Favorable cytogenetic abnormalities in secondary leukemia.

The authors report on five patients with secondary leukemia (SL) and one of the "specific" chromosomal rearrangements usually encountered in de novo acute nonlymphoblastic leukemia: inv(16), t(15;17), t(8;21), and t(9;11). They were characterized by solid tumor as the primary malignancy in four of five cases, absence of preleukemic phase in all cases, and myelodysplastic features in one of five cases only. All patients achieved complete remission (CR) with aggressive chemotherapy. Only two relapsed, but follow-up is still limited in the three remaining cases. Cytogenetic analysis is important in all younger patients with SL, especially if unusual features (such as absence of preleukemic phase or myelodysplastic features) are found. Aggressive chemotherapy appears to be indicated in those patients if a "specific" rearrangement is found.