[Effects of iron chelation therapy on allogeneic hematopoietic stem cell transplantation in myelodysplastic syndrome patients with iron overload].

OBJECTIVE:To investigate the effects of iron chelation therapy on hematopoietic reconstitution and related complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myelodysplastic syndrome (MDS). METHODS:Various clinical parameters were analyzed retrospectively in 57 MDS patients with iron overload who received allo-HSCT. According to the level of serum ferritin (SF) before transplantation divided patients into two groups: the effective treatment group (SF<1 000 μg/L) and iron overload group (SF≥1 000 μg/L). RESULTS:①30/57 cases were received iron chelation treatment, 27/57 patients didn' t received iron chelating therapy before transplantation. 19/30 cases were in the effective treatment group, and the median SF level before transplantation was 561 (223-846) μg/L. 11/30 cases were in the iron overload group, and the median SF level before transplantation was 1 262 (1 100-2 352) μg/L. The median SF level was 1 540 (1 320-3 112) μg/L of 27 patients didn't received iron chelating therapy before transplantation. ② The rate of fully-engraftment in the effective treatment group and iron overload group was 19 cases (100.0% ) and 34 cases (89.5% ), myeloid reconstitution of 12(10-18) and 12(11-30) days respectively (P=0.441), and platelet reconstitution of 13(12-30) and 15 (10-32) days respectively (P=0.579). ③The infection risk rate of the effective treatment group was less than iron overload group [36.8% (7/19) vs 82.4% (28/34), P=0.002]. ④The incidence of aGVHD in effective treatment group was less than iron overload group [26.3%(5/19) vs 64.7%(22/34), P= 0.010]. All patients of the effective treatment group were Ⅰ/Ⅱ degree. 16 cases were Ⅰ/Ⅱ degree and 6 cases were Ⅲ/Ⅳ degree in the iron overload group. ⑤ 6 cases of iron overload group accepted iron chelation treatment early post-transplantation, and SF level decreased from 2 870 (2 205-3 580) μg/L to 1 270 (1 020-1 650) μg/L. ⑥The difference of median disease-free survival time between the effective treatment group and iron overload group was not statistically significant [28.9 (0.3-89.5) months vs 21.2(0.1-81.0) months, χ(2)=3.751, P=0.053]. CONCLUSIONS:Iron overload obviously increased transplant-related complications, and effective iron chelation therapy before transplantation significantly decreased the incidence of infection and degree of aGVHD, thereby reduced the non-relapse mortality in patients with MDS.