Figure 4

Distant disease-free survival according to our proposed new definitions of intrinsic molecular subtypes and tumor grades. Hazard ratios and 95% confidence intervals (CIs) were calculated using a multivariable Cox proportional hazards regression model adjusted for pathologic tumor stage, pathologic node stage, tumor grade, peritumoral vascular invasion and menopausal status. P = 0.33 for the interaction between tumor grade and new intrinsic molecular subtype. The percentages of patients with luminal A–like breast cancer who received adjuvant chemotherapy were 9.5% (G1), 24.73% (G2) and 42.0% (G3). Similarly, 21.3%, 38.7% and 60.5% of patients with G1, G2 and G3, luminal B–like breast cancer, respectively, received adjuvant chemotherapy.