AIM: to work out an algorithm for diagnosis and tactics of treatment of complicated perianal abscess (CPA) in oncohematology. PATIENTS AND METHODS: the cohort study (January 2021 — December 2022) included 78 patients with hematologic malignancies and infectious lesions of the perianal soft tissues. Complex perianal infection (CPI) was distinguished in the presence of supralevator abscess, pelvic phlegmon, destruction of the rectal wall above the level of the dentate line, and pelvic organs involvement. The correspondence of clinical, laboratory data and MRI results, as well as the results of surgical drainage, antibacterial therapy, and vacuum therapy were assessed. RESULTS: CPI was detected in 7 (8.97%) patients with perianal infection. The neutropenia was detected in all patients (neutrophils < 500 × 10 9 /l); no fever occurred in two patients. Clinical data were adjusted after MRI results in 6 (85.7%) cases. Pelviorectal abscesses were noted in 5 patients, in 2 — pelvic phlegmon was detected. In addition, 2 patients revealed perforation of the rectum above the dentate line, 1 — rectovaginal fistula. Due to sepsis, 4 (57.14%) patients were in the intensive care unit, the period in the intensive care unit was 32.5 (17–54) days. Abscess drainage was performed in all patients, in 3 cases — diverting sigmostomy. The wound repair phase was achieved in all patients. The time of reparation was 79 (37–142) days. Vacuum therapy was used in 2 cases with wound repair time of 53.5 days. Postoperatively, febrile fever with periods of normothermia for 1 month was revealed in all cases. Two patients died within 50 and 215 days from causes unrelated to perianal abscess. CONCLUSION: pelvic MRI is a preferable diagnostic test to determine the volume of lesion in CPI in patients with hematological malignancies. CPI in patients with neutropenia is associated with a high incidence of sepsis. The main methods of infection control are abscess drainage and antibacterial therapy, which should be started before surgery and continued in the postoperative period until normothermia and regression of local signs of inflammation. Vacuum therapy is a safe and effective method in treatment of big postoperative wounds in patients with neutropenia.

Introduction. Acquired hemophilia is a rare autoimmune disease caused by an inhibitor to clotting factor VIII (FVIII). It complicates the course of many diseases, in particular autoimmune diseases, and in women is often associated with pregnancy. Aim — to present a case of successful treatment of a patient with acquired hemophilia using long-term continuous infusion of rFVIIa and inhibitor eradication as a result of immunosuppressive therapy. Main findings. A clinical observation of severe hemorrhagic syndrome in a patient with acquired hemophilia associated with pregnancy is presented. Uterine bleeding in the patient after spontaneous delivery, refractory to standard hemorrhagic syndrome treatment, required multiple surgical interventions. Laboratory tests showed prolongation of APTT, CT in the INTEM rotational thromboelastometry test, a decrease in plasma FVIII activity and presence of inhibitor to FVIII. Vacuum-assisted closure was applied to treat infected laparotomy wound. Therapy for acquired hemophilia consisted of hemostatic therapy and the inhibitor eradication. Hemostatic therapy included a continuous infusion of rFVIIa at a rate of 30 μg/kg/h with a gradual decrease up to 9.6 μg/kg/h, as well as its fractional administration before every surgery at a dosage of 80 μg/kg. The effectiveness of the therapy was assessed by the dynamics of CT in the INTEM test and the shortening of the APTT. The inhibitor eradication was achieved by prednisolone therapy, combined immunosuppression with rituximab and azathioprine, followed by its replacement with cyclophosphamide. As a result, the hemorrhage was stopped, reference plasma activity of FVIII and eradication of the inhibitor were reached.

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.

