Objective: To evaluate the efficacy of BCH-03 and CCLG-08 protocols in treating E2A-PBX1 pediatric acute lymphoblastic leukemia (ALL).
Method: From January 2003 to January 2011, 59 ALL patients identified as E2A-PBX1 were analyzed in a retrospective study. There were 37 and 22 patients treated with Protocol BCH-03 and CCLG-08, respectively. The clinical characteristics at diagnosis, response to early treatment, the time of relapse, relapse-free survival (RFS) and event-free survival (EFS) in the two groups were analyzed.
Result: There were no significant differences in gender, age, initial white blood cell count, the central nervous system involvement, immunophenotype, prednisone response, the rate of complete remission, and the time of relapse between the two groups (P > 0.05). The only difference in induction therapy of the two protocols existed in the glucocorticoids used, that is, BCH-03 used 60 mg/m(2) prednisolone and CCLG-08 used 6 mg/m(2) dexamethasone. The doses of vincristine, daunorubicin and L-asparaginase were the same in the two groups. At the end of induction therapy, the MRD negativity rate in BCH-03 group was significantly higher than that in CCLG-08 group (84.2% vs. 47.1%, P = 0.018). The incidences of severe infection of the two groups during induction of remission were similar (P = 0.135). The EFS of BCH-03 group was significantly superior to that of CCLG-08 group (94.5% vs. 71.5%, P = 0.010), and the RFS of BCH-03 group tended to be better than that of CCLG-08 group (94.5% vs. 78.6%, P = 0.059).
Conclusion: Compared to Protocol CCLG-08, Protocol BCH-03 was more effective for pediatric E2A-PBX1 ALL, and 60 mg/m(2) prednisolone was more suitable for the induction therapy of this subtype of pediatric ALL.