The course of multiple myeloma (MM) is influenced by a variety of factors, including the specificity of the tumour microenvironment (TME). The aim of this review is to provide insight into the interplay of treatment modalities used in the current clinical practice and TME. Bortezomib-based triplets are the standard for MM first-line treatment. Bortezomib is a proteasome inhibitor (PI) which inhibits the nuclear factor kappa B (NF-κB) pathway. However, bortezomib is decreasing the expression of chemokine receptor CXCR4 as well, possibly leading to the escape of extramedullary disease. Immunomodulatory drugs (IMiDs), lenalidomide, and pomalidomide downregulate regulatory T cells (Tregs). Daratumumab, anti-cluster of differentiation 38 (anti-CD38) monoclonal antibody (MoAb), downregulates Tregs CD38+. Bisphosphonates inhibit osteoclasts and angiogenesis. Sustained suppression of bone resorption characterises the activity of MoAb denosumab. The plerixafor, used in the process of stem cell mobilisation and harvesting, block the interaction of chemokine receptors CXCR4-CXCL12, leading to disruption of MM cells’ interaction with the TME, and mobilisation into the circulation. The introduction of several T-cell-based immunotherapeutic modalities, such as chimeric-antigen-receptor-transduced T cells (CAR T cells) and bispecific antibodies, represents a new perspective in MM treatment affecting TME immune evasion. The optimal treatment approach to MM patients should be adjusted to all aspects of the individual profile including the TME niche.

Disease- and treatment-mediated immunodeficiency might render SARS-CoV-2 vaccines less effective in patients with hematologic diseases. We performed a prospective non-interventional study to evaluate humoral response after one and two doses of mRNA-1273, BNT162b2, or ChAdOx1 nCoV-19 vaccine in 118 patients with different malignant or non-malignant hematologic diseases from three Croatian treatment centers. An electrochemiluminescent assay was used to measure total anti-SARS-CoV-2 S-RBD antibody titers. After one vaccine dose, 20/66 (33%) achieved seropositivity with a median antibody titer of 6.1 U/mL. The response rate (58/90, 64.4%) and median antibody titer (>250 U/mL) were higher after two doses. Seropositivity varied with diagnosis (overall p < 0.001), with the lowest rates in lymphoma (34.6%) and chronic lymphocytic leukemia (52.5%). The overall response rate in chronic myeloproliferative neoplasms (CMPN) was 81.3% but reached 100% in chronic myeloid leukemia and other non-myelofibrosis CMPN. At univariable analysis, age > 67 years, non-Hodgkin’s lymphoma, active treatment, and anti-CD20 monoclonal antibody therapy increased the likelihood of no vaccine response, while hematopoietic stem cell recipients were more likely to respond. Age and anti-CD20 monoclonal antibody therapy remained associated with no response in a multivariable model. Patients with the hematologic disease have attenuated responses to SARS-CoV-2 vaccines, and significant variations in different disease subgroups warrant an individualized approach.

Patients with lymphoid malignancies are at increased risk of death or prolonged infection due to COVID-19. Data on the influence of different antineoplastic treatment modalities on outcomes are conflicting. Anti-CD20 monoclonal antibodies increase the risk of prolonged infection. It is unclear whether this risk is affected by the choice of the antibody (rituximab vs. obinutuzumab). To elucidate the role of antineoplastic therapy on COVID-19 outcomes, KroHem collected data on patients with lymphoid malignancies diagnosed with COVID-19 between October 2020 and April 2021. A total of 314 patients were identified, 75 untreated, 61 off treatment and 178 on treatment. The mortality rate in untreated and off-treatment patients was 15% and 16%; 9% and 10% had prolonged infection. In the on-treatment group, 3% were still prolonged positive at time of data collection, 62% recovered and 35% died; 42% had prolonged infection. Disease type, use of anti-CD20 monoclonal antibodies, prior autologous stem-cell transplantation (ASCT) and line of treatment did not significantly affect mortality. Mortality was higher in older patients (p = 0.0078) and those treated with purine analogues (p = 0.012). Prolonged COVID-19 was significantly more frequent in patients treated with anti-CD20 monoclonal antibodies (p = 0.012), especially obinutuzumab, and purine analogues (p = 0.012). Age, prior ASCT and treatment line did not significantly affect risk of prolonged infection. These data suggest that increased age and use of purine analogues are main risk factors for increased mortality of COVID-19 in patients with lymphoid malignancies. Obinutuzumab further increases the risk of prolonged disease, but not of death, in comparison to rituximab. Epidemiological considerations should be taken into account when choosing the appropriate antineoplastic therapy for patients with lymphoid malignancies.

