Introduction. Minor histocompatibility antigens (MiHAs) — polymorphic peptides presented in HLA molecules that are products of genes containing nonsynonymous single nucleotide polymorphisms. In allogeneic hematopoietic stem cell transplantation (allo-HSCT), the immune response directed to MiHA can result both in graft-versus-host and graft-versus-tumor responses.

Some MiHAs are promising and safe targets for T-cell immunotherapy of leukemia relapse after allo-HSCT.

Aim — to analyze the literature describing the immune response to various MiHAs, as well as clinical trials using MiHAs as targets of immunotherapy.

Main findings. MiHAs represent promising targets for the prevention or therapy of leukemia relapse after allo-HSCT due to their advantages over tumor-associated antigens and neoantigens. To be suitable for immunotherapy, MiHA must satisfy several parameters: 1) be presented by a common HLA allele, 2) have an optimal frequency of polymorphism-encoding allele, 3) be encoded by a gene that is predominantly expressed in hematopoietic tissue. This drastically limits the number of applicable targets and makes the discovery of new MiHAs highly relevant.

Introduction. Therapy of chronic myeloid leukemia (CML) for the majority of patients is associated with continuous lifelong drug intake. Irregular drug intake greatly increases the risk of CML progression and death. It is still not well understood to what extent social and demographic factors infl uence the long-term consequences of CML therapy.

Aim — to determine the prognostic value of social parameters like marital status and education level in comparison with standard risk factors for the course of the disease.

Materials and methods. A multifactorial data analysis of the presented sociodemographic parameters was carried out on a cohort of CML patients included in the multicenter observational study “Russian Registry for the Treatment of Chronic Myeloid Leukemia in Routine Clinical Practice”. The database of the study conducted in Russia in 2011–2016 includes records of 12160 patients with CML. To analyze the register data, we used classical methods of event analysis implemented in the SAS 9.4 package.

Results. A large volume of data with a high level of significance showed that educational level and marital status have a great prognostic value in assessing the long-term results of therapy in patients with CML, comparable to known risk factors. The contribution of these signs was evaluated and analyzed taking into account such known factors as age, ELTS index, and region or clinic where the patient was observed and treated. Thus, low educational qualifications and marital status “divorced” or “widowed” demonstrated significant and independent risk factors that negatively affect the life expectancy of patients with CML Conclusion. The discovered phenomenon is key in long-term survival and can be explained by the indirect infl uence of social-demographic parameters through adherence behavior of CML patients. Higher level of education proved to be a favorable factor while a widowed/divorced marital status was found to be an unfavorable factor of OS prognosis. General clinic, age related interpretations, and regional features were also tested and did not find any confirmation.

Introduction. Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia. Splenectomy is one the most effective treatment methods for this disorder.

Aim — to evaluate the effi cacy and safety of a splenectomy in patients with primary immune thrombocytopenia.

Subjects and methods. 111 patients (31 males, 80 females) with primary immune thrombocytopenia who were hospitalized to perform laparoscopic splenectomy were included in a prospective study conducted at the National Research Center for Hematology from 2015 to 2019. Disease duration from onset to splenectomy was from 1 month to 51 years. Response to the splenectomy, complications, and correlation with immediate preoperative platelet count were analyzed.

Results. Complete response was achieved in 79 (71.2 %) cases, a partial response was achieved in 11 (9.9 %) cases, and in 21 (18.9 %) cases there was no response. Immediate preoperative platelet count was signifi cantly higher in patients with complete response in comparison with the group with no response, median (95% CI): 47 (35–58) vs 16 (9–20), p < 0.001.

Multivariate analysis (logistic regression) was performed. According to this regression, a risk factor for an unfavorable response was detected — males > 60 years of age, p = 0.05; RR (95% CI): 2.0 (0.9–7.1). A predictor of unfavorable response was identifi ed – immediate preoperative platelet count < 23 × 109/l (cutoff point determined in ROC-analysis); p = 0.001, RR (95% CI): 2.5 (1.1–8.6). The probability of complete response was lower with the number of treatment lines prior to splenectomy (weak inverse correlation: r S = −0.30; p = 0.01). The frequency of postoperative complications was 12.6 %. According to our follow-up data, a complete response was preserved in 66/79 (83.5 %) of patients, with a follow-up of 2.7 years.

