Objective To evaluate the impact of kinetics of molecular remission via ret
ro-transcriptase polymerase chain reaction (RT-PCR) assay on the long-term
survival in patients with acute promyelocytic leukemia (APL).
Methods Seventy patients with newly-diagnosed APL in remission were involve
d in this study. Monitoring of minimal residual disease (MRD) was performed
regularly by RT-PCR assay for PML-RAR alpha during consolidation.
Results A 5-year relapse-free survival (RFS) and overall-survival (OS) were
estimated as 46.8% +/- 8.4% and 69.9% +/- 9.4% for the whole group. Fifty-
two (74.3%) patients got negative RT-PCR result at least once. Serial monit
oring of RT-PCR was available in 38 cases and 24 (63.2%) patients presented
with persistent negative PCR results. The achievement and continuous negat
ive RT-PCR result was significantly related to the RFS.
Conclusions Achievement of negative RT-PCR in remission is associated with
favorable RFS and OS. Continuous negative RT-PCR results are associated wit
h long-term relapse-free survival and may be considered as potentially cura
tive. RT-PCR assay for detection of MRD should be performed regularly durin
g post-remission period as an important prognostic factor.