Background and Objectives: Ixazomib, used in combination with lenalidomide and dexamethasone (IRd), has shown efficacy in clinical trials for relapsed/refractory multiple myeloma (RRMM). Materials and Methods: This study evaluates the real-world effectiveness and safety of IRd in Croatian RRMM patients. A retrospective analysis was conducted on 164 RRMM patients treated with ixazomib at nine Croatian haematology centres from November 2016 to February 2023. Data on patient demographics, treatment regimens, and outcomes were collected and analysed using Kaplan–Meier survival curves and Cox proportional hazards models in R. The median age at ixazomib initiation was 66 years (range 40–91). Results: The overall response rate (ORR) was 65.8%, with 42% of patients achieving a very good partial response (VGPR) or better. The median progression-free survival (PFS) was 15.4 months, while median overall survival (OS) was 28.2 months. Hematologic toxicities included anaemia (53%), neutropenia (50%), and thrombocytopenia (45%). Infective complications, primarily COVID-19 and pneumonia, were reported in 38% of patients. The safety profile was consistent with previous studies, indicating manageable adverse events. Ixazomib-based therapy is effective and well tolerated in a real-world Croatian RRMM population. Conclusions: The findings align with clinical trial results, demonstrating the applicability of ixazomib in routine clinical practice. Further studies are needed to optimise treatment sequencing and improve patient outcomes.

(1) Background: This study aimed to examine the difference in efficacy and toxicity of involved-field (IFRT) and involved-site radiotherapy (ISRT) fields in infradiaphragmal aggressive non-Hodgkin lymphoma patients. (2) Methods: In total, 140 patients with infradiaphragmal lymphoma treated between 2003 and 2020 were retrospectively evaluated. There were 69 patients (49%) treated with IFRT, and 71 (51%) patients treated with ISRT. The median dose in the IFRT group was 36 Gy, (range 4–50.4 Gy), and in the ISRT group, it was 30 Gy (range 4–48 Gy). (3) Results: The median follow-up in the IFRT group was 133 months (95% CI 109–158), and in the ISRT group, it was 48 months (95% CI 39–57). In the IFRT group, locoregional control was 67%, and in the ISRT group, 73%. The 2- and 5-year overall survival (OS) in the IFRT and ISRT groups were 79% and 69% vs. 80% and 70%, respectively (p = 0.711). The 2- and 5-year event-free survival (EFS) in the IFRT and ISRT groups were 73% and 68% vs. 77% and 70%, respectively (p = 0.575). Acute side effects occurred in 43 (31%) patients, which is more frequent in the IFRT group, 34 (39%) patients, than in the ISRT group, 9 (13%) patients, p > 0.01. Late toxicities occurred more often in the IFRT group of patients, (10/53) 19%, than in the ISRT group of patients, (2/37) 5%, (p = 0.026). (4) Conclusions: By reducing the radiotherapy volume and the doses in the treatment of infradiaphragmatic fields, treatment with significantly fewer acute and long-term side effects is possible. At the same time, efficiency and local disease control are not compromised.

Background/Objectives: Ibrutinib has revolutionized the treatment of chronic lymphocytic leukemia but has off-target side effects, most notably cardiac. In order to evaluate the efficacy and toxicity of ibrutinib treatment, risk factors for adverse outcomes and the influence of pretreatment cardiologic evaluation, KroHem collected data on Croatian patients with chronic lymphocytic leukemia treated with this drug. Methods: This is a retrospective survey performed in order to analyze the efficacy and toxicity of ibrutinib in a real-life setting. Patients starting therapy with ibrutinib for chronic lymphocytic leukemia between the time the drug became reimbursable in 2015 and 31 December 2021 were included, irrespective of treatment line. Results: We identified 436 patients fulfilling entry criteria; 404 (92.7%) responded to treatment. Cardiovascular side effects occurred in 25.0% of patients and hemorrhagic in 15.6%. The dose of ibrutinib was permanently reduced in 22.2% of patients. Median follow-up of the cohort was 29 months (IQR 18–41 months), estimated median overall survival 75 months (IQR 36 months–not reached), progression-free survival 54 months (IQR 24–81 months) and time on ibrutinib treatment 44 months (IQR 14–78 months). Factors significantly related to overall survival in multivariate analysis were stage, treatment line and age. Factors significantly related to progression-free survival in multivariate analysis were treatment line, age and pretreatment history or ECG finding of cardiac arrhythmia. Factors significantly related to time on ibrutinib treatment in multivariate analysis were age, pretreatment history or ECG finding of cardiac arrhythmia, and permanent dose reduction for toxicity. Sex, FISH and the presence of arterial hypertension were not independently significantly related to any of these outcomes. Pretreatment cardiologic consultation did not improve time on ibrutinib therapy, progression-free survival, overall survival, risk of stopping treatment due to cardiovascular side effects or risk of cardiovascular or sudden death, neither in the whole cohort nor in the subgroup of patients with and without pretreatment cardiac arrhythmia. Conclusions: Our analysis confirms the efficacy and tolerability of ibrutinib for the treatment of chronic lymphocytic leukemia. Patients older than 75 do significantly less well. Routine pretreatment cardiologic consultation does not improve outcomes and should not be considered part of standard pretreatment assessment without additional proof of its usefulness. Future investigations should aim at identifying predictive factors, mechanisms, and preventive strategies for reducing cardiotoxicity in chronic lymphocytic leukemia patients taking Bruton tyrosine kinase inhibitors.