Diagnosis and Treatment of VOD/SOS After Allogeneic Hematopoietic Stem Cell Transplantation

Continuous Kidney Replacement Therapy in Children With Sinusoidal Obstruction Syndrome After Hematopoietic Cell Transplant: Outcome and Liberation

BACKGROUND

Sinusoidal obstruction syndrome (SOS), a serious complication after hematopoietic cell transplant (HCT), is associated with multiorgan dysfunction (MOD) and a high mortality rate. In severe cases, continuous kidney replacement therapy (CKRT) is initiated to manage fluid overload (FO) and acute kidney injury. Studies that evaluate the use of CKRT in this population are lacking. The aim of our study was to assess the outcome of critically ill children with severe SOS post HCT who received CKRT. We also sought to assess factors associated with survival and liberation post CKRT.

PROCEDURE

Retrospective review of all children admitted to the intensive care unit (ICU) with SOS post HCT who received CKRT from January 2010 to August 2022.

RESULTS

Among the 53 children who received CKRT post HCT, 13 had severe SOS. The median age was 6 years; 62% were males, and most (77%) received allogeneic HCT. In this cohort, 92% required respiratory support and 85% required vasopressor support. The ICU survival rate was 62%. Survivors experienced lower cumulative FO on the 2 days following CKRT initiation (-4.2% in survivors vs. -0.5% in non-survivors, p = 0.07). Higher urine output on D1 and D2 after discontinuation of CKRT was associated with successful liberation.

CONCLUSIONS

In this study of post-HCT children with SOS and MOD who received CKRT, 62% survived until ICU discharge. This survival rate is encouraging as it approximates the survival rates of general pediatric cohorts treated with CKRT. Reducing FO after initiation of CKRT can improve survival in these children.

A Second Look: Retrospective Identification of Thrombotic Microangiopathy in Pediatric Stem Cell Transplant Patients With Veno-Occlusive Disease

BACKGROUND

Veno-occlusive disease (VOD) and transplant-associated thrombotic microangiopathy (TA-TMA) remain a diagnostic and therapeutic challenge for patients undergoing hematopoietic stem cell transplant (HSCT). Both VOD and TA-TMA share an underlying etiology of microvascular endothelial damage. Potential under-recognition of TA-TMA in the context of VOD leaves HSCT recipients vulnerable to additional endothelial damage, and risk of end-organ failure.

METHODS

A cohort of 44 pediatric HSCT recipients diagnosed with VOD between 2010and 2019 were retrospectively evaluated for the development of TA-TMA within 1 week before and 2 months after VOD diagnosis. Patients were classified into three categories: sole diagnosis of VOD (VOD), concurrent clinical diagnosis of TA-TMA during the VOD course (VOD+TA-TMA), and patients with VOD who on retrospective review satisfied criteria for diagnosis of TA-TMA (VOD+rTA-TMA).

RESULTS

A total of 42 patients were evaluated and 50% of the patients were diagnosed clinically with TA-TMA (5) or where retrospectively identified to have TA-TMA (16). There was no difference in the severity of the course of VOD between the three groups based on need for intubation, dialysis, and pediatric intensive care unit (PICU) care. Patients in the VOD only group had the highest survival at 1 year (66.7%, n = 14) compared with patients in the VOD+TA-TMA group (60%, n = 3) and VOD+rTA-TMA group (62.5%, n = 10), p = 0.9582.

CONCLUSION

Better understanding of the association between these two endotheliopathies is essential to improve diagnosis, treatment, and prevention of potentially fatal adverse outcomes in transplant recipients.

Utility of ursodiol prophylaxis against sinusoidal obstruction syndrome (SOS)/ veno-occlusive disease (VOD) in acute leukemia patients receiving gemtuzumab-ozogamicin (GO) or inotuzumab-ozogamicin (InO)

PURPOSE

Sinusoidal obstructive syndrome (SOS)/veno-occlusive disease (VOD) is a serious complication in hematopoietic stem-cell transplant (HSCT) patients. Gemtuzumab-ozogamicin (GO) and InO are known to cause SOS/VOD in leukemic and transplant populations. Due to limited data on ursodiol prophylaxis in non-HSCT patients, we aimed to assess hepatotoxicity, SOS/VOD incidences, time to hepatotoxicity, and confirmed SOS/VOD in adults receiving GO or InO ± ursodiol.

