An analysis of leukemic cell chromosomal features in infants
CH Pui, SC Raimondi, SB Murphy, RC Ribeiro, DK Kalwinsky, GV Dahl, WM Crist and DL Williams
Leukemic cell chromosomal findings in 27 infants were analyzed. Among the
18 cases of acute nonlymphoblastic leukemia (ANLL), all but two were
classified as monocytic or myelomonocytic. The remaining nine cases were
acute lymphoblastic leukemia (ALL), seven lacking the common ALL antigen
and two having cytoplasmic immunoglobulin (pre-B phenotype). Twenty-five
cases (93%) had an abnormal karyotype, 21 (84%) being pseudodiploid.
Chromosomal translocations were detected in 67% of the ANLL cases and in
78% of the ALL cases. Nonrandom chromosomal abnormalities included the
t(9;11)(p21-22;q23) in three cases of monocytic leukemia, inversion of
chromosome 16 in three cases of myelomonocytic leukemia with bone marrow
eosinophilia, and t(4;11)(q21;q23) in one case of ALL. Chromosomal regions
preferentially involved in infant leukemia included 11q23-25 (13 cases),
9p21-22 and 10p11-13. All but one of the 24 cases with chromosomal breakage
or rearrangement had breakpoints that corresponded to known fragile sites,
half of which were at 11q23-25, a finding that may have pathogenetic
importance. The CALLA- or pre-B phenotype and the presence of chromosomal
translocations in most infants with ALL provide a biological explanation
for their poor prognosis.
Volume 69,
Issue 5,
pp. 1289-1293,
05/01/1987
Copyright © 1987 by The American Society of Hematology
