High incidence of thromboembolism in patients with chronic GVHD: association with severity of GVHD and donor-recipient ABO blood group

Dysregulated haemostasis in thrombo-inflammatory disease

Inflammatory disease is often associated with an increased incidence of venous thromboembolism in affected patients, although in most instances, the mechanistic basis for this increased thrombogenicity remains poorly understood. Acute infection, as exemplified by sepsis, malaria and most recently, COVID-19, drives 'immunothrombosis', where the immune defence response to capture and neutralise invading pathogens causes concurrent activation of deleterious prothrombotic cellular and biological responses. Moreover, dysregulated innate and adaptive immune responses in patients with chronic inflammatory conditions, such as inflammatory bowel disease, allergies, and neurodegenerative disorders, are now recognised to occur in parallel with activation of coagulation. In this review, we describe the detailed cellular and biochemical mechanisms that cause inflammation-driven haemostatic dysregulation, including aberrant contact pathway activation, increased tissue factor activity and release, innate immune cell activation and programmed cell death, and T cell-mediated changes in thrombus resolution. In addition, we consider how lifestyle changes increasingly associated with modern life, such as circadian rhythm disruption, chronic stress and old age, are increasingly implicated in unbalancing haemostasis. Finally, we describe the emergence of potential therapies with broad-ranging immunothrombotic functions, and how drug development in this area is challenged by our nascent understanding of the key molecular and cellular parameters that control the shared nodes of proinflammatory and procoagulant pathways. Despite the increasing recognition and understanding of the prothrombotic nature of inflammatory disease, significant challenges remain in effectively managing affected patients, and new therapeutic approaches to curtail the key pathogenic steps in immune response-driven thrombosis are urgently required.

Towards a Better Understanding of the Atypical Features of Chronic Graft-Versus-Host Disease: A Report from the 2020 National Institutes of Health Consensus Project Task Force

Alloreactive and autoimmune responses after allogeneic hematopoietic cell transplantation can occur in non-classical chronic graft-versus-host disease (chronic GVHD) tissues and organ systems or manifest in atypical ways in classical organs commonly affected by chronic GVHD. The National Institutes of Health (NIH) consensus projects were developed to improve understanding and classification of the clinical features and diagnostic criteria for chronic GVHD. While still speculative whether atypical manifestations are entirely due to chronic GVHD, these manifestations remain poorly captured by the current NIH consensus project criteria. Examples include chronic GVHD impacting the hematopoietic system as immune mediated cytopenias, endothelial dysfunction, or as atypical features in the musculoskeletal system, central and peripheral nervous system, kidneys, and serous membranes. These purported chronic GVHD features may contribute significantly to patient morbidity and mortality. Most of the atypical chronic GVHD features have received little study, particularly within multi-institutional and prospective studies, limiting our understanding of their frequency, pathogenesis, and relation to chronic GVHD. This NIH consensus project task force report provides an update on what is known and not known about the atypical manifestations of chronic GVHD, while outlining a research framework for future studies to be undertaken within the next three to seven years. We also provide provisional diagnostic criteria for each atypical manifestation, along with practical investigation strategies for clinicians managing patients with atypical chronic GVHD features.

Sex-Specific Cardiovascular Risks of Cancer and Its Therapies

In both cardiovascular disease and cancer, there are established sex-based differences in prevalence and outcomes. Males and females may also differ in terms of risk of cardiotoxicity following cancer therapy, including heart failure, cardiomyopathy, atherosclerosis, thromboembolism, arrhythmias, and myocarditis. Here, we describe sex-based differences in the epidemiology and pathophysiology of cardiotoxicity associated with anthracyclines, hematopoietic stem cell transplant (HCT), hormone therapy and immune therapy. Relative to males, the risk of anthracycline-induced cardiotoxicity is higher in prepubertal females, lower in premenopausal females, and similar in postmenopausal females. For autologous hematopoietic cell transplant, several studies suggest an increased risk of late heart failure in female lymphoma patients, but sex-based differences have not been shown for allogeneic hematopoietic cell transplant. Hormone therapies including GnRH (gonadotropin-releasing hormone) modulators, androgen receptor antagonists, selective estrogen receptor modulators, and aromatase inhibitors are associated with cardiotoxicity, including arrhythmia and venous thromboembolism. However, sex-based differences have not yet been elucidated. Evaluation of sex differences in cardiotoxicity related to immune therapy is limited, in part, due to low participation of females in relevant clinical trials. However, some studies suggest that females are at increased risk of immune checkpoint inhibitor myocarditis, although this has not been consistently demonstrated. For each of the aforementioned cancer therapies, we consider sex-based differences according to cardiotoxicity management. We identify knowledge gaps to guide future mechanistic and prospective clinical studies. Furthering our understanding of sex-based differences in cancer therapy cardiotoxicity can advance the development of targeted preventive and therapeutic cardioprotective strategies.

Efficacy and Safety of Ruxolitinib in Steroid-Refractory/Dependent Chronic Graft-versus-Host Disease: Real-World Data and Challenges

Steroid-refractory (SR) chronic graft-versus-host disease (cGVHD) is a major obstacle in recipients of allogeneic stem cell transplantation (HCT). Ruxolitinib is the first agent to demonstrate superior efficacy to the best available therapy, but real-life data are still lacking. Here we describe the results of ruxolitinib compassionate use for the treatment of SR/steroid-dependent cGVHD in a tertiary care university hospital. In this retrospective single-center study, we evaluated the outcomes of 48 patients diagnosed with SR-cGVHD who were treated with ruxolitinib. Forty-seven (98%) had moderate-severe disease, and 27 (56%) had received ≥2 lines of prior therapy (excluding steroids). Results were analyzed using SPSS version 26.0.01 and R version 3.4.3. The overall response rate was 77% (37 of 48), with 15% (7 of 37) in complete remission. The median time to response was 2 months (range, 0.5 to 8 months). Steroid tapering was achieved in 26 patients (54%) and definitive discontinuation was achieved in 10 patients (21%) after a median of 20 months (range, 1.5 to 60 months). Toxicity was predominantly hematologic, including a 33% rate of anemia and a 17% rate of thrombocytopenia. Overall survival at 2 years was significantly higher in responders compared with nonresponders (88% [95% confidence interval (CI), 65% to 96%] versus 49% [95% CI, 12% to 78%]; P = .01). At last follow-up, tapering of ruxolitinib had been started in 8 of 37 responders (22%). Our experience supports the efficacy of ruxolitinib in the treatment of SR-cGVHD, along with its steroid-sparing effect and manageable toxicity. Gradual tapering of ruxolitinib seems feasible without cases of GVHD flare. More studies and longer follow-up are needed to confirm these data, as well as to identify the ideal dose adjustments in cases of toxicity.