METHODS

A multicenter, retrospective chart review of adult acute leukemia patients who received ≥1 dose of GO or InO at DFCI/some of the Harvard Cancer Centers during 4-year period (9/1/2017-9/1/2021). Acute promyelocytic leukemia patients and post-GO or InO HSCT-recipients (100-day follow-up period) were excluded. Descriptive summaries are provided, direct comparisons were made using Student T-test (continuous variables) and Fisher's exact test (categorical variables).

RESULTS

In our population (N = 82), 87.8% received ursodiol and 12.2% did not. There were no significant differences in baseline to peak hepatic labs. The No-Ursodiol Group had higher incidence of Grade 3 aspartate aminotransferase (AST) transaminitis vs. the Ursodiol Group (60% vs. 20.8%; p = 0.015), and a trend towards shorter mean time to Grade 3 AST transaminitis (18.5 vs. 23.8 days; p = 0.30). Moreover, 4.2% of Ursodiol Group developed SOS/VOD vs. 0% in the No-Ursodiol Group (NS). Three patients developed SOS/VOD: 2 received GO, 1 received InO, and 2 were alive by the end of the follow-up period.

CONCLUSION

In our cohort, ursodiol prophylaxis in adults receiving GO/InO is not associated with lower incidences of hepatotoxicity, SOS/VOD, or time to Grade 3 AST transaminitis, but is associated with decreased incidence of AST elevations.

A case of late-onset sinusoidal obstruction syndrome diagnosed histologically before meeting diagnostic criteria

Sinusoidal obstruction syndrome (SOS), also known as hepatic veno-occlusive disease (VOD), is a life-threatening complication of hematopoietic stem cell transplantation. In severe cases, SOS/VOD progresses to multiple organ failure with a mortality rate higher than 80%. Early diagnosis and treatment based on severity assessment improve the prognosis of severe SOS/VOD, but conventional diagnostic criteria may be insufficient for an early diagnosis. We herein report a case of severe late-onset SOS/VOD that was histologically proven before clinical findings become evident. Although defibrotide therapy was started before the clinical diagnostic criteria were met, the disease progressed to multiple organ failure. This case suggests that some patients require earlier treatment before the appearance of clinical findings such as ascites and weight gain or hyperbilirubinemia, and supports the need to establish methods for predicting the onset and severity of SOS/VOD.

An international survey to better understand the current incidence, severity, and management of VOD/SOS

This international questionnaire survey aimed to explore the current incidence, diagnostic policies, management, and outcomes of veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) among healthcare providers involved in the management of these patients. A questionnaire was e-mailed to practitioners with an interest in allogeneic hematopoietic cell transplantation (allo-HCT). Of the respondents, 144 of 215 (67.0%) felt that early detection or diagnosis of VOD/SOS was difficult. Regarding diagnostic criteria, 142 (66.1%) already declared using the 2023 EBMT refined criteria. Most respondents (163/215, 75.8%) found these recent refined EBMT criteria useful for diagnosis, and 193 (89.8%) found the severity criteria easy to use. The major risk factors identified for VOD/SOS were a second allo-HCT (41.4%), pre-existing liver disease (54.9%), and prior use of antibody-drug conjugates (49.8%). Preferences for starting VOD/SOS treatment varied, with 61 (28.4%) preferring initiating therapy at a mild stage, and 122 (56.7%) preferring the moderate stage. In summary, this survey provided valuable insight into the challenges and opportunities of the identification and management of VOD/SOS. By improving current knowledge and increasing collaboration among healthcare professionals, early detection, management, and clinical outcomes for patients with this potentially serious complication can also be improved.