Background . Splenic marginal zone lymphoma (SMZL) is an indolent non-Hodgkin’s B-cell lymphoma. It presents morphologically by mature lymphoid B-cells. They conform to these immunological characteristics of marginal zone lymphocytes from secondary follicles. The tumor B-cells of SMZL do not have specific markers of immunophenotype and requires the exclusion of other non-Hodgkin’s B-cell lymphomas. There is an annual increase in the incidence of SMZL. There are refractory forms and progressive course of the SMZL. There is a huge variety of the mechanisms of evading tumor cells from immunological control. Unlike solid tumors, B-lymphoproliferative diseases are characterized by the expression of HLA I/II and co-stimulatory molecules (CD80 and CD86). Therefore, tumor B-lymphocytes can act as antigen-presenting cells (APC) for T lymphocytes. The T-cell immune response is known to play an important role in antitumor control. It is known that effective activation of T-lymphocytes requires the formation of an immunological synapse and the presence of two activation signals (antigen recognition and co-stimulation of CD28-CD80/86). According to the modern concept of tumor development, there is a gradual selection of tumor clones. As a result, only tumor cells that are invisible to the immune system remain. Mechanisms of evasion of tumor B-cells of SMZL from immune surveillance are currently not fully understood and are being actively studied. Objective : to study the expression features of antigens involved in the formation of immunological synapse in patients with SMZL in peripheral blood. Materials and methods . The study includes 10 primary SMZL patients; all patients have stage IV according to the Ann Arbor classification. Splenectomy was performed for all patients as a first stage of treatment. Two patients had progression of SMZL after splenectomy, which required chemotherapy. The control group included 25 healthy donors. Peripheral blood was used as a material for analysis. The study was conducted on a 6-color BD FACS Canto II flow cytometer (BD Biosciences, USA) immediately after diagnosis. Results . Tumor B-cells of SMZL are different from B-cells of healthy donors with a greater proportion of CD80 + , FAS + , PD-1 + -cells, which may correspond to activated B-cells. The proportion of CD4+PD-1+ and CD8 + PD-1 + T-cells in patients with SMZL was higher in comparison with the control group. There was a large proportion of T-cells expressing PD-1 in the group of patients with SMZL progression after splenectomy in comparison with the group of patients with indolent course of SMZL. Conclusion. Thereby, tumor B-cells of the SMZL retains the features of non-tumor analogues. The most significant mechanism for evading immune surveillance in an SMZL is inhibition of the T-cell immunity via the PD-1–PD-L1 pathway. The most pronounced inhibition of T-cell immunity causes an uncontrolled tumor process.

Background: Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia. Splenectomy remains an effective and safe treatment for ITP. Objective: Identify and estimate risk factors associated with no response (platelet count < 30 x 109/L) to splenectomy for adult ITP patients. Patients and Methods: The study conducted at National Research Center for Hematology (Moscow) from 03/2015 to 11/2019 included all patients (in total, 111) with ITP, who underwent laparoscopic splenectomy. Median (Med) platelet count at admission was 12 x 109/L (range from 1 to 239 x 109/L). The time from diagnosis of ITP to splenectomy varied from 3 months to 51 years. All patients had received from 1 to 3 lines of treatment prior to splenectomy. Pre-splenectomy treatment was carried out at platelet count < 20 x 109/L and/or in the presence of bleeding. Results: Of the 111 patients 31 were male (Med age 43 years [IQR 27-55]) and 80 were female (Med age 37 [IQR 29-49]). The male/female ratio was 1:2.6. Complete response to splenectomy (platelet count > 100 x 109/L) was achieved in 79/111 (71.2%) cases, 11/111 (9.9%) patients had partial response (platelet count: 30-100 x 109/L) and 21/111 (18.9%) failed to respond (platelet count < 30 x 109/L). Patients who achieved complete response to splenectomy had a significantly higher immediate pre-splenectomy platelet count than non-responders: Med platelet count (95% CI): 47 (35-58) vs 16 (9-20) (x 109/L), Mann-Whitney U test, P < 0.001 (CI, confidence interval) (Figure 1). Multivariate logistic regression analysis was carried out to identify factors associated with splenectomy outcome (response/no response). Multivariate analysis included patient's gender and age, duration of ITP, grade of bleeding at admission, platelet count at admission, preoperative platelet count and number of prior lines of therapy. Continuous variables were dichotomized using ROC analysis, in particular, cut-off point for preoperative platelet count was 23 x 109/L. As a result, following statistically significant (Wald test) factors were selected: • an unfavorable predictor: immediate pre-splenectomy platelet count < 23 x 109/L, RR (95% CI): 2.5 (1.1-8.6), P = 0.001 (RR, relative risk) (Figure 1) and • combined unfavorable risk factor: male gender in the age over 60 (compared to men in the age ≤60 and women in general), RR (95% CI): 2.0 (0.9-7.1), P = 0.05 (Figure 2). Response rate was negatively correlated (in univariate analysis) with the number of treatment lines prior to splenectomy (negative Spearman's rank correlation coefficient, −0.30; P = 0.01). When preoperative platelet count ≥ 23 x 109/L was achieved, probability of complete response to splenectomy was 80% (Figure 3). The rate of postoperative complications was 12.6%. According to our follow-up data (up to 5 years) 66/79 (83.5%) patients maintained complete response. Conclusions: High-risk groups were identified: patients with immediate pre-splenectomy platelet count < 23 x 109/L (i.e. with no effect of preoperative treatment) and men over the age of 60. Identified risk factors could be taken into account in decision-making process. Disclosures No relevant conflicts of interest to declare.

