Early Hematopoietic Reconstitution Status after Haploidentical Transplantation in AML Patients Is Indicative of Early Complications

Objective

To investigate the early hematopoietic reconstruction process of haploidentical allogeneic hematopoietic stem cell transplantation (haplo-allo-HSCT) in patients with acute myeloid leukemia, and to explore its correlation with the occurrence of early complications after transplantation.

Methods

A retrospective analysis was performed on the clinical information of 187 AML patients who underwent haploidentical allo-HSCT at the Hematology Hospital of the Chinese Academy of Medical Sciences from January 2017 to December 2022, and all of these patients achieved complete remission before transplantation. The results of pre-transplantation-7d-after-tranplantation+14d blood routine were analyzed. The occurrence of aGVHD within 100 days after transplantation was the primary outcome event, and CMV infection within 60 days was the secondary outcome event. The diagnosis and grading of aGVHD is described in Glucksberg and MAGIC. R-4.2.0 statistical software was used for statistical analysis.

Results

A total of 187 AML patients who underwent haploid transplantation after achieving complete remission were included, with a median age of 35 (27-55) years, including 105 male patients (56.31%) and 82 female patients (43.69%). All patients were grouped into aGVHD patients according to different risk levels: (1) There were differences between the I~IV°aGVHD group and the patients without aGHVD (100 versus 87 patients) in the early post-transplantation plt and WBC absolute levels, and the I~IV°aGVHD group showed a lower plt trend in 1d and 2d, and a higher WBC level (0.08×10 ⁹/L vs 0.07×10 ⁹/L, p=0.036) at 10 days. (2) Compared with patients without aGHVD (70 versus 87 cases), the former showed lower plt levels (62.5×10 ⁹/L vs 80×10 ⁹/L, p=0.029) in 1d and higher WBC levels (0.03×10 ⁹/L vs 0.02×10 ⁹/L, p=0.047; 0.11×10 ⁹/L vs 0.07×10 ⁹/L, p=0.033) in 9d~10d), the Hb level was lower at 1d~3d (91g/L vs 99g/L, p=0.047; 91g/L vs 97.5g×109/L, p=0.039; 89.5g/L vs 95.5g/L, p=0.013). (3) Compared with patients without aGHVD (33 versus 87 patients), the III~IV°aGVHD group showed lower plt levels (60×10 ⁹/L vs 74×10 ⁹/L, p=0.006; 48×10 ⁹/L vs 52×10 ⁹/L, p=0.018; 26×10 ⁹/L vs 36.5×10 ⁹/L, p=0.003) in 1~3d, and high WBC level (0.04×10 ⁹/L vs 0.02×10 ⁹/L, p=0.025; 0.14×10 ⁹/L vs 0.07×10 ⁹/L, p=0.008) showed in 10 days, and lower Hb level in 1d~3d (89g/L vs 99g/L, p=0.047; 89g/L vs 97.5g/L, p=0.039; 83g/L vs 95.5g/L, p=0.013). Based on the maintenance of platelets at 20×109/L for 3 days after transplantation, the cumulative incidence of 100 days III~IV°aGVHD in the ≤3d group was higher (63% vs 30%, p=0.015). Univariate analysis showed that the absolute value of 1~3d plt after transplantation was low, and the PLT maintained at 20×10 ⁹/L after HSCT was short, which was a risk factor for the occurrence of aGVHD.

Group analysis of CMV occurring within 60 days showed that in the early post-transplantation period, patients in the non-CMV group had higher absolute platelet values (63.50×10 ⁹/L vs 47.00×10 ⁹/L, p=0.03) than patients in the CMV group at 0 days. Age, pretreatment regimen, transplant type, aGVHD prevention regimen, time to first PLT infusion after transplantation, absolute value of 0 d platelets, and platelet transfusion efficiency were included in univariate and multivariate analysis, and multivariate analysis showed that pretreatment regimen (p=0.017, 1.002 [0.606-0.953]) and transplant type (p<0.001, 0.264 [0.147-0.476]) were independent risk factors affecting the occurrence of CMV. No correlation between platelet transfusion efficiency and PLT infusion frequency and CMV was found.

Conclusion

Early hematopoietic reconstruction after transplantation in AML-CR patients who received haploid transplantation has certain indicative significance for the occurrence of early complications, and its indicative significance becomes more significant with the increase of aGHVD degree.