In contrast to these results, a previous study associated elevated KLF4 transcript levels with prolonged DFS.56 As overall survival, DFS and DMFS correlate strongly in breast cancer, the utilization of these different endpoints seems unlikely to account for the distinct results.57, 58, 59 Instead, the discrepancy may be attributed to the analysis of different patient populations, to differences in sample size or to methodological differences in sample processing. This evidence concerns the gene KLF4 and breast cancer.