Kaplan-Meier metastasis-free survival curves for ER+/HER2- breast cancer. Comparison of treatment arms (FEC vs. FEC-P) in (A) the EP low-risk group (n = 141) and (B) the EP high-risk group (n = 414). The cutoff point for EP was prespecified at 5. Numbers in parentheses indicate the 95% confidence intervals of the hazard ratios. FEC: fluorouracil, epirubicin and cyclophosphamide; FEC+P: fluorouracil, epirubicin and cyclophosphamide followed by eight weekly courses of paclitaxel.