What does it mean gene sets are upregulated in phenotype for example cancer ?

After performing GSEA for phenotypes normal vs cancer, the report has been obtained and in it: 

35 / 50 gene sets are upregulated in phenotype cancer. I know the meaning of a gene is up regulated or down regulated but what does it mean gene sets are up regulated? does it mean that all genes inside the gene sets were up regulated ? or what ?

Thanks 
Hello

GSEA is a tool that determines whether a set of genes defined *a priori* shows concordant and statistically significant differences between two biological states. For that reason, upregulated gene sets mean that the genes contained in these gene sets are (the vast majority) upregulated, so the program determines that this gene set is upregulated.

Best