Acute myeloid leukemia (AML) is the second most common type of leukemia in children and accounts for up to 20 % of all leukemias. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective, and sometimes the only therapeutic option in high-risk patients with AML. Graft-versus-host disease (GVHD) is a major complication of allo-HSCT and the main cause of transplant-related mortality. GVHD prophylaxis in children includes calcineurin inhibitors, either alone or in combination with other immunosuppressants, which can lead to grade II–IV acute GVHD in 40–85 % of cases. Alternatively, GVHD can be prevented with high-dose cyclophosphamide (50 mg/kg/day) administered on days +3, +4 after allo-HSCT, either alone or in combination with other immunosuppressive drugs depending on HLA compatibility of the donor. The aim of this study was to evaluate outcomes after allo-HSCT from an unrelated donor with GVHD prophylaxis with post-transplant cyclophosphamide (PTC) in children in their first and second remission of AML in comparison with a historical control group. We retrospectively analyzed patient outcomes after 53 first-time allo-HSCTs from HLA-matched (n = 40) and partially-matched (8–9/10) (n = 13) unrelated donors performed in pediatric patients (aged 0 to 18 years) in their 1 st or 2 nd remission of AML at the R. M. Gorbacheva Research Institute for Pediatric Oncology, Hematology and Transplantation from 2008 to 2018. The study was approved by the Independent Ethics Committee and the Scientific Council of the I. P. Pavlov First Saint Petersburg State Medical University of Ministry of Healthcare of the Russian Federation. Our group of interest included 26 patients preventively treated for GVHD with 50 mg/kg of cyclophosphamide on days +3 and +4 in combination with calcineurin inhibitors (cyclosporin A – 2 (7.7 %) patients, tacrolimus – 24 (92.3 %) patients), the mTOR inhibitor sirolimus (5 (19.2 %) patients) or mycophenolate mofetil (21 (80.8 %) patients). The historical control group was made up of 27 patients whose GVHD prophylaxis was based on antithymocyte globulin used in combination with calcineurin inhibitors (tacrolimus – 5 (18.5 %) patients, cyclosporin A – 21 (77.8 %) patients) or the mTOR inhibitor sirolimus (1 (3.7 %) patients) or methotrexate (25 (92.6 %) patients), or mycophenolate mofetil (2 (7.4 %) patients). The groups were matched for diagnosis, age, disease status before allo-HSCT, the matched-to-partially-matched donor ratio, the source of hematopoietic stem cells and conditioning regimen intensity (myeloablative conditioning regimen (MAC) or reduced intensity conditioning regimen (RIC)). The median age at the time of allo-HSCT was 8.6 (0.97–18) years in the PTC group and 6.55 (1.42–17.76) years in the historical control group. In the PTC group, 21 (80.8 %) patients were diagnosed with primary AML and 5 (19.2 %) – with secondary AML, while the historical control group included 22 (81.5 %) and 5 (18.5 %) patients with primary and secondary AML respectively. Disease status at the time of allo-HSCT: 21 (80.8 %) patients treated with PTC were in the 1 st complete clinical and hematologic remission (CCHR) and 5 (19.2 %) – in the 2 nd CCHR; among the controls, there were 19 (70.4 %) cases of the 1 st CCHR and 8 (29.6 %) cases of the 2 nd CCHR. In the PTC group, 18 (69.2 %) patients underwent allo-HSCT from 10/10 fully HLA gene-matched donors and 8 (30.8 %) – from 9/10 HLA-matched donors. In the historical control group, 19 (70.4 %) patients had allo-HSCT from 10/10 fully HLA gene-matched donors, 4 (14.8 %) – from 9/10 matched donors, and 1 (3.7 %) – from an 8/10 matched donor. In the PTC group, MAC was used in 14 (53.8 %) patients, RIC – in 12 (46.2 %) patients. In the control group, MAC and RIC were used in 14 (51.9 %) and 13 (48.1 %) patients respectively. In the group treated with PTC, hematopoietic stem cells were derived from the bone marrow in 14 (53.8 %) patients, from the peripheral blood – in 12 (46.2 %) patients. In the historical group, bone marrow was used in 13 (48.1 %) patients and peripheral blood - in 14 patients (51.9 %). The median graft cellularity (CD34+ × 10 6 /kg) in the PTC group was 4.60 (1.7–10.9) × 10 6 /kg, in the historical group – 6.60 (1.0–13.2) × 10 6 /kg. The overall and relapse-free 5-year survival rates were higher in the PTC group than in the historical control group: 83.3 % (95 % confidence interval (CI) 60.9–93.5) vs 59.3 % (95 % CI 38.6–75.0), p = 0.0327 and 76.9 % (95 % CI 55.7–88.9) vs 48.1 % (95 % CI 28.7–65.2), respectively, p = 0.0198. The cumulative incidence of grade II–IV acute GVHD and grade III–IV acute GVHD by day +125 and of moderate and severe chronic GVHD, and the 2-year transplant-related mortality were significantly lower in the PTC group compared to the controls: 15.4 % (95 % CI 4.8–31.5) vs 51.8 % (95 % CI 31,9–68.5), p = 0.004; 7.7 % (95 % CI 1.3–21.7) vs 33.3 (95 % CI 16.8–50.9), p = 0.026; 23.4 % (95 % CI 9.5-41.0) vs 58.6 % (95 % CI 33.8–76.8), p = 0.022; 3.8 % (95 % CI 0.3–16.4) vs 25.9 % (95 % CI 11.5–43.1), p = 0.0232, respectively. GVHD-related mortality was higher in the historical control group than in the PTC group (3.8 % vs 18.5 %, p = 0.192). Thus, PTC-based GVHD prophylaxis was shown to be more effective in managing acute and chronic GVHD compared to antithymocyte globulin, with better overall, relapse-free and GVHD-free relapse-free survival rates and low transplant-related mortality.

