I used both of the columns for categorisation. Cases with ' new_tumor_event_indicator' as 'YES' & tumor_status' as 'WITH TUMOR' were grouped as 'resistant'. The sensitive cases would correspond to the absence of new tumor event & tumor free status. R commands are available to select rows with specific criteria in a particular column. After getting the barcodes for each group, you can use TCGAbiolinks for downloading and analysing the data. Or else you can use edgeR for differentially expression analysis. Hope this helps!