MICROTRANSPLANTATION OF HAPLOIDENTIAL HEMOPOETIC STEM CELLS OF PERIPHERAL BLOOD IN ACUTE MYELOID LEUKEMIA
Allogeneic hematopoietic stem cells transplantation after nonmyeloablative conditioning with transient microchimerism - microtransplantation (microHSCT) - is one of the new therapeutic approaches in the high risk group of transplant mortality in acute myeloid leukemia. Aim. Estimation of the role of microHSCTin the treatment older AML patients. Materials and methods. MicroHSCT was performed in 33 patients aged 55-75 years (median 64 years) with AML in the first (n23, 70 %) or second remission (n10, 30 %). There were 21 patients over 60 years old, 12 patients 55 to 60 years old. The median follow-up was 21 months (4-64 months). The control group was: 21 patients aged 55-67 years who received chemotherapy (CT), median age 59 years; 21 patients aged 55-70 years who received alloHSCT from an HLA-matched donor in the first or second remission, the median age was 58 years. Results. Two-year overall survival (OS) after alloHSCT was 66 % (95 % CI 46-86), 42 % (95 % CI 20-64) (median 31 months) after microHSCT, and 23 % (95 % CI 3-43) (median 17 months) at CT (p = 0.05). 2-year disease-free survival after alloHSCT was 65 % (95 % CI 46-84), 35 % (95 % CI 16-54) (median 18 months) after microHSCT, and 19 % (95 % CI 1-38) (median 12, 4 months) with CT (p = 0.05). There were no deaths associated with microHSCT. Two patients died from complications of alloHSCT, one as a result of a heart attack, the other from infectious complications associated with severe GVHD. During CT, 1 patient died from acute cardiovascular failure, the second from sepsis. Conclusion. OS after alloHSCT is higher than after microHSCT, however, if there are contraindications for performing alloHSCT in older patients, microHSCT can be considered as an effective and safe alternative to CT.