Mucopolysaccharidosis type I (MPS IH; Hurler syndrome) is a hereditary storage disease caused by a deficiency of the lysosomal enzyme alpha-L-iduronidase. Enzyme replacement therapy may extend the lifespan of affected patients by 6–12 years but the only currently available radical treatment option is allogeneic hematopoietic stem cell transplantation (allo-HSCT). Objectives: We aim to evaluate the influence of conditioning regimens of various intensities and “graft versus host” disease (GvHD) prophylaxis with anti-thymocyte globulin and post-transplant Cyclophosphamide (PTCy) on overall (OS) and event-free (EFS) survival, the incidence of GvHD, the normalization of alpha-L-iduronidase and glycosaminoglycan (GAG) levels over time as well as cardiovascular and cognitive recovery following allo-HSCT. The study was approved by the Independent Ethics Committee and the Scientific Council of the I.P. Pavlov First Saint Petersburg State Medical University. We included 28 patients with MPS IH who had received allo-HSCT at the clinic at the R.М. Gorbacheva Memorial Institute of Children Oncology, Haematology and Transplantation. The five-year OS was 89%, the EFS – 57%. The use of myeloablative conditioning regimens and allo-HSCT within 12 months of diagnosis improve EFS in affected patients. The cumulative incidence of grade II–IV acute GvHD and grade III–IV acute GvHD was 43% and 18% respectively. The use of PTCy results in a significantly lower incidence of this complication (69% vs 33%, p = 0.013). After allo-HSCT, normal alpha-L-iduronidase levels and urinary GAG excretion were achieved in cases where graft function was normal. Allo-HSCT is an effective treatment for patients with MPS IH. Myeloablative conditioning regimens are the preferred treatment modality for this group of patients but in cases of comorbidities or poor physical status at the time of allo-HSCT, conditioning regimens with reduced intensity may be opted for instead. PTCy may be used for GVHD prevention in patients with MPS IH without increasing the risk of cardiac toxicity.

