Idiotype as a tumor-specific marker in childhood B cell acute lymphoblastic
leukemia
WL Carroll, MP Link, ML Cleary, S Bologna, C Carswell, MD Amylon, SD Smith and R Levy
Department of Medicine, Stanford University School of Medicine, CA.
Immunoglobulin (Ig) or idiotype (Id) is a tumor-specific target in those B
cell malignancies that express this molecule on their surface. We explored
the biology of B cell acute lymphoblastic leukemia (B cell ALL) using Id as
a tumor marker. In this report we describe the development of anti-Id
monoclonal antibodies (MAB) for two children with B cell ALL. These
reagents were used retrospectively to study tumor kinetics and to detect
residual disease after chemotherapy. In both cases serum Id values were
strikingly high at diagnosis (1.2 mg/mL and 10.8 mg/mL), suggesting that
the tumor cells were relatively mature B cells capable of significant
antibody production. In both patients the serum Id levels fell with the
institution of therapy and confirmed that the patients were in remission.
Increasing serum Id predicted relapse four months before conventional
methods in patient 1, and Id proved to be a more sensitive measure of tumor
burden than Southern blot analysis of rearranged Ig genes in bone marrow
samples. Surprisingly, low levels of Id were redetected in the second
patient just before completing therapy and have persisted for over a year
despite the absence of clinical evidence of recurrent disease. Thus, serum
Id levels reflect tumor burden during initial therapy but may not
necessarily predict tumor progression after a complete clinical remission.
Volume 71,
Issue 4,
pp. 1068-1073,
04/01/1988
Copyright © 1988 by The American Society of Hematology
