We conducted this study using the c-MYC gene, one of the genes most frequently amplified across all cancer types [34], and we validated our results using a different set of tumor samples from another institution and another frequently-amplified gene, FGFR1. We found that a high Shannon index of c-MYC copy number variation was associated with poor disease-free survival in both the test and validation sets, and we obtained similar results after excluding cases in which c-MYC was amplified, so ruling out the effect of c-MYC amplification on the diversity index. This evidence concerns the gene MYC and cancer.