8;21 translocation was found in 10 AML patients. These patients exhibited a distinct clinical and haematological picture, characterized by M2 bone marrow, with rather good maturation, a high count of mature granulocytes, splenomegaly, and the absence of DIC. Complete remission as easily obtained. It was reported that the median survival is better than for other AML patients with abnormal karyotypes, but this could not be substantiated in our small series. The loss of a sex chromosome was found to be frequent and of poor prognostic significance.