seline files for cancer samples only

[20221122]

Hello, I have a total of more than 100 files on cancer, but there is absolutely no corresponding normal samples to use as a control, I see that I can use the baseline files provided by github, but I am facing a problem that the reference I am using is human_g1k_v37_decoy.fa. what is the solution for this situation please? Can I use all the files to create the baseline first and then analyse all the files later?