The role of posttreatment clone size on improvement of OS model. (A) A forest plot showing the result of Cox proportional hazards regression model for OS performed on the paired cohort with complete data for OS analysis (n = 223). Explicative variables are age, IPSS-M score, the largest VAF values adjusted for copy number alterations in posttreatment samples (MaxVAFpost), and clinical response per the IWG 2006 criteria (CR or not). The x-axis is log scaled. The new risk score of the novel OS model (prognostic scoring system after azacitidine treatment; PSS-AZA) is calculated according to the formula shown below the forest plot. The threshold for risk classification is also presented below the forest plot. (B) Kaplan-Meier estimates of OS per risk classes based on PSS-AZA are presented. The number of the cases at risk at each time is indicated in the tables below. P values are derived from two-sided log-rank tests. (C,D) Kaplan-Meier estimates of OS per risk classes based on PSS-AZA are presented for IPSS-M–very high-risk (C) and IPSS-M high-risk (D) group cases. Kaplan-Meier estimates of IPSS-M–based risk groups are overlaid with light-colored curves. (E) A schematic presentation of the analysis that examines the improvement of predictability. The paired cohort was randomly split into 75% training and 25% validation subsets 10 000 times and constructed a model for each training set to fit the model and calculated the concordance index (c-index) for the corresponding validation set. (F) Box plots indicating the distribution of c-index in the validation cohorts of 10 000 simulations.
