[Efficacy and safety of Sorafenib as monotherapy to FLT3-ITD positive acute myeloid leukemia].

Objective: To explore the efficacy and safety of Sorafenib as monotherapy to FLT3 positive acute myeloid leukemia (AML). Methods: From April 2014 to December 2015, fourteen AML patients with FLT3 positive, 7 males and 7 females with a median age of 42 (range: 14-81) years old, were enrolled in this study. Of the 14 cases, 4 were de novo cases, 9 refractory cases and 1 relapsed case, including 78.6% patients with severe complications and 57.1% patients with KPS score less than 60 [the median KPS score was 45 (20-70) ]. The administration of Sorafenib was 400 mg twice daily and Sorafenib was continued if tolerated. The treatment response was evaluated by MICM and the data were analyzed by paired samples t test before and after Sorafenib treatment. Results: The peripheral blood WBC count [4.2 (0.9-11.8) ×10(9)/L vs 39.6 (2.3-209.5) ×10(9)/L, P<0.001 ], the percentage of peripheral blast cell [0.07 (0-0.54) vs 0.53 (0-0.94), P<0.001] and the percentage of bone marrow blast cell [0.266 (0.020-0.880) vs 0.604 (0.180-0.900), P=0.003] were significantly decreased after Sorafenib monotherapy compared with before. The overall response rate was 57.1% (8/14), including 5 cases (35.7%) with complete remission (CR). Of 4 de novo cases, 2 achieved CR, 1 with PR, 1 with NR; 3 of 10 refractory and relapsed patients achieved CR and 2 cases achieved PR, 5 cases NR. The median duration of achieving molecular remission (FLT3-ITD negative) after Sorafenib was 46(33-72) days, and the median progression free survival (PFS) was 53 (28-175) days. Conclusion: Sorafenib shows activity in FLT3-ITD mutation positive AML patients. Sorafenib monotherapy could be used as a treatment option for elderly patients or patients with severe complications, and refractory and relapsed patients with not suitable for intensive chemotherapy.