Detection of residual leukemic cells in patients with acute promyelocytic
leukemia by the fluorescence in situ hybridization method: potential for
predicting relapse
L Zhao, KS Chang, EH Estey, K Hayes, AB Deisseroth and JC Liang
Department of Laboratory Medicine, University of Texas M.D. Anderson Cancer
Center, Houston 77030.
The translocation between chromosomes 15 and 17, t(15;17)(q22-24;q11- 21),
is present in the bone marrow cells of most patients with acute
promyelocytic leukemia (APL). Although conventional cytogenetic methods are
useful for diagnosing this disease, difficulties are experienced in
detecting residual disease among those patients who have achieved
remission. In this study, we used the fluorescence in situ hybridization
(FISH) method to attempt to detect residual leukemic cells in 10 APL
patients in clinical remission. The duration of remission ranged from 2 to
93 months at the time of study. Multiple bone marrow samples were analyzed
by FISH in most patients. In 6 patients, no cell with t(15;17) was found.
These patients remain in complete remission at present (approximately 25 to
33 months since first studied by FISH). In 4 patients, low frequencies of
cells with t(15;17) were observed in at least one bone marrow sample
examined. All of these patients relapsed within 1 to 14 months. No cell
with t(15;17) was identified by the conventional G-banding method in any
sample. The FISH results correlated well with that of a two-round nested
reverse transcription polymerase chain reaction assay that was performed on
the same samples. Thus, our study suggests that FISH is potentially a
useful tool for detecting residual APL cells and for identifying patients
at high risk of relapse.
Volume 85,
Issue 2,
pp. 495-499,
01/15/1995
Copyright © 1995 by The American Society of Hematology
