Cytogenetically different leukemic clones at relapse of childhood acute
lymphoblastic leukemia
SC Raimondi, CH Pui, DR Head, GK Rivera and FG Behm
Department of Pathology, St Jude Children's Research Hospital, Memphis, TN
38105.
Sequential analysis of blast cell chromosomes in 98 cases of acute
lymphoblastic leukemia (ALL) disclosed entirely different karyotypes for
nine patients at the time of relapse. The presenting clinical,
immunophenotypic, and cytogenetic features of this subgroup were similar to
those of the 89 patients without major karyotypic shifts. The median length
of initial remissions in these nine patients, all of whom received
intensive multiagent therapy, was 24 months (range, 6 to 35); responses to
subsequent treatment have been uniformly poor. Prominent cytogenetic
changes included a gain of modal chromosome numbers in five cases, a loss
of chromosomes in two, and the acquisition of an 11q23 rearrangement in
three. We propose several different mechanisms to account for these
findings. In one, the presence of an entirely different ALL karyotype at
relapse may represent induction of secondary leukemia analogous to the
well- described entity of epipodophyllotoxin-related secondary acute
myeloid leukemia (AML).
Volume 82,
Issue 2,
pp. 576-580,
07/15/1993
Copyright © 1993 by The American Society of Hematology