Conclusion. Splenectomy is an effective and safe treatment method for ITP. Factors of unfavorable response were identifi ed: males > 60 years of age and immediate preoperative platelet count < 23 × 109/l. It is safe to perform splenectomy regardless of effectiveness of preoperative splenectomy treatment and platelet count.

Introduction. Despite the success of current therapeutic approaches and suffi cient supply of clotting factor concentrates, adult patients with hemophilia have a high frequency of developing joint pathologies. Furthermore, an increase in life expectancy has correlated with an increase in the share of patients with concomitant somatic diseases, which are characteristic for this population over the age of 40 years.

Aim — to analyze the treatment results of adults with hemophilia living in the city of Novosibirsk and Novosibirsk region and evaluate their orthopedic status, types, frequency of bleeding, and comorbidity structure.

Material and methods. A total of 93 patients were enrolled in the study (including 86 patients with hemophilia A and seven patents with hemophilia B). The analysis was carried out separately in subgroups of patients according to age: 18–24, 25–34, 45–44, and over 45 years old. Hemophilia type, severity of disease, strategy of therapy, inhibitor status, and features of concomitant pathology were analyzed.

Results. A high frequency of spontaneous bleeding was found in all age groups of patients enrolled in the study (39.6 and 34.9 % during 6 and 12 months, respectively). The average frequency of joint bleeding was 4 cases per person per year in the group of patients aged ≥ 18 years.

In evaluation of orthopedic status, it was remarkable that there was a signifi cant number of target joints (262, n = 93), which amounted to 2.8 defected joints per patient (the elbow, knee, and ankle joints were the most frequently involved in pathological process). All patients aged over 18 years with severe and moderate form of disease had a musculoskeletal complication with involvement of one or more target joints.

The number of diseases per one patient prevailed in the age group over 45 years old and amounted to 4.12 comorbidities per patient. The prevalent diseases in the structure of concomitant pathology in adult patients with hemophilia were chronic viral hepatitis C (43.1 %, n = 42), stage I–III arterial hypertension (27.9 %, n = 26), stomach and duodenum diseases as well as gallbladder pathology (33.3 %, n = 31 and 26.9 %, n = 25, respectively), urolithiasis and chronic secondary pyelonephritis (21.5 %, n = 20).

Conclusion. Despite the use of clotting factor concentrates in patients with severe and moderate hemophilia, the frequency of joint hemorrhages remains high, regardless of the age prophylactic replacement therapy was started. Additional measures must be taken to prevent the appearance of critical disease phenotype with frequent spontaneous bleeding.

Introduction. The mechanism of action of extracorporeal photopheresis (ECP) is associated with the induction of apoptosis of lymphocytes, which cause the activation of antigen-presenting cells (APC). As a result of the use of ECF, the number of T-regulatory lymphocytes increases, which induces an immunosuppressive effect. The actual problem lies in the use of cryopreserved and photo-irradiated mononuclear cells.

Aim — to analyze the functional features of cryopreserved mononuclear cells after ECP.

Materials and methods. The study analyzed the indicators of early and late stages of apoptosis in the concentrate of mononuclear cells of different groups, depending on the time of collection and the type of exposure on these concentrates of mononuclear cells: immediately after apheresis (groups 1.1 and 1.2), and after ECP (groups 1.3, 2.1 and 2.2), groups 1.2 and 2.2 were after cryopreservation, and 1.3 — after cryopreservation, and then after ECP. 113 samples of mononuclear cell concentrates obtained from 12 patients with chronic graft-versus-host reaction (GVHD) were analyzed. All groups of samples were cultured to determine the dynamics of changes in indicators of early and late stages of apoptosis over time.

Results. The proportion of lymphocytes in the late stage of apoptosis after 2 days cultivation, after the standard ECP procedure, was comparable to the proportion of lymphocytes in the late stage of apoptosis during ECP followed by cryopreservation of the leukoconcentrate.