Background. Splenic marginal zone lymphoma (SMZL) is an indolent non-Hodgkin’s B-cell lymphoma. It presents morphologically by mature lymphoid B-cells. They conform to these immunological characteristics of marginal zone lymphocytes from secondary follicles. The tumor B-cells of SMZL do not have specific markers of immunophenotype and requires the exclusion of other non-Hodgkin’s B-cell lymphomas. There is an annual increase in the incidence of SMZL. There are refractory forms and progressive course of the SMZL. There is a huge variety of the mechanisms of evading tumor cells from immunological control. Unlike solid tumors, B-lymphoproliferative diseases are characterized by the expression of HLA I/II and co-stimulatory molecules (CD80 and CD86). Therefore, tumor B-lymphocytes can act as antigen-presenting cells (APC) for T lymphocytes. The T-cell immune response is known to play an important role in antitumor control. It is known that effective activation of T-lymphocytes requires the formation of an immunological synapse and the presence of two activation signals (antigen recognition and co-stimulation of CD28-CD80/86). According to the modern concept of tumor development, there is a gradual selection of tumor clones. As a result, only tumor cells that are invisible to the immune system remain. Mechanisms of evasion of tumor B-cells of SMZL from immune surveillance are currently not fully understood and are being actively studied.Objective: to study the expression features of antigens involved in the formation of immunological synapse in patients with SMZL in peripheral blood.Materials and methods. The study includes 10 primary SMZL patients; all patients have stage IV according to the Ann Arbor classification. Splenectomy was performed for all patients as a first stage of treatment. Two patients had progression of SMZL after splenectomy, which required chemotherapy. The control group included 25 healthy donors. Peripheral blood was used as a material for analysis. The study was conducted on a 6-color BD FACS Canto II flow cytometer (BD Biosciences, USA) immediately after diagnosis.Results. Tumor B-cells of SMZL are different from B-cells of healthy donors with a greater proportion of CD80+, FAS+, PD-1+-cells, which may correspond to activated B-cells. The proportion of CD4+PD-1+ and CD8+PD-1+ T-cells in patients with SMZL was higher in comparison with the control group. There was a large proportion of T-cells expressing PD-1 in the group of patients with SMZL progression after splenectomy in comparison with the group of patients with indolent course of SMZL. Conclusion. Thereby, tumor B-cells of the SMZL retains the features of non-tumor analogues. The most significant mechanism for evading immune surveillance in an SMZL is inhibition of the T-cell immunity via the PD-1–PD-L1 pathway. The most pronounced inhibition of T-cell immunity causes an uncontrolled tumor process.

The paper focuses on Epstein-Barr virus (EBV)-associated inflammatory pseudotumor in the spleen, an extremely rare disease which so far remained undefined in the Russian literature. The morphology of it is not characterized by any specific features and is represented by a spindle-cell component with pronounced inflammatory infiltration which complicates differential diagnosis. Previously this nosology was regarded within a group of the so-called inflammatory pseudotumors due to the similarity of the clinical course and radiological presentation with tumor processes. Today the term “inflammatory pseudotumor” is considered obsolete, since as pathogenesis was being studied within this disease group, the individual forms with similar morphology and different histogenesis were identified. Differential diagnosis in the context of additional diagnostic techniques is based in such cases on a wide range of reactive states, benign and malignant tumors.

The paper describes a case of autoimmune hemolytic anemia (AIHA) in a 27-year-old woman whose examination revealed mesenteric teratoma. AIHA was characterized by a hypertensive crisis and a temporary response to corticosteroid therapy that was complicated by the development of somatogenic psychosis and discontinued. A relapse of hemolysis developed 6 months later. The patient underwent laparoscopic splenectomy and removal of mesenteric root teratoma. Immediately after surgery, a hematological response was obtained as relief of hemolysis and restoration of a normal hemoglobin level. There is a sustained remission of AIHA for the next 16 months.