A log2FC heat map (with simple genes as rows and tumor types as columns) could be used to check of the different "general" disregulation of each tumor type before sending them in to be checked with GSEA.
The idea is that if some tumors are heavily favoring up-or down regulation this might have an impact to the GSEA output.
A 'log2FC threshold' could be established to not make the plot too noisy.
A log2FC heat map (with simple genes as rows and tumor types as columns) could be used to check of the different "general" disregulation of each tumor type before sending them in to be checked with GSEA.
The idea is that if some tumors are heavily favoring up-or down regulation this might have an impact to the GSEA output.
A 'log2FC threshold' could be established to not make the plot too noisy.