Info
acute promyelocytic leukemia (APL)
(Blood 2009;113:1875)
Rare, ~8% of AML in U.S.
90% cure rates
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Atypical promyelocytes (large, granular cells; bilobed nuclei) in blood and bone marrow
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Defined by translocation of retinoic acid receptor: t(15;17); PML-RARA (>95% of cases)
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Medical emergency with DIC and bleeding common
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Remarkable responses to all-trans-retinoic acid (ATRA) & arsenic trioxide (ATO) which induce differentiation of leukemic blasts.
- ∴ early initiation of ATRA if APL suspected
Non-high-risk APL 🍏
- ATRA + ATO (induction + 4 cycles consolidation)
- → CR ~100%;
- event-free survival 97% and overall survival 99% at 2 y (NEJM 2013;362:111)
High-risk APL 🍎
- WBC >10k at diagnosis.
- No clear consensus.
- In general, chemo (anthracycline or gemtuzumab ozogamicin) added to ATRA + ATO induction and consolidation.