PREMATURE CENTROMERE DIVISION OF THE CHROMOSOMES AT THE DIFFERENT STAGES OF ACUTE LYMPHOBLASTIC LEUKEMIA IN INFANTS. 142

Abstract

The evidence of premature centromere division of the metaphase chromosomes as a new prognostic cytogenetic marker of infant's acute lymphoblastic leukemia (ALL) is suggested. The frequency of PCD cells (premature centromere division of 1-10 chromosomes per cell) and PA (premature centromere division of 50-100% chromosomes) was evaluated in the lymphocytes and bone marrow cells of children with ALL in the acute phase of disease and in remission. PA practically were not found in the lymphocytes of healthy children, but PCD have been registered at a rate no more than 3% of the examined cells. However, in acute phase of ALL the PCD level averaged from 26,9±2,0 per 100 lymphocytes and 40,3±8,6 per 100 bone marrow cells. A significant positive correlation between PCD and blast levels was noted (p=0,85, P<0,01). This allows to assume that PCD cells most probably correspond to blast cells. The PA level averaged from 3,9±1,1 per 100 cells reaching 15,5±8,3 in bone marrow cells. In remission PA practically were not found and the PCD level decreased significantly. The prognosis of disease correlated with PA level in acute phase: If the PA level in acute phase of ALL was 0-8 per 100 cells (average 3,2%), remission was not practically achieved or relapse presented soon. Moreover, if the PA range was 2-70 per 100 cells(average 14,8) a sustained remission was registered. We suggest that PA and PCD levels could be used as prognostic markers of ALL in infants.