Panel a) shows the relationship between melphalan AUC (N=118), and panel b) shows the relationship between log IC50 (N=115) relative to mucositis grade. The association between AUC or log IC50 values and worst mucositis grade (0 & 1 vs 2 & 3) was analyzed using Wilcoxon rank sum test with continuity correction (two-sided). The numbers of patients with worst mucositis grade 0, 1, 2, 3 were 44, 54, 16, and 4, respectively for the AUC evaluation (N=118 total). The numbers of patients with worst mucositis grade 0, 1, 2, 3 were 43, 52, 16, and 4, respectively for the log IC50 evaluation (N=115 total).