General report on the Second International Workshop on Chromosomes in Leukemia.

The workshop participants were able to establish that the t(8;21) and t(15;17) are each definitely associated with a particular type of ANLL, namely, AML-M2 and APL-M3 and M3 variant, respectively. Both translocations, particularly the t(15;17), have an uneven geographical distribution which cannot presently be explained. The data also show that patients with preleukemia and an abnormal karyotype have a very poor prognosis with a fatal outcome in 60%, compared with only 30% for patients with a normal karyotype.