INTRODUCTION:Allogenic transplantation of hemopoetic stem cells (allo-THSC) is one of the most effective treatment methods for Hurler syndrome, aimed at maximal correction of complications related to the genetic disorder. Presence of infection in the recipient is an adverse risk factor, affecting the possibility of starting the conditioning regimen and THSC peforming in general.AIM:To assess the condition of the nasal cavity and paranasal sinuses in Hurler syndrome patients before the allo-THSC, dynamics of these changes after the transplantation taking into account the correction of alpha-L-iduronidase enzyme level with donor blood cells.MATERIAL AND METHODS:From February 2012 to December 2017, In the Raisa Gorbacheva Research Institute of Child Oncology, Hematology and Transplantology of the Pavlov First Saint Petersburg State Medical University, eighteen Hurler syndrome patients (10 girls and 8 boys) received an allo-THSC. Median age at the time of the procedure was 23,5 months (min - 3,4; max - 24,8). Each patient with the shadowing of paranasal sinuses, rhinitis or nasal breathing difficulty received a standard rhinosinusitis treatment before the transplantation, effect of which was insignificant. Symptoms of rhinitis, condition of pharyngeal tonsil and paranasal sinuses were assessed before and auto the allo-THSC.RESULTS:In the post-allo-THSC, with the correction of alpha-L-iduronidase level each evaluated parameter has improved reliably (p-value < 0,05). Comparative analysis of the condition of the nasal cavity and pharyngeal tonsil before and after THSC was conducted on 14 patients out of 18. Rhinitis symptoms decreased in 9 (64,2%) patients; in 11 patients (78,5%) adenoids size reduced. Comparative analysis of the condition of paranasal sinuses was possible in 12 patients out of 18. Sinuses aeration improved in eight (66,6%) if patients.CONCLUSION:Nasal cavity and paranasal sinuses changes in Hurler syndrome patients before and after allo-THSC is poorly studied. Our experience demonstrates the normalization of nasal cavity, pharyngeal tonsila and paranasal sinuses symptoms in the majority of the patients receiving allo-THSC. These symptoms are, it seems a consequence of the underlying disease.

Transplantation of allogeneic hematopoietic stem cells (allo-HSCT) is an effective treatment method for non-malignant diseases and inherited disorders. Development of acute GVHD is a negative factor for outcomes. Using «novel» strategies for drug prophylaxis, such as posttransplant cyclophosphamide (PtCy) allows to decrease the GVHD risk. The aim of this study: to assess efficiency of PtCy as a prophylaxis aGVHDin the patients with non-malignant diseases of hematopoiesis and inherited syndromes. 97 patients with non-malignant blood disorders and metabolic diseases received 118 underwent allo-HSCT at the R. Gorbacheva Memorial Institute of Children Oncology and Transplantation. The aGVHD prophylaxis in 89 cases was performed by a standard schedule (with calcineurin inhibitors). 29 patients were treated according to PtCy regimen, at a dose of 50 mg/kg at days +3, +4. Cumulative incidence (CI) of aGVHD comprised 32%. Patients treated with PtCy exhibited lower rates of this condition compared to the group with standard prophylaxis schedule (26 vs 47%, р = 0.05). CI of skin aGVHD was also less common in the PtCy group (23 vs 45%, р = 0.046); gastrointestinal aGVHD was observed at equal rates in the both groups. Stem cell engraftment after nonmyeloablative conditioning in HSCT patients with subsequent PtCy administration proved to be sufficiently weaker compared to other patients (86 vs 50%, р = 0.004). Conclusions: aGVHD prophylaxis based on posttransplant PtCy is an efficient method which may decrease aGVHD risk. However, one should take into account a higher non-engraftment rate as a potential hazard of HSCT when using non-myeloablative conditioning regimens and PtCy-based GVHD prophylaxis.

Haploidentical transplantation (Haplo-HSCT) is an effective method for treating patients with high-risk acute leukemias (AL) who do not have HLA-matched related (MRD) and matched unrelated donors (MUD). During 10 years in our centre more than 150 Haplo-HSCT were done. More than 50% of patients with resistant disease or resistant relapse – «salvage group» patients. 106 patients with high-risk AL, median age – 7 y.o. (range 0–18), acute lymphoblastic leukemia (ALL) – 63 (59,4%), acute myeloid leukemia (AML) – 43 (40,6%), received Haplo-HSCT from December 2006 till December 2016. Forty three patients (40,6%) recived Haplo-HSCT in complete remission (CR): CR1 21 (49%) patients, CR2 – 13 patients (30%), CR3 – 9 (21%). Resistance disease or resistance relapse AL – 63 (59,4%) patients. Сonditioning regimens were as follows: MAC «GIAC» – 39 (36,8%) patients, MAC based on Busulfan 12 mg/b.w. and Fludarabine 150 mg/mg (2) – 2 (2%), MAC reduced toxisity based on Treosulfan 42 g/m (2) – 6 (5,7%), RIC based on Melfalan 140 mg/m(2) – 40 (37,7%), RIC with Busulfan 8mg/b.w. – 18 (17%). All patients received prophylaxis of acute graft versus host disease (aGVHD). Seroprophylaxis with ATG – ATGAM 60 mg/b.w. – 39 (36,8%), posttransplant cyclophosphomide 50 mg/b.w. on D+3, D+4 – 67 (63,2%). Conventional immunosuppressive therapy: tacrolimus – 47 (44,3%) patients, CsA – 59 (55,7%). Source of transplant – combined unmanipulated stimulated Haplo-bone marrow plus manipulated (positive selected CD34+) stimulated CD34+ cells × 27 (25,5%) patients and unmanipulated stimulated Haplo-bone marrow – 79 (74,5%). Stem cells dose of unmanipulated stimulated Haplo-bone marrow transplant CD34+ × 10(6)/b.w. median – 5,9×10(6)/b.w., stem cells dose of combined transplant median 5,9×10 (6)/b.w. (range from 2,5 till 30,9×10(6)/b.w. Statistical analysis: SPSS Statistics v.17. Overal survival (OS) was defined as time from study enrollment to death, with living patients censored on the date of the last follow-up. The Kaplan–Meier method was used to estimate OS rates, and the exact log-rank test was used to compare survival curves. Survival estimate are reported with standard errors determined by the method of Peto and Pike.

