16 6.1 Immune Response .................................................................................................................... 16 6.1.1 Derivation rules ...................................................................................................................... 16 6.1.2 Endpoint summaries .............................................................................................................. 16 6.2 Survival Assessments ............................................................................................................... 17 6.2.1 Disease- free survival (DFS) ................................................................................................... 17 6.2.2 Overall survival (OS) .............................................................................................................. 18 6.2.3 Swimmer Plots ....................................................................................................................... 19 6.3 Exploratory Analysis ................................................................................................................. 19 6.3.1 Relationship between KRAS status and recurrence survival outcomes ............................... 19 6.3.2 CA19 -9 levels and other biomarkers .....................................................................................