OS according to cytogenetic risk groups. (A) Final tree by TSSA after pruning. Internal leaves are shown by ovals and terminal leaves by rectangles. The numbers inside each internal and terminal leaf represent the number of patients dead out of the total number of patients at risk. ^*Proportion dead. (B) OS curves comparing cytogenetic risk groups identified by TSSA. (C) OS curves comparing patients with normal karyotype with patients who have an abnormal karyotype with fewer than 5 abnormalities, excluding CBF AML and rare aberrations.