Результаты аллогенной трансплантации гемопоэтических стволовых клеток от гаплоидентичного донора с применением неманипулированного трансплантата у детей и подростков, страдающих острыми лейкозами высокой группы риска: опыт 10 лет наблюдения

Treatment results of hematopoietic stem cells transplantation (HSCT) with myeloablative (MAC) and reduced intensity (RIC) conditioning regimen in children and adolescents with myelodysplastic syndrome (MDS). Fifty seven patients aged 1to18 years who received allo-HSCT from 1996 to 2016 (30 patients with MAC and 29 patients with RIC) are included in the study. Analysis of overall and event-free survival in both groups showed comparable efficacy. The use of RIC as alternative conditioning regimen in children and adolescents with MDS.

Aim. The aim was to evaluate the results of the allogeneic hematopoietic stem cells transplantation (allo-HSCT) in children and adults with the most prognostically unfavorable acute lymphoblastic leukemia (ALL) with t(4; 11)(q21; q23)/KMT2A-AFF1 translocation. Methods. We examined 21 patients (12 females, 9 males) aged from 3 months to 48 years (median 18.9 years). The analysis of prognostic factors of overall (OS) and eventfree survival (EFS) after allo-HSCT in patients of different age groups with various clinical, transplantation and cytogenetic characteristics was performed. Allo-HSCT from HLA-compatible related and unrelated donors, as well as haploidentical allo-HSCT were performed in 4, 9 and 8 patients of age groups < 1 year, 1-18 years, and >18 years, respectively. In 10 (48 %) patients, allo-HSCT was performed in the first remission, in 2 (10 %) patients in the second remission, and in 9 (43 %) patients during the disease relapse. Results. In 8 (38 %) patients, the only chromosomal disorder was the translocation t(4; 11)(q21; q23). Additional changes in chromosomes were found in 11 (52 %) patients. In 8 (38 %) of them, 3 or more chromosomal abnormalities in the karyotype were found. According to the results of a univariant analysis, the OS and EFS were significantly different in patients with allo-HSCT performed in the first remission and at other stages of ALL (in the second remission and in relapse: p < 0.001 in both cases), as well as in patients with or without 3 or more cytogenetic disorders in the karyotype (p = 0.04 in both cases). The multivariant analysis showed that the only independent prognostic factor affecting the OS and EFS in ALL patients with t(4; 11) was the allo-HSCT, including the haploidentical procedure, during the first complete hematological and molecular remission (p = 0.002 and p = 0.0004, respectively). Conclusion. ALL with t(4; 11)/KMT2A-AFF1 was as an absolute indication for allo-HSCT in first remission, including children of < 1 year age group. Satisfactory results can be obtained with the use of haploidentical transplantation from the parents. This approach eliminates the search in the registers completely HLA-compatible donor and facilitates the treatment procedure.

The only proven cure for Shwachman–Diamond syndrome (SDS) bone marrow failure is allogeneic hematopoietic stem cell transplantation (HSCT). However HSCT with donors other than HLA-identical siblings is associated with high mortality and unfavorable prognosis. This paper presents the first experience of HSCT treatment of SDS using an unaffected HLA-identical sibling produced through preimplantation genetic diagnosis (PGD). The patient was a 6-year-old blood transfusion-dependent SDS baby girl with secondary myelodysplastic syndrome, for whom no HLA-identical donor was available. As a result of PGD, two unaffected HLA matched embryos were identified; one of them was randomly selected for transfer, resulting in a clinical pregnancy and birth of an apparently healthy child. The patient underwent allogeneic transplantation of cord blood hematopoietic stem cells, together with bone marrow from this sibling, resulting in complete hemopoietic recovery. The patient was no longer transfusion-dependent and had normal blood values 160 days after transplantation.

