Progression scenarios comparing ISA 2005 progression criteria to “Pavia high-risk dFLC progression.” Y-axis, Different examples of baseline and nadir values; x-axis, candidate dFLC value at time of progression for each system. For this figure, the assumption is made that patients do not have measurable M-spikes in the urine or serum at the time of progression. ISA hematologic progression (1) from CR, any detectable monoclonal protein, or an abnormal FLC ratio (light chain must double) and (2) from PR or stable response, a 50% increase in serum M-protein to >5 g/L or 50% increase in urine M-protein to >200 mg per day or FLC increase of 50% to at least 10 mg/L. Pavia “high-risk dFLC progression” requires all of the following: (1) an absolute value of dFLC of >20 mg/L; (2) a dFLC level that is at least 20% of the baseline value; and (3) a dFLC that is at least 50% higher than the nadir dFLC achieved posttherapy.