Significance of chromosomal studies in leukemia: Karyotype analysis of 28 cases of leukemia and 2 cases of myelofibrosis

Chromosomal studies were carried out in 30 patients including 28 cases of leukemia and 2 cases of myelofibrosis. 25 of them were studied by trypsin-Giemsa banding technique and the other 5 by ordinary Giemsa stain. 19 of the 30 cases showed chromosomal abnormalities. All of the 9 cases of chronic myelocytic leukemia (CML) had Ph1 chromosome and 8 of them were proved to have typical 9:22 translocation. 4 cases in the blastic stage of CML also had Ph1 chromosome and in 3 of them additional chromosomal changes were found. Of these three, 2 had double Ph1 and one had a new structural rearrangement which appeared to be t(3:6), (q27, q13-15). Of the 11 cases of acute leukemia 3 had chromosomal abnormalities. One of them was a Ph1 positive acute lymphocytic leukemia (ALL) and the other 2 had gaining or missing in groups C, D or E. Two of the 3 preleukemias had an additional chromosome in group G. One of the two cases of primary myelofibrosis had Ph1 chromosome and a new chromosomal change t (1:11) (p34; q13) was found on entering blastic transformation. One case of lymphosarcoma cell leukemia showed no chromosomal abnormality. Karyotype analysis is described in detail of the two cases with new chromosomal abnormalities. Diagnostic and prognostic significance of chromosomal changes in various types of leukemia is discussed.