OBJECTIVETo investigate the clinical efficacy of all-trans retinoic acid (ATRA) plus arsenic trioxide (ATO) in induction and maintenance therapy in newly diagnosed acute promyelocytic leukemia (APL).

METHODSA retrospective analysis of 298 newly diagnosed APL patients from the department of hematology, First Affiliated Hospital of Zhejiang University since September 2004 to December 2013, including 177 cases with ATRA plus ATO and 116 ATRA plus chemotherapy (CT), was performed to investigate the clinical efficacy between the low-intermediate (WBC≤10×10⁹/L) and high (WBC>10×10⁹/L) risk APL patients, respectively.

RESULTSFor the low-intermediate risk patients, the relapse rate in ATRA plus CT and ATRA plus ATO are 22.0% and 6.1% (P=0.004), respectively; the 3 years estimated relapse-free survival (RFS) are 78.0% and 92.9% (P=0.021), respectively. For the high risk patients, the relapse rate in ATRA plus CT and ATRA plus ATO are 25.0% and 5.2% (P=0.035), respectively; the 3 years estimated RFS rate were 80.8% and 93.0% (P=0.021), respectively. But the rate of early death (ED), complete remission (CR) and overall survival (OS) between the two therapy protocols had no statistical difference (P>0.05).

CONCLUSIONATRA plus ATO in induction and maintenance therapy might prolong the RFS time of the low-intermediate risk APL patients and decrease the relapse rate of the low, intermediate and high risk APL patients.