Osteopetrosis is a group of rare hereditary diseases, the general structural manifestation of which is the excessive volume of bone tissue due to violation of osteoclastic resorption. The only way to treat this group of patients so far remains transplantation of hematopoietic stem cells, but the degree of its effectiveness largely depends on the severity of morphological changes in the hematopoietic microenvironment in the bone marrow. In this regard, a comprehensive clinical and morphological analysis, in conjunction with the results of transplantation can help in determining the prognosis of the disease depending on the genetic type of osteopetrosis. The material for the studies were biopsies and smears of bone marrow of patients with osteopetrosis, who were received at the R. Gorbacheva Memorial Research Institute for Pediatric Oncology, Hematology and Transplantation from the republics of Chuvashia and Mari El for carrying out transplantation of hematopoietic stem cells. The histological preparations were stained with hematoxylin and eosin, azur by Romanovsky and by Van Gieson. Bone marrow smears were stained by Romanovsky-Giemsa. The presence of the mutation c.807 + 5G>A in the gene TCIRG1 in patients with autosomal recessive osteopetrosis causes a complete loss of osteoclastic resorption, which is accompanied by pronounced early structural changes in the hematopoietic microenvironment already at the time of diagnosis. This is manifested by an excessive amount of lamellar bone at the same time as the almost complete obliteration of the medullar lacunae, as well as fibrosis of the bone marrow stroma. A common morphological phenomenon among this group of patients is the presence in the bone marrow of an excessive number of osteoclast differentiation cells without the formation of resorption lacunae. This causes a complete suppression of hemopoiesis, which clinically manifests cytopenia and the formation of foci of extramedullary hematopoiesis. Such pronounced structural changes in the hematopoietic microenvironment result in a high risk of primary graft failure during after transplantation of bone marrow hematopoietic stem cells, the effectiveness of which decreases as the child's age increases. Early development of pronounced structural changes in the hematopoietic microenvironment in patients with TCIRG1-mediated osteopetrosis determines the need for diagnosis and transplantation as soon as possible after birth.

Aim. To evaluate the impact of additional chromosomal aberrations on outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with acute myeloid leukemia (AML) with t(8;21)(q22;q22)/RUNX1-RUNX1T1 translocation. Methods. Twenty-five AML patients with t(8;21)(q22;q22)/RUNX1-RUNX1T1 translocation (10 women and 15 men, aged from 2 to 58 years; median 20.2) were examined. Analysis of overall (OS) and event-free survival (EFS) predictors after allo-HSCT in patients with different clinical, transplant and cytogenetic characteristics was performed. Results. The additional cytogenetic abnormalities were found in 13 (52 %) patients before the transplantation, at that, complex karyotype with three or more chromosomal abnormalities were registered in 9 (69 %) patients. The univariate analysis showed that OS and EFS after allo-HSCT differed in patients with different characteristics such as age (p = 0.03; p = 0.0006), clinical status at transplantation (p = 0.0002; p = 0,006), donor type (p = 0.0003; p = 0.002), the interval from diagnosis of leukemia to allo-HSCT (p = 0,008, for OS only), additional cytogenetic abnormalities (p = 0.03; p = 0.009) and complex karyotype (p = 0.004; p = 0.0003), respectively. In multivariate analysis, independent predictors of OS were donor type (p = 0.01), the interval from diagnosis of leukemia to allo-HSCT (p = 0.01), and additional cytogenetic abnormalities in karyotype (p = 0.04), as well as donor type (p = 0.04) and patient’s age (p = 0.004) for EFS. Conclusion. AML with t(8;21)(q22;q22)/RUNX1-RUNX1T1 translocation is a heterogeneous disease. The prognosis in patients with the additional cytogenetic abnormalities, especially in those with the complex karyotype, is worse both after the standard chemotherapy (i.e. before allo-HSCT), and after allo-HSCT.