Conclusion. It is advisable to collect mononuclear cells, perform their extracorporeal photo-irradiation, and then divide the photo-irradiated mononuclear cells into several parts both for cryopreservation and for the return of non-cryopreserved photo-irradiated mononuclear cells to the patient.

Introduction. Generating manifold publications over decades, research continues assessing the burden of perioperative bleeding, preoperative anaemia and red blood component (RBC) transfusion in cardiac surgical patients. The past decade is witnessing a trend towards limited RBC transfusion. Nevertheless, the risk and justification of a restrictive or liberal transfusion strategy in cardiac surgery remain a matter of debate.

Aim — a description of evidence estimating the impact of bleeding, preoperative anaemia, red-cell transfusion and restrictive vs. liberal strategies on the risk of mortality and other adverse events in adults with cardiac surgery.

Methods. Relevant evidence was mined in PubMed for the period 2012–2019. The query phrases were: cardiac surgery [кардиохирургия], bleeding [кровотечение], preoperative anaemia [предоперационная анемия], red-cell transfusion [переливание эритроцитов], restrictive and liberal transfusion strategy [рестриктивная и либеральная трансфузионная стратегия]. The review includes 18 studies describing outcomes related to bleeding, preoperative anaemia of varying severity and variant-volume RBC transfusion in patients with cardiac surgery. Nine studies comparatively assessed the cardiac surgical clinical outcomes under restrictive and liberal transfusion strategies. A total of 24 full texts have been analysed, one randomised clinical trial (RCT) summary, one retrospective trial summary and one meta-analysis review. Additional studies of concern to discussion have also been considered.

Results. One prospective and four retrospective studies evaluated the effect of perioperative bleeding on the risk of subsequent adverse events in patients with cardiac surgery. Three prospective, five retrospective studies and one RCT revealed the association of red-cell transfusion with adverse outcomes. Five retrospective studies exposed a link between preoperative anaemia and reason for RBC transfusions. Six retrospective studies found an independent association between the risk of postoperative complications and mortality in patients having cardiac surgery and preoperative anaemia. Eight RCTs and one meta-analysis of seven RCTs presented comparative data on clinical outcomes of restrictive and liberal transfusion strategies in patients after heart surgery.

Conclusion. Preoperative anaemia, haemorrhage and donated component transfusion independently contribute to the risk of serious postoperative complications and death unifying in the “deadly triad” of cardiac surgery. RBC transfusions are integrally indicative of the aid quality in cardiac surgery reflecting the success of blood management system in the hospital. Leveraging a good patient blood management practice at all treatment steps to involve a multispecialty blood-team approach can significantly improve patient outcomes at a higher cost efficiency.

Introduction. The study of the possible impact of the blood group system ABO and other antigenic systems of red blood cells for cancer patients is currently directed at a number of distinct paths, including the study of changes in the expression of a group of antigens in tumors; the appearance of new antigens on tumor cells; the risk of developing tumors depending on the blood group; the possible infl uence of blood group on the prognosis of the disease, etc.

Aim — to examine the current state of the problem of the relationship between blood groups and cancer.

Main findings. There is evidence that cancer is less common in people with blood type O than in people with other blood groups of the ABO system. According to other data, this dependence is noted only for some types of cancer. In general, the results of work on this topic can be assessed as insuffi cient and sometimes contradictory.

Introduction. Some patients with chronic myeloid leukemia (CML) have cytogenetically variant forms of translocation that lead to the formation of the coalesced BCR-ABL gene. The adverse course and progression of the disease are often accompanied by the appearance of additional chromosomal abnormalities in the karyotype of the patient.

Aim — to describe a clinical observation of CML that occurred with the simultaneous presence of a variant translocation and a unique additional rearrangement in the patient’s karyotype.

