We found that RNASE2, ARRDC2, PRX, KCNQ4, and DLK1 were significantly predictive in relapse-free survival of all breast cancer patients and in all subtypes whereas EGLN3, DYNLT3, TUBGCP6, HOXA6, and DCHS2 were predictive in all patients, and all subtypes except for those of HER2 subtype, and ENPP6, WDR86, ALX4, CLEC3A, P4HA3, PRR13, CTHRC1, and OTUD7A were predictive in all patients and in at least one subtype of breast cancer patients (data not shown). This evidence concerns the gene KCNQ4 and breast cancer.