Hepatic Sinusoidal Obstruction Syndrome (SOS) Associated with Checkpoint Inhibitor Therapy

Sinusoidal obstruction syndrome (SOS) is a distinctive and potentially fatal form of hepatic injury that mainly occurs after hematopoietic-stem cell transplantation but also due to many other conditions including drug or toxin exposure. Recently, immune checkpoint inhibitors (ICIs) have revolutionised the treatment of many solid organ malignancies. Furthermore, as their use has become more widespread, rare toxicities have emerged. The difficulty lies in diagnosing these unusual toxicities with an incidence of as low as less than 1% hence defined as SOS. The development of the disease can be rapid and unpredictable. The severe forms of SOS may result in multi-organ dysfunction with a high mortality rate (>80%). We present the case of a patient with metastatic lung adenocarcinoma treated with the ICI pembrolizumab who developed SOS with marked portal hypertension as a rare severe, toxic side effect of immunotherapy. This report highlights the importance of considering SOS in patients who develop liver dysfunction and/or portal hypertension during or after immunotherapy for neoplastic disease. Early identification and severity assessment is crucial in facilitating prompt diagnosis and timely treatment, improving the prognosis of our patients.

LEARNING POINTS

Understand less common side effects of immunotherapy, now used in daily clinical practice.Consider sinusoidal obstruction syndrome (SOS) in patients who develop liver dysfunction and/or portal hypertension during or after immunotherapy for neoplastic disease.Early identification and severity assessment is crucial in facilitating prompt diagnosis and timely treatment, improving the prognosis of patients.

Transjugular Liver Biopsy: The Key to a Rare Etiology of Cholestatic Hepatitis after Bone Marrow Transplantation

Introduction

Hematopoietic stem cell transplantation (HSCT) is associated with multiple complications, such as sinusoidal obstruction syndrome (SOS) (hepatomegaly, ascites, jaundice, and thrombocytopenia) and graft-versus-host disease (GVHD) (with the skin, gastrointestinal tract, and liver being the main targets). These entities may present overlapping clinical findings, being considered differential diagnoses, but their coexistence is rare.

Case Presentation

A 29-year-old male with acute myeloid leukemia underwent HSCT. On day (D)+20, he developed hyperbilirubinemia, pleural effusion, ascites, and painful hepatomegaly. Abdominal ultrasound was suggestive of SOS, and defibrotide was initiated. On D+44, acute cutaneous, intestinal, and hepatic GVHD developed which improved after treatment with methylprednisolone. On D+132, there was worsening cholestasis and abdominal pain. MRCP revealed strictures in several segments of the intrahepatic bile ducts and irregularity of the main bile duct. Due to aggravation of liver enzyme changes and clinical worsening, he was admitted to the Intensive Care Unit. Due to persistence of severe hyperbilirubinemia (30 mg/dL) and thrombocytopenia (30,000 cell/uL), he underwent a hepatic hemodynamic study which revealed a hepatic venous pressure gradient of 10 mm Hg. The transjugular liver biopsy revealed canalicular hepatic cholestasis, bile duct injury, and focal hepatocellular necrosis suggestive of GVHD as well as injury to centrilobular veins and centrilobular necrosis compatible with possible SOS. Mycophenolate mofetil was started, but on D+195, the patient died of septic shock.

Discussion/Conclusion

This case is notable for its complexity and for demonstrating the rare coexistence of histological features of SOS and GVHD. Although the clinical and laboratory findings may be sufficient for the diagnosis, it is important to highlight the importance of liver hemodynamic study and transjugular liver biopsy in these patients who often have severe thrombocytopenia, for the characterization and histological confirmation of cholestatic hepatitis, especially when the etiology may be multifactorial.

