1,248 consecutive cases of hematologic neoplasm, diagnosed according to the FAB classification at the Department of Medicine during the period between January 1986 and December 1995, were analyzed cytogenetically by GTG and QFQ banding techniques according to the ISCN 1984 at Human Genetics Unit, Department of Pathology. Of the total 1,248 cases, only 1,171 cases were successfully karyotyped. These cases comprised of 530 ANLL, 80 ALL, 322 CML, 3 CLL, 5 CMMoL, 84 lymphoma and 147 MDS. The age of patients range between less than 1 year old and 72 years old. The main age group observed in all type of neoplasm with chromosome aberration was 20-39 years which included 15.2% of all patients. Male and female patients were equal (ratio 1:1) in occurrence both for the total number and the number with chromosome aberrations.

Chromosome aberrations were found differently in each type of neoplasm. 43.2% of abnormal karyotypes were detected in ANLL, 35.0% in ALL, 80.1% in CML, 32.1% in lymphoma and 29.9% in MDS. For CLL and CMMoL, only small number of patients (total of 8 cases) were diagnosed and all (100%) were successfully karyotyped with 2 chromosome aberration cases. In ANLL, the aberrations specifically associated with the hematologic subtypes were t(8;21)(q22;q22) and M2 with specificity of 0.77 and rather high frequent loss of either X or Y; t(15;17)(q22;q11-21) and M3 with specificity of 0.45 as well as inv(16)(p13q22) and M4 with eosinophilia (specificity = 1). The aberration in the latter case was found to be 9.7% of all M4 subtype. The specific chromosomal change predominantly t(9;22)(q34;q11) was observed in ALL. The others were t(4;11)(q21;q23), +21 and hyperdiploidy with modal number of >50 chromosomes. In CML the majority of aberrations was the standard t(9;22)(q34;q11), therein only 5.6% had the variant/complex translocation involved 3 or 4 chromosomes. Related abnormal clones were detected in 9.8% of cases which mostly were in blastic crisis. The additional abnormal chromosomes were +22q-, i(17q), +8 and +19. The most specific rearrangement detected in lymphoma was t(8;14)(q24;q32) in Burkitt’s lymphoma. Common chromosome changes in MDS were –7, +8 and del(5q) in order of decreasing frequency of 25%, 15.9% and 11.4%. In most of the cases the aberration occurred solely.

Of the cases presented in this report, there was an agreeable result with those of previous publications. The cytogenetic investigations of neoplastic cells are, in principle, important for determining the characteristics karyotypic profile of a given tumor type and this information can be implemented both to clinical application and basic research.