RB1 and breast carcinoma: Multivariate Cox proportional hazard model‐derived hazard ratio and 95% confidence interval (CI) comparing the relapse‐free survival and overall survival in women whose primary breast cancer harbored mutations in any of the six genes (FGFR3, RB1, APC, KIT, PTEN, and MAP2K4) compared with patients who did not harbor mutations in any of those genes.