Hepatic Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease (SOS/VOD) Primary Prophylaxis in Patients Undergoing Hematopoietic Stem Cell Transplantation: A Network Meta-Analysis of Randomized Controlled Trials

Introduction: Hepatic sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a major complication following hematopoietic stem cell transplantation, resulting from immune and chemical toxicity in the sinusoidal endothelium and hepatocellular damage. In the most severe cases, multiorgan dysfunction occurs, so it is essential to promptly identify patients at greater risk of SOS/VOD and to adopt prophylactic strategies. Objectives: This study aims to systematize the impact of different approaches as primary prophylaxes against SOS/VOD in patients undergoing hematopoietic stem cell transplantation (HSCT). Methods: A systematic review and meta-analysis of randomized clinical trials evaluating different strategies for primary prophylaxis of SOS/VOD was carried out in pairwise fashion and with a consistent network structure. The odds ratio (OR) and corresponding confidence intervals were calculated using the random-effects model. Heterogeneity was assessed by the I2 method and the efficacy of each approach was estimated by SUCRA (surface under the cumulative ranking curve). Results: Considering all patients undergoing HSCT, ursodeoxycholic acid (UDCA) [OR = 0.38, 95%CI 0.14-1.06, SUCRA = 0.720] was associated with a lower incidence of VOD while defibrotide reached a modest reduction in its incidence [OR = 0.64, 95%CI 0.23-1.67; SUCRA = 0.486]. Considering the subgroup of patients undergoing hematopoietic progenitors allotransplantation, defibrotide scored higher [OR = 0.51, 95%CI 0.09-2.85, SUCRA = 0.650] by comparison with UDCA [OR = 0.53, 95%CI 0.14-1.96, SUCRA = 0.639]. Conclusions: This is the first meta-analysis comparing primary prophylaxes against SOS/VOD. UDCA yielded more promising results when considering all patients undergoing hematopoietic stem cell transplantation, yet, in a subgroup analysis of the ones exposed to allogeneic grafts, it becomes not significantly overrun by defibrotide.

The benefits of prophylactic defibrotide: Are the tides turning?

BACKGROUND

Veno-occlusive disease (VOD) is a life-threatening endotheliopathy that can occur after stem cell transplant (SCT). Numerous risk factors contribute to the development of VOD during SCT, and the role of prophylactic defibrotide (DF) in mitigating these risks remains unclear.

OBJECTIVE

We compare not only the incidence of VOD development, but also the severity of VOD and survival outcomes between patients who did and did not develop VOD and did or did not receive prophylactic DF.

STUDY DESIGN

In this single-center retrospective study of 58 pediatric SCT patients from 2008 to 2022, we compare the demographics, risk profiles, and outcomes within three cohorts: Group 1: prophylactic DF and no VOD (n = 5), Group 2: prophylactic DF and development of VOD (n = 6), and Group 3: treatment DF for patients who developed VOD (n = 47).

RESULTS

Patients with VOD who did not receive prophylactic DF had higher severity classification of disease at onset (very severe 80.9% vs. 66.7%, p = .592) and at maximum severity (very severe 89.4% vs. 83.3%, p = .532), as opposed to mild, moderate, or severe categorization compared to those who did not receive prophylactic DF. Patients who developed VOD and did not receive prophylactic DF had a lower 1-year survival probability compared to those who received prophylactic DF and still developed VOD (51.1% vs. 75% alive at 1 year, excluding the two subjects without adequate follow-up time, p = .266).

CONCLUSION

Although, not statistically significant in our small retrospective study, there is potential overall survival and decreased VOD severity benefits of prophylactic DF.

Burden of illness of non-hematopoietic stem cell transplant-related hepatic sinusoidal obstruction syndrome: A systematic review

Background

Sinusoidal obstruction syndrome (SOS)/veno-occlusive disease (VOD) is generally associated with hematopoietic cell transplant (HCT), but little is known about this condition outside the HCT setting. This systematic review examines the burden of illness and current management approaches in non-HCT SOS/VOD.

Methods

We searched Embase, Medline, and grey literature sources for non-HCT SOS/VOD studies published 2002-2023. Inclusion criteria were studies of any design reporting incidence, diagnosis, underlying disease and any ongoing treatment at the time of SOS/VOD onset, management of non-HCT SOS/VOD, clinical burden, health-related quality of life, healthcare resource use, costs, and patients' unmet needs. Studies investigating pulmonary VOD or SOS/VOD related to the ingestion of pyrrolizidine alkaloids were excluded.Two authors independently screened results, extracted data, and assessed the methodological quality of studies using the Motheral scale for retrospective studies, Newcastle-Ottawa scale for prospective studies and case control studies, the Cochrane risk of bias tool for randomized controlled trials, and the Joanna Briggs Institute critical appraisal tool for case series. Results were synthesized narratively.

