Chromosome studies on 30 Chinese patients with acute nonlymphocytic leukemia in Taiwan

Cytogenetic studies were performed on 32 consecutive Chinese patients with de novo acute nonlymphocytic leukemia (ANLL) in Taiwan. Of the 30 patients with adequate specimens, 20(66%) had clonal chromosome abnormalities. Structural rearrangements were detected in 18 of them. Seven (four were children) of the 16 patients with M2 ANLL had t(8;21). All six patients with acute promyelocytic leukemia (APL; M3 subtype) had t(15;17). Two patients with M4 type leukemia and abnormal bone marrow eosinophils had inv(16)(p13q22). Another M4 patient with a mild increase of morphologically normal eosinophils in the bone marrow had an abnormal chromosome #16, t(1;16)(q21;p13) in which 16q22 was not involved. One patient with M5 ANLL had t(9;11). Only two patients had a numerical change as the sole abnormality. None of the patients had loss or deletion of chromosome #5 or loss of chromosome #7, and only one had a deletion of 7q. This study revealed a high incidence of t(8;21), t(15;17), and a low incidence of -5/5q- or -7/7q- in Chinese patients with ANLL.