Patients with acute myeloid leukemia (AML, equivalent to acute non-lymphoblastic leukemia [ANLL]) who were studied at the Fourth and Sixth International Workshops on Chromosomes in Leukemia and who have long survival have been re-assessed to identify factors which may be associated with good prognosis in AML. In a long-term survivor (LTS) group, there were more cases than expected in each age decade below 50, more cases than expected with FAB type M3, and fewer cases than expected of secondary leukemia. Of the distribution of chromosome abnormalities, t(15;17), t(8;21), and inv/del(16) were over-represented, and -5, -7, and rearrangements of 11q were under-represented. Multivariate analysis of all patients showed that age group, cytogenetic classification, FAB type, and sex all had independent, significant effects on survival. A new observation from a very small subgroup of patients was that deletion of 7q without concurrent abnormality of chromosome 5 appeared to be associated with a good prognosis.