Clinical analysis of 82 cases of acute promyelocytic leukemia with PML-RARα short isoform in children and adults

Background Acute promyelocytic leukemia (APL) with PML/RARα fusion gene is a distinct variant of acute myeloid leukemia. According to the different break sites of the PML gene, there are three transcripts: Long (bcr1), Variant (bcr2) and Short (bcr3). Methods We retrospectively analyzed 82 APL cases with PML-RARα short isoform. Results A total of 384 patients with APL were seen, of which 85(22.14%) had PML/RARα short isoform (bcr3) and 82 met the inclusion criteria. The median age was 33.5 years (range, 2-72 years). The incidences of hemorrhage in the intermediate- and high-risk group were higher, but only the incidence between medium and low risk differed statistically ( P=0.006) , and the incidences of fever, fatigue, splenomegaly, and lymph node enlargement and differentiation syndrome (DS ) in those groups were not statistically significant ( P 0.05). FLT3 gene mutation rate and the mortality rate of the high-risk group were significantly higher than that of other groups ( P =0.040 and P =0.004, P= 0.041 and P =0.037, respectively). The mortality rate was lowest (4.26%) in the group treated with ATRA combined with arsenic and anthracycline. The 3-year OS and the 3-year DFS of the low and intermediate-risk group were better ( P =0.019 and P =0.017, respectively). Conclusions ATRA combined with arsenic and anthracycline had significant impact on outcomes in APL with PML-RARα short isoform.