Quantification of residual risk of relapse in breast cancer patients optimally treated

Despite remarkable improvements in breast cancer survival in the last decades, a proportion of patients still relapse after treatment for early disease. Different prognostic parameters may permit to roughly quantify the residual risk of relapse after (neo)adjuvant therapy. They include: tumor stage and classical molecular features at baseline, newly proposed prognosticators (such as tumor-infiltrating lymphocytes and integrated genomic tools) and the evaluation of tumor response after primary systemic therapy. However, the performance of these factors is still suboptimal and should be improved. Further research aimed to discover new possible prognostic factors in patients who received optimal systemic therapy is needed. Moreover, to exploit at the best the potential of each of these parameters, they should be integrated into algorithms to guide treatment decisions and to select those patients who may deserve the inclusion in clinical trials.