Survival from diagnosis of t-MDS/t-AML by recurring cytogenetic abnormalities. The number of patients remaining at risk at 1, 2 and 4 years, respectively, were as follows: 15, 7, and 4 for abnormal 5; 34, 11, and 3 for abnormal 7; 15, 3, and 1 for abnormal 5 and 7; 14, 7, and 4 for recurring balanced rearrangements; 14, 7, and 3 for other clonal abnormalities; and 10, 6, and 2 for normal karyotype.