Aim. To evaluate the prognostic impact of the different cytogenetic characteristics, including the modal number, the number of chromosomal aberrations in a complex karyotype, and adverse chromosomal abnormalities (ACA) (-7/7q-, -5/5q-, -17/17p-, t(6; 9)(p22; q34)) on the results of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with hyperdiploid acute myeloid leukemia (H-AML). Methods. Forty seven H-AML patients (21 women and 26 men, aged from 1 to 58 years, median - 23.9 years) were examined. The analysis of overall (OS) and event-free survival (EFS) predictors after allo-HSCT in patients with different clinical, transplant and cytogenetic characteristics was performed. Results. The modal number of chromosomes (MN) of 4748 was the most common one in the karyotype which was observed in 31 (66 %) patients. High hyperdiploidy with the modal number of 49-65 was identified in 13 (28 %) patients, near-triploid and near-tetraploid karyotypes were found in 3 (6 %) patients. Quantitative chromosomal abnormalities were nonrandom. Chromosome 8 (50 %), 21 (32 %), 13 (16 %) and 22 (16 %) trisomy was the most common one. Structural chromosomal abnormalities were detected in 22 (47 %) patients, at that, ACA were found in 7 (19 %) patients. In univariate analysis, the OS and EFS after allo-HSCT differed in patients with different clinical status (remission vs. active disease; p = 0.003 and p = 0.002, respectively), different chromosomal abnormalities in hyperdiploid karyotype (ACA- vs. ACA+; p = 0.001 and p = 0.03, respectively). An additional analysis of selected patients group with a structurally complex karyotype (n = 19) showed, that patients without ACA had a higher OS than patients with ACA (p = 0.03). In multivariate analysis, the disease status (relapse) at allo-HSCT was an independent predictor of decreased OS and EFS (p = 0.004 и p = 0.006, respectively), as well as the presence of the ACA (p = 0.002 only for OS). Conclusion. ACA were high-risk factors in H-AML patients received allo-HSCT. Therefore, the patients with formal criteria of a complex karyotype should not be automatically included in the cytogenetic unfavorable risk group.

Aim. To evaluate the prognostic significance of the complex karyotype including del(5q), -7, del(7q) abnormalities in acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Materials & Methods. Forty-four AML patients with chromosome 5 and/or 7 abnormalities (22 women and 22 men, aged from 1.2 to 67 years, median 31.2 years) were examined. Analysis of overall (OS) and event-free survival (EFS) predictors after allo-HSCT in patients with different clinical, transplant and cytogenetic characteristics was performed. Results. Prior to allo-HSCT, the complex karyotype (with three or more chromosomal abnormalities) was observed in 19 (43 %) patients, the monosomal karyotype was in 8 (18 %) patients. Univariate analysis demonstrated that OS and EFS differed in patients from different age groups (> 18 vs. < 18 years; p = 0.01 and p = 0.05, respectively), with different disease status at transplantation (1 remission vs. other clinical status; p = 0.1 and p = 0.008, respectively), with and without complex karyotype (СК- vs. CK+; p = 0.05 and p = 0.002, respectively), with and without monosomal karyotype (МК- vs. MK+; p = 0.009, only for EFS), and with different stem cells source (bone marrow vs. other source; p = 0.03 only for OS). Multivariate analysis confirmed that age of 18 years and more (p = 0.02 and p = 0.01, respectively), active disease at allo-HSCT (p = 0.04 and p = 0.005, respectively), complex karyotype (p = 0.04 и p = 0.0008, respectively) and stem cell source other than bone marrow (p = 0.02 only for OS) were independent predictors of OS and EFS deterioration. Conclusion. The study demonstrates that chromosome 5 and/or 7 abnormalities as a part of the complex karyotype is high-risk factor in AML patients undergoing allo-HSCT (unlike the monosomal karyotype), that requires the special therapeutic approach.

Selection of donor is the basis for success of allogeneic hematopoietic stem cell (HSC) transplantation (allo-HSCT). It needs to consider the individual characteristics of recipient and donor. The main of these are -disease, the HLA-matching, type of donor (related, unrelated), the source of HSC (BM, PBSC, umbilical cord blood). For haplo-HSCT particular importance are donor age below 30 years, male, NIMA incompatibility, NK-allo reactivity. Currently, for each patient, having indications for allo-HSCT, can be found allogeneic HSC donor. The following possibilities may be considered consequentially: a matched related donor; matched unrelated donor; partially matched unrelated donor (9/10 or 8/10); haploidentical donor; umbilical cord blood; matched sibling donor after in vitro fertilization – preimplantation genetic diagnosis.