The visual complexity score based on losses predicts for a short time to first therapy in univariate analysis in a cohort of previously untreated CLL patients (Kaplan-Meier plots). The numbers of subchromosomal genomic losses for each patient were determined using 50kXbaI SNP array technology as described in “Derivation of a genomic complexity score, Visual methods” and the mean number of losses as determined by 2 independent observers correlated against the clinical end point time to first therapy (TTFT). Depicted are Kaplan-Meier estimates (A-F) for increasing complexity score cutoffs (eg, < N vs ≥ N lesions per genome) and TTFT estimates (months).