Intensive sequential chemoterapy with etoposide, mitoxantrone and cytarabine (EMA) as salvage in patients with AML relapsing after hematopoietic stem cell transplantation.

e18537 Background: Relapse after allogeneic hematopoietic stem cell transplantation ( HSCT) for AML is the main cause of treatment failure.The optimal treatment strategy for patients with AML relapsing after HSCT remains controversial. We evaluated the efficacy of intensive sequential chemotherapy with etoposide,mitoxantrone and cytarabine as salvage therapy in patients with AML relapsing after alloHSCT. Methods: Fifteen AML patients relapsing after HSCT who were treated with EMA regimen between January 2015 and December 2016 were analysed retrospectively. EMA regimen consisted of mitoxantrone 12 mg/m² on days 1-3, etoposide 200 mg/m² on days 8-10 and cytarabine 500 mg/m² on days 1-3 and 8-10. Results: Median age was 49 ( range 22-64) years. At transplantation , 12 patients were in CR ( 10 CR1 and 2 CR2) , 3 patients had active disease. 9 donors were matched related, 3 were matched unrelated and 3 were haploidentical. Median time from transplantation to relapse was 163 ( 62-576) days. Complete response ( CR) was achieved in 7 of 15 patients ( 46.6 %). Five patients died during treatment before assessment of response to treatment with a median day of 32 due to infection. Three patients did not respond to treatment. All patients suffered grade 4 neutropenia and thrombocytopenia. Neutropenic fever was obseved in all patients. Grade 2-3 a GVHD was observed in 10 patients (66%) during EMA chemotherapy at a median day of 15. Further treatment was given in 6 patients who achieved CR with EMA : 2 patients underwent second allogeneic HSCT, 1 patient underwent second haploidentical HSCT, 2 patients were treated with DLI, 1 patient was treated with azacytidine-DLI combination. Median OS was 100 d ( range 24-402). Median duration of OS in responding patients were 248 d ( 67-402). At last folllow-up 3 patients are still alive and disease free. Conclusions: Intensive sequential chemotherapy with EMA is an efficacious option as salvage therapy in patients with AML relapsing after HSCT. However further treatment strategies such as second transplantation, DLI after chemoterapy or maintanence with targeted drugs are required to obtain long term remission.