[Clinical Effect and Safety of CCLG-ALL 2008 (high risk group) Protocol in the Treatment of Childhood Mixed Phenotype Acute Leukemia]

Objective: To investigate the clinical effect and safety of Chinese Children's Leukemia Group (CCLG)-ALL 2008 (high risk group) protocol in the treatment with childhood Mixed phenotype acute leukemia (MPAL).

Methods: The clinical data of 15 new diagnosed patients with MPAL treated in our hospital from January 2013 to December 2017 were retrospectively analyzed, and received CCLG-ALL 2008 (high risk group) protocol chemotherapy.

Results: One patient gave up treatment after diagnosed, and 14 children with MPAL after induction remission chemotherapy, 3 patients gave up, and 5 patients received consolidation chemotherapy, and 6 patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT). The complete remission (CR) rate was 85.7% at d33 of induction remission chemotherapy. The serious adverse event and treatment-related mortality (TRM) rate was 71.4% and 14.3%, respectively. The recurrence rate was 21.4% and the median time of relapse was 12(9.7-18.4) months. Except for 4 patients who gave up treatment, the 5-year event-free survival (EFS) rate in the other 11 patients was (54.5±15.0)%. The 5 years EFS of 4 patients who received consolidation chemotherapy was significantly lower than the 6 patients who received allo-HSCT after CR (25.0%±21.7% vs 83.3%±15.2%, P=0.033).

Conclusion: The CCLG-ALL2008 (for high-risk group) protocol in treatment of children with MPAL can get a high CR rate, but also with a high incidence of SAE. The patients received allo-HSCT after CR may have a good prognosis.