Discussion
myeloid malignancy, toxicity, AML/MDS, GVHD, aGVHD
MINOR, REMISSION, EFFECTS OF CHEMOTHERAPY, GVHD, COMPLICATIONS
Chemotherapy followed by DLI is a promising treatment for relapsed AML/MDS after allo-HSCT. However, the effects of chemotherapy plus DLI are not ideal, and there are many complications. Therefore, we conducted a study using CCAG plus DLI regimen to achieve CR in patients who relapsed after allo-HSCT without causing unacceptable toxicity or GVHD. In this study, the CCAG plus DLI regimen demonstrated a CR of 45%, the 1-year OS of 56.7% (95% CI, 31.6–75.6%), the 1-year RFS of 83.3% (95% CI, 27.3–97.5%), and no treatment-related issues. To the best of our knowledge, this study represents the first prospective clinical trial evaluating the efficacy and safety of CCAG plus DLI regimen in relapsed AML/MDS after allo-HSCT.In 2004, S-J Choi et al. reported the results of a prospective study evaluating the efficacy of etoposide, cytarabine, idarubicin, and G-CSF followed by G-CSF-primed DLI in patients with advanced myeloid malignancy who relapsed after allo-HSCT [An attractive safety profile of CCAG plus DLI regimen, which showed tolerable and mostly reversible side effects, was also noted in our study. This promising outcome might have been a result of the low toxicity of the CAG regimen and the continuous use of G-CSF. Chemotherapy before DLI has been used for decades. However, most chemotherapy regimens are similar to the high-dose regimens used before transplantation, resulting in 20% TRM of relapsed patients after allo-HSCT in earlier reports [A significantly lower incidence of aGVHD was found in this study. There are several possible reasons for this result: (1) The CAG regimen has lower toxicity and causes minor organ damage; (2) Patients were given immunosuppressive agents to prevent aGVHD; (3) Chidamide might regulate the immune system, leading to less aGVHD. Although there are no studies exploring the effect of chidamide on GVHD, some relevant results can provide some clues. Zhao and his colleagues demonstrated that low-dose chidamide stimulated the production of natural Foxp3We further analyzed the factors related to CR/PR and OS and found much worse outcomes in patients who relapsed within less than 6 months after allo-HSCT. This result is in accordance with previous studies, in which early relapse heralded a dismal prognosis [This study has several limitations. First, our data should be interpreted cautiously considering the limited number of patients. Second, in this study, there was a male predominance of the population, which may have induced sampling bias and limit the applicability of the results to all patients. Some articles have shown that the treatment effect of chemotherapy and DLI in females is better than that in males [In conclusion, CCAG plus DLI regimen was feasible and effective in relapsed AML/MDS patients after allo-HSCT, especially in patients with a relatively long post-HSCT remission duration. A study with a larger cohort is needed to verify the results.