Results

Ninety-two studies were included; 57 % were retrospective cohort studies and 70 % were conducted in the US or Europe. The study populations included hematological and solid tumor cancers, various indications for liver transplant, Wilms' tumor, and transfusion-dependent beta thalassemia. Non-HCT SOS/VOD occurs most frequently in people with colorectal liver metastases (CRLM), acute lymphoblastic leukemia (ALL), and acute myeloid leukemia (AML). Approximately 35 % of oxaliplatin-treated CRLM patients and 5 % of ALL and AML patients have non-HCT SOS/VOD. Diagnosis varies according to initial disease setting. Defibrotide is the most frequently reported treatment. Most studies did not clearly report their data sources or methods of outcome assessment.

Conclusion

Non-HCT SOS/VOD occurs in diverse disease conditions, therefore guidelines on diagnosis and treatment are needed to optimize management in clinical practice.

Fluid Overload in Children Following Hematopoietic Cell Transplant: A Comprehensive Review

Fluid overload significantly increases morbidity and mortality in critically ill children. Following hematopoietic cell transplant (HCT), children are at a high risk of fluid accumulation due to essential increased fluid intake for nutrition, blood products, and antimicrobials. In addition, many complications predispose these children to capillary leak and fluid overload (FO), such as sinusoidal obstruction syndrome, engraftment syndrome, sepsis, and acute kidney injury (AKI). FO > 10% occurs in nearly half of children following HCT and is associated with a lower PICU survival rate. In addition, in children with acute respiratory failure post HCT, each 1% increase in cumulative fluid balance on d 3 increases the odds of PICU mortality by 3%. Furthermore, FO worsens AKI. Tools such as the renal angina index and urinary biomarkers such as neutrophil gelatinase-associated lipocalin can help identify patients at risk of AKI and FO. Early detection, prevention, and intervention are crucial to improving outcomes in this population. Management strategies include fluid restriction, diuretics, and continuous kidney replacement therapy (CKRT) when FO exceeds 10% and other measures have failed.

Case report: Nephrotic syndrome and portal hypertensive ascites after allogeneic hematopoietic stem cell transplantation: a rare manifestation of chronic graft-versus-host disease

Chronic graft-versus-host disease (GVHD) is a major complication after allogeneic hematopoietic stem cell transplantation (HSCT). Chronic GVHD may have atypical manifestations affecting non-classical organs. The diagnosis in patients with atypical manifestations of chronic GVHD is particullarly challenging, and there is a lack of knowledge regarding their pathogenesis and treatment. We reported a case who developed post-HSCT nephrotic syndrome and portal hypertensive ascites, which are both rare and atypical manifestations of chronic GVHD. Kidney biopsy revealed membranous nephropathy and renal thrombotic microangiopathy with glomerular immune deposits, suggesting antibody-mediated kidney injury. Treatment with ruxolitinib resulted in remission of both nephrotic syndrome and ascites, suggesting a role of cytokines in the pathogenesis. This case highlighted the awareness of nephrotic syndrome and portal hypertensive ascites as atypical manifestations of chronic GVHD, and the efficacy of ruxolitinib for the two manifestations.

Verification of the Prediction Accuracy of a Biomarker-Based Prognostic for Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome (VOD/SOS) After Hematopoietic Cell Transplantation (HCT)

Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is a potentially life-threatening complication of hematopoietic cell transplantation (HCT), especially in severe cases. Patient outcomes are improved with prompt treatment; however, diagnosing this disease is challenging as many clinical symptoms of VOD/SOS overlap with other post-HCT complications. A biomarker-based prognostic test for the assessment of VOD/SOS risk, termed "VODCheck" was developed in a previous study but has not yet been validated. This study aimed to validate the accuracy of VODCheck as a prognostic test for VOD/SOS in an independent cohort of patients. VODCheck incorporates hyaluronan (HA), angiopoietin-2 (ANG-2), and thrombomodulin (TM) based on their association with VOD/SOS, their analytical characteristics, and their ability to complement each other in a multivariate prognostic model. To validate VODCheck we measured plasma biomarker levels from a subset of patients enrolled in the control arm of a phase 3 study that tested VOD/SOS prophylaxis. We used a hierarchical design with prespecified primary (day 7), secondary A (day 15), and secondary B (day 1) hypotheses to verify the prognostic accuracy of VODCheck post-HCT. The cases of VOD/SOS (n = 22) were age-matched ∼1:3 with controls (n = 65). VODCheck was prognostic of VOD/SOS risk at all 3 time points with an area under the curve (AUC) of .815 (P < .001) for day 7, .836 (P < .001) for day 15, and .706 (P = .002) for day 1 post-HCT. A multivariate analysis confirmed the prognostic accuracy of VODCheck after adjustment for confounders such as age, VOD/SOS risk status, primary disease, and ozogamicin treatment. VODCheck was validated as an independent predictor of risk for VOD/SOS within 15 days post-HCT and appears to provide clinicians with actionable information to improve patient care.

Novel method for assessing sinusoidal obstruction syndrome using four-dimensional computed tomography

Introduction

To diagnose sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), transabdominal ultrasonography is usually used to detect hemodynamic changes, but we tried to detect the changes using four-dimensional computed tomography (4D-CT). A 42-year-old Japanese woman was diagnosed with late-onset SOS/VOD with transabdominal ultrasonography and was also assessed using 4D-CT. Method We analyzed the portal vein (PV) contrast effect every 1.5 seconds and plotted the values of the contrast effect. With this graph, we analyzed three hemodynamic parameters.

Result

We found that these parameters correlated with the patient's status and indicated stasis due to sinusoid constriction.

Conclusion

4D-CT may become a helpful tool to diagnose and follow up with SOS/VOD.

Hepatic veno-occlusive disease with asparaginase products: a review of cases reported to the FDA adverse event reporting system and published in the literature

Multiple asparaginase products have been approved by the United States (US) Food and Drug Administration (FDA) for the treatment of acute lymphoblastic leukemia in pediatric and adult patients. Hepatic veno-occlusive disease (VOD) is a potentially life-threatening disorder resulting from damage to the liver sinusoidal endothelial cells. To evaluate this safety concern with asparaginase (i.e. Asparlas, Oncaspar, Rylaze, and Erwinaze) use, we performed a postmarketing review of hepatic VOD reports retrieved from the FDA Adverse Event Reporting System database and literature with these four products. We identified 55 cases of hepatic VOD following exposure to asparaginase products. The median time to onset of hepatic VOD from the first dose of asparaginase was 18 days (interquartile range 13-24 days). Notably, 80% (44/55) of cases reported grades 3-5 VOD per the Common Terminology Criteria for Adverse Events. Although patients received asparaginase with standard chemotherapeutic agents known to induce VOD, case-level data indicates that asparaginase products may have contributed to hepatic VOD. Asparaginase products are associated with hepatotoxicity and thrombosis, suggesting a plausible mechanism for asparaginase-induced hepatic VOD. Based on the totality of data, including temporality and biologic plausibility, we determined hepatic VOD to be a class effect with asparaginase products. These data contributed to the addition of hepatic VOD to the hepatoxicity warning in the US Prescribing Information for asparaginase class products.

Allogeneic Stem Cell Transplant in Hematological Disorders: A Decade of Experience

