After DNA extraction of 51 available FL FFPE (n=33 from training cohort and n=18 from validation cohort), samples were sequenced on an Illumina MiSeqDx using our lymphopanel of 43 genes involved in B-cell lymphomagenesis.17 (link) Sequencing and data analysis was performed as previously described17 (link),18 (link) (see details in the Online Supplemental Methods).