Real-world data on the dose-related effect of arsenic trioxide in the relapse of acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) has become a highly curable disease with all-trans retinoic acid-based regimens. However, following the administration of arsenic trioxide (ATO), the relapse rate remains at 1-10%. It is not known whether the dosage of ATO is associated with the relapse rate in real-world settings. According to 2019 National Comprehensive Cancer Network guidelines, the recommended cumulative ATO dosage in post-remission therapy is 7.95-12 mg/kg in APL. In the current study, 112 patients with newly diagnosed APL receiving a combination of all-trans retinoic acid, anthracycline-based chemotherapy and different dosages of ATO for variable courses, were divided into the high-dose (ATO dosage, ≥12 mg/kg) and low-dose groups (ATO dosage, 6 mg/kg. In conclusion, the relapse rate of APL was significantly associated with ATO dosage in post-remission therapy. An increased ATO dosage may serve as a protective factor of relapse. ATO dosage should therefore reach up to 12 mg/kg, with consideration to reduce the dosage in the future.