show that adequate effective irradiation of localized disease, including appropriate treatment of all nodal areas when needed and limited radiation to sensitive organs, can significantly improve survival and, in high‐risk patients, enhance the effect of systemic treatment in improving survival.