Main findings. A conventional cytogenetic analysis performed in a patient with primary immune thrombocytopenia and subsequently developed chronic myeloid leukemia revealed a variant translocation t(X;9;22)(q28;q34;q11.2), as well as an additional chromosomal anomaly t(1;8)(q23;q24.1). The presented case of observation shows that a standard cytogenetic study is an important part of the examination of patients with hematological pathologies, since it allows identifying chromosomal changes that have diagnostic and prognostic signifi cance.

Introduction. Kaposi’s sarcoma (КS) is a multi-focal malignant tumor of vascular origin with a predominant lesion of the skin, involving internal organs and lymph nodes. Epidemic and immunosuppressive variants of the disease are considered to be the most studied and common. The main reason for the development of the immunosuppressive variant is the use of immunosuppressive drugs in patients after transplantation of solid organs. Descriptions of the development of Kaposi’s sarcoma in patients with diseases of the hematopoietic system are rare.

Aim — to describe a rare combination of a malignant tumor of vascular origin (Kaposi’s sarcoma) and a chronic myeloproliferative disease: primary myelofibrosis.

Main findings. To verify the diagnosis of Kaposi’s sarcoma in a patient with primary myelofibrosis, the following were used: histological, immunohistochemical studies of skin biopsies and the polymerase chain reaction method with detection of a fl uorescent signal in “real time” in biological material samples (peripheral blood, smear from the mucous membrane of the oropharynx, skin biopsies from lesions) with quantitative determination of the activity of the human herpes virus 8. A comprehensive examination made it possible to establish the final diagnosis of multiple malignant neoplasms and recommend treatment.

Introduction. Large B-cell lymphoma with IRF4 rearrangement is rare disease, recently described in WHO 2017, arising in children and young adults, presenting with enlarged lymph nodes of the head and neck and/or Waldeyer ring. It is characterized by strong expression of MUM1 protein with IRF4 rearrangement.

Aim — to present a clinical case of large B-cell lymphoma with IRF4 rearrangement and characterize its clinical, morphological, and cytogenetic features.

Main findings. An observation of a patient with a rare case of large B-cell lymphoma with IRF4 rearrangement is presented.

In-depth morphological, immunohistochemical analysis, and additional research methods made it possible to establish a correct diagnosis. Features of the case were the predominantly diffuse growth of large tumor cells in the lymph node biopsy with the indolent clinical course, and the presence of aberrations in both homologues of chromosome 6: IRF4 rearrangement and deletion 6p25. Treatment with 4 R-CHOP-21 courses allowed for the achievement of disease remission, which continued 26 months post treatment.

Introduction. The COVID-19 pandemic has led to the need to accelerate the development of vaccines targeting SARSCoV-2. A large number of researchers have already confi rmed that patients with cancer have a high risk of mortality from COVID-19. Hematologic diseases and the therapy of these diseases are very heterogeneous, therefore it is expected that the immune response to infection or vaccination will be more variable in this cohort of patients. Accordingly, questions arise regarding the safety and effi cacy of vaccines in the context of immune changes caused either by the hematological disease itself or by the therapy that is administered to the patient.
Aim — to summarize the current understanding of the effi cacy and safety of vaccination against the SARS-CoV-2 in patients with hemoblastosis and other hematological diseases.
Basic information. Legalized COVID-19 vaccines are safe and effective for the general population. Given the high mortality rate among patients with hematological diseases, which is ten times higher than the mortality rate in the general population, vaccination is a priority for this group of patients. The current lack of clinical trial data on the effectiveness and safety of vaccines against COVID-19 in hematological patients raises a large number of questions among specialists and patients. This is also due to the fact that for most of the approved vaccines immunocompromised patients were not included in the phase III clinical trials. Thus, most patients with hematological diseases could not participate in these studies, and therefore the effectiveness and safety of vaccines against the causative agent of COVID-19 have not been thoroughly studied in this group.
Current recommendations for vaccination against COVID-19 in hematological patients are based on expert opinion, including past experience of immunizing these patients against other viral infections.
Conclusions. Vaccination of patients with hematological diseases and their environment (medical staff, relatives, caregivers) is one of the necessary methods to prevent high mortality from a new coronavirus infection during the COVID-19 pandemic.