Over its 195-year history, classical Hodgkin lymphoma (cHL) has evolved from a potentially fatal disease into a highly curable one. This progress has become possible not only through an in-depth investigation of the morphological, immunohistochemical, and molecular-biological features of the tumor, but also through the development of highly sensitive and specific methods for assessing the extent of disease (PET-CT). The identification of prognostic factors and accurate staging has provided the basis for a risk-adapted strategy of chemo-radiotherapy in cHL Further refinement of therapeutic approaches in cHL relies on the timing of antitumor response: early achievement of a complete response allows treatment de-escalation, which is particularly important — given the unfavorable late effects — in pediatric patients.
Nevertheless, even in the era of precision diagnostics and molecularly targeted therapy, careful clinical assessment of cHL remains essential. Insufficient attention to rare tumor locations leads to a prolonged diagnostic work-up, disease dissemination, and irreversible consequences (for example, in cases of long-standing spinal cord compression by tumor masses).

Background. Chronic lymphocytic leukemia (CLL) is often accompanied by autoimmune complications, including antiphospholipid syndrome (APS). The presence of antiphospholipid antibodies contributes to a diagnostic paradox: laboratory tests show hypocoagulation and a high risk of bleeding, while actual hemostasis has a prothrombotic profile.
Objective. To demonstrate the stages of differential diagnosis of coagulopathy in a patient with newly diagnosed high-risk chronic lymphocytic leukemia (CLL) using a clinical case example.
Case Presentation. A 43-year-old female patient with newly diagnosed CLL (stage C according to Binet, unmutated IGHV status) was found to have a critical prolongation of activated partial thromboplastin time (aPTT) and prothrombin time (PT/INR) on screening hemostasis testing, which was interpreted as pronounced hypocoagulation. Differential diagnosis ruled out consumptive coagulopathy, hepatic failure, and vitamin K antagonist exposure. Additional investigations revealed that the hypocoagulation changes identified in the coagulogram coexisted with hypercoagulation features based on integrative tests (thromboelastography, thrombodynamics). This finding suggested a laboratory artifact related to the presence of lupus anticoagulant (LA), wherein standard plasma tests do not reflect the true hemostatic potential. Subsequent testing confirmed the presence of LA. The patient was prescribed anticoagulant therapy with low-molecular-weight heparin and received cytotoxic therapy without any thrombohemorrhagic complications.
Conclusion. The presented case illustrates a diagnostic pitfall associated with the presence of LA in patients with CLL, where standard coagulation tests (aPTT, PT/INR) do not reflect the true hemostatic potential but merely create an appearance of hypocoagulation. An integrated approach utilizing global hemostasis assays and LA testing enables timely diagnosis of antiphospholipid syndrome (APS), avoids erroneous withholding of antitumor and anticoagulant therapy, and prevents thrombotic complications.

RELEVANCE. Alloimmunization to erythrocyte antigens remains a key challenge in transfusion medicine, increasing the risk of post-transfusion reactions and complicating blood matching. Alloimmunization to erythrocyte antigens, with a frequency varying from 0.5% to 60%, poses the highest risk in patients with chronic erythrocyte disorders, remains a key challenge in transfusion medicine, increasing the risk of post-transfusion reactions and complicating blood matching. In the Russian Federation, the regulation of alloimmunization issues is governed by Order of the Ministry of Health No. 1134n (2020) and Resolution No. 641 (2025), focusing on the ABO, Rh, and Kell systems. This minimizes immunization risks for Rh, but may contribute to its increase for other antigens (Kell, Kidd, Duffy). Inflammation and genetics influence the development of immunization, emphasizing the need to analyze dynamics in oncology-hematology patients.
OBJECTIVE. To conduct a comprehensive analysis of the dynamics of alloimmunization to erythrocyte antigens in oncology-hematology patients at the Federal State Budgetary Institution "Russian Research Institute of Hematology and Transfusiology" of the Federal Medical and Biological Agency of Russia from 2008–2025.
MATERIALS AND METHODS. Retrospective analysis of 117 cases of newly detected immunization at the Federal State Budgetary Institution "Russian Research Institute of Hematology and Transfusiology" of the Federal Medical and Biological Agency of Russia. Data included antibody screening (IgG, IgM) for Rh systems (anti-D, C, c, E, Cw) and others (Kell, MNS, Kidd, Duffy). Methods: indirect antiglobulin test, identification with erythrocyte panels, adsorption. Processing in Microsoft Excel: calculation of frequencies, trends. Approved by the local ethics committee.
RESULTS. Since 2019, overall stabilization of alloimmunization incidence has been observed at 17–21 cases per year after a 45% decrease (from 62 cases per year in 2008–2013 to 35 in 2013–2019). In the Rh system, a 45% reduction in immunization by 2019, stabilization at 1–2 cases/year (predominantly anti-E ~28%, anti-D ~29%). In non-Rh systems, an increase of ~55% (from 9 in 2013–2019 to 14 in 2022–2025), dominated by MNS (~42%), Kell (~29%); peak in 2024 (12 cases). Non-specific antibodies ~40–50% of total, decrease by 82% in 2023–2024. The proportion of non-Rh increased to 35% by 2024.
CONCLUSION. A reduction in alloimmunization in the Rh system has been confirmed due to the regulation of hemotransfusions as reflected in normative documents, but the increase in other systems requires expanded typing. A personalized approach and molecular genotyping are recommended to reduce risks.