Prediction of progression according to (a) 0.05 threshold CEA kinetics value previously identified (primary endpoint), (b) baseline circulating marker median value and (c) kinetics circulating marker median value. CA19-9, carbohydrate antigen 19-9; CEA, Carcinoembryonic antigen; cfDNA, cell-free DNA; CTC, circulating tumour cells; ctDNA, circulating tumour DNA; L-, likelihood negative ratio; L+, likelihood positive ratio; NPV, negative predictive value; OR, odds ratio; PPV, positive predictive value; Se, sensitivity; Sp, specificity.