With the gradual improvement and maturation of chemotherapy regimens, the complete remission (CR) rate of induction therapy for adult AML has reached 60%-80%. However, about 20-40% of patients are still refractory to treatment due to primary drug resistance. In recent years, the FLAG regimen consisting of fludarabine (Flud), arachidonic acid (Ara2 C) and granulocyte colony-stimulating factor (G2 CSF) has been used to treat refractory or relapsed AML with some success. We applied this regimen to treat 27 patients with refractory or relapsed AML, and initially evaluated the efficacy of this regimen.
The overall treatment response of AML patients to the FLAG regimen was 48.1%, but the CR rate was higher than that of AML patients. However, the CR rate was low, with only 7 patients (25.9%) achieving CR. CR was achieved in 7 cases (25.9%); PR was achieved in 6 cases (22.2%). There were 13 cases of NR and 1 case of early death. The median survival and DFS of those who achieved CR were 11.5 months and 6.5 months, respectively. The median survival and DFS of those who achieved CR were 11.5 months and 6.3 months, respectively. The median survival and DFS of those who achieved CR were 11.5 and 6.3 months, respectively, which were much longer than those who achieved PR and NR (median survival 5.5 and 4.5 months, respectively). 5 and 4 . The median survival was 11.5 and 6.3 months for PR and NR patients (median survival 5.5 and 4.5 months, respectively).
2 The efficacy of the FLAG regimen in different types of patients was highest in patients with late relapse, with 2 out of 5 cases (40 . However, the overall efficiency was lower than that of the early relapse and refractory groups; the early relapse group had the highest overall efficiency of 66 . The early relapse group had the highest overall efficiency of 66.7%, but the CR rate was the lowest among the three groups, with only 1 out of 6 cases (16.7%) having CR. The total CR rate in the primary refractory group (36.4%) was close to that of the late relapsed group. The overall CR rate in the primary refractory group (36.4%) was close to that of the late relapse group (40.0%), but the number of patients who achieved CR was only 1 (16.7%). The total CR rate in the primary refractory group (36.4%) was close to that in the late relapse group (40.0%), but all of those who achieved CR were primary AML, and none of the patients with MDS and CML had remission. A total of 4 patients (2 each with PR and CR) were treated with the second FLAG regimen, and 1 of the 2 PR patients achieved CR. Cytogenetic examination was performed in 25 patients, and the cytogenetic variants were found in the intermediate prognosis group (17 patients) with an overall efficiency of nearly 60 . The CR rate was 35.0%. The prognosis group (8 cases) was 25.0% and 12.0%, respectively. The prognosis group (8 cases) was 25.0% and 12.5%, respectively. In the poor prognosis group (8 cases), the overall efficiency and CR rate were 25.0% and 12.5%, respectively. 16 cases were tested for the drug resistance gene mdr1/P170), and the overall efficiency and CR rate of 7 patients with positive drug resistance gene were 43 . The total effective rate and CR rate of the 7 patients with positive resistance gene were 43.0% and 14.0% respectively. The CR rate was 55.5% and the PR rate was 11.5% in 9 patients with negative resistance gene. The CR rate was 55.5% and the PR rate was 11.1%. The total effective rate was 66.6%. The total effective rate was 66.6%.
Due to the presence of primary and secondary drug resistance, most patients with refractory relapsed leukemia have a poor prognosis. The main treatment is still a regimen of high-dose Ara2C combined with anthracyclines, but the efficacy is unsatisfactory, with a CR rate of only 16%-44% and a median DFS period of 5-9 months. The efficacy of the FLAG regimen for refractory and relapsed AML varied widely among authors, with CR rates ranging from 30% to 81%, mostly around 50%.
The role of FLAG in refractory and relapsed AML is clear, and although the long-term outcome is still unsatisfactory, it may at least provide an opportunity and time for patients who are ready for transplantation, as well as a treatment option for patients with poor prognosis.