ERBB2 and breast cancer: In none of the other breast cancer subtypes was a consistent difference for outcomes between tumors with predominant E and M signatures observed (Figure 5C); in the luminal A and B subtypes both E and M signatures were associated with poor OS, while in the HER2+ subtype four of the five tested E signatures (between HR = 1.67 and HR = 2.1) were also associated with worse outcomes than M signatures (between HR = 0.33 and HR = 0.75), which was significant within a 95% confidence interval for two of the five tested E and M signature pairs.