Comparison of the performance of four staging systems in determining the prognosis of breast cancer among women undergoing neoadjuvant chemotherapy.

Purpose: Different tumor-related factors have been proposed to assess the risk of disease progression and death in women undergoing neoadjuvant breast cancer chemotherapy. Recently, besides the classical pre-treatment clinical stage (CS) and post-treatment pathologic stage (PS), estrogen receptor status and histologic grade (CPS + EG score) and HER2 results (Neo-Bioscore) have also been added to this suite of staging systems, generating new scores. The present study aims to compare the performance of these four staging systems, namely CS, PS, CPS + EG and Neo-Bioscore, in the prognosis of breast cancer in women undergoing neoadjuvant chemotherapy.