Background: Allogeneic hematopoietic cell transplantation (allo-HCT) is a complex procedure with the potential to provide curative treatment for various hematological disorders. This study aims to evaluate the outcomes of allo-HCT in hematological diseases and identify significant complications in a single-center setting. Materials and Methods: We conducted a retrospective analysis of 180 patients with hematological diseases who underwent allo-HCT between January 2011 and December 2021. Key outcomes, including indications for transplantation, overall survival, engraftment time, relapse rates, graft-versus-host disease (GVHD), and transplant-related mortality (TRM) were assessed. Results: The most common indications for allo-HCT were benign hematological diseases, particularly aplastic anemia, and thalassemia major. Despite the majority of patients receiving fully matched transplants, acute GVHD was observed in 30% of the cohort. Graft failure occurred in 13 patients, with primary and secondary graft failure rates of 1.6% and 5.5%, respectively. Sepsis emerged as the primary cause of non-relapsed mortality at day 100 and beyond. The overall survival rate in this study was 62%, with 79% of patients disease-free on their last visit. Conclusion: This study provides valuable insights into the treatment strategies and patient care of allo-HCT for hematological disorders by offering a comprehensive overview of multiple relevant outcomes. The findings underscore the significance of addressing complications and risk factors associated with allogeneic transplantation, including GVHD and infections. Future research should focus on further optimizing transplantation techniques to minimize complications and enhance patient survival.

Hepatic sinusoidal obstruction syndrome after immune-checkpoint-inhibitor therapy: when the liver sends SOS

A woman in her 50s presented to the hospital with new-onset jaundice and ascites. Her medical history included a melanoma of the right shoulder, diagnosed 8 months before, for which she had received four cycles of ipilimumab and nivolumab. Due to the oncological history and previous immunotherapy, an immune-checkpoint-inhibitor (ICI)-induced hepatitis was suspected, and a high-dose corticosteroid treatment was initiated. However, as there was no improvement in the liver function tests, a percutaneous liver biopsy was performed for further diagnostic clarification. Histological analysis ultimately identified a hepatic sinusoidal obstruction syndrome (SOS) as the underlying cause of liver dysfunction and portal hypertension. ICI-related hepatic SOS represents an extremely rare adverse event related to immunotherapy that should be considered in all patients with treatment-refractory ICI-related hepatotoxicity and clinical signs of portal hypertension.

Risk Factors for Sinusoidal Obstruction Syndrome After Hematopoietic Stem Cell Transplantation in Children and Young Adults: A Systematic Review and Meta-Analysis

OBJECTIVE AND BACKGROUND

Sinusoidal obstruction syndrome (SOS) is a life-threatening complication in hematopoietic stem cell transplantation (HSCT) patients. However, the related risk factors in pediatric and young adult HSCT recipients remain unclear. Thus, we conducted this meta-analysis to identify potential risk factors for SOS in children and young adults undergoing HSCT.

METHOD

We acquired related articles through searching PubMed, EMBASE, and the Cochrane Library up to May 31, 2024. We calculated odds ratios (ORs) and corresponding 95% confidence intervals (CIs) to identify potential risk factors.

RESULTS

A total of 12 studies with 7644 HSCT recipients were included. Bone marrow transplantation (OR = 1.35, 95% CI: 1.03-1.77, I2 = 0%), busulfan (BU) (OR = 3.63, 95% CI: 1.78-7.38, I2 = 70%), and fludarabine (FLU) (OR = 1.55, 95% CI: 1.09-2.21, I2 = 16%) were risk factors for SOS after HSCT in children and young adults.

CONCLUSION

Bone marrow transplantation and the use of BU or FLU might be risk factors for SOS after HSCT in children and young adults.

ANZTCT practice statement: sinusoidal obstruction syndrome/veno-occlusive disease diagnosis and management

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a life-threatening complication which can develop after haemopoietic stem cell transplantation (HSCT) and some antibody-drug conjugates. Several SOS/VOD diagnostic and management guidelines exist, with the most recent and refined being the European Society for Blood and Marrow Transplantation adult and paediatric guidelines. Timely diagnosis and effective management (including the availability of therapeutic options) significantly contribute to improved patient outcomes. In Australia and New Zealand, there is variability in clinical practice and access to SOS/VOD therapies. This review aims to summarise the current evidence for SOS/VOD diagnosis, prevention and treatment and to provide recommendations for SOS/VOD in the context of contemporary Australasian HSCT clinical practice.

Liver stiffness measurements predict Sinusoidal Obstructive Syndrome after hematopoietic stem cell transplantation

Sinusoidal Obstructive Syndrome (SOS) is a life-threatening complication after hematopoietic stem-cell transplantation (HSCT), characterized by post-sinusoidal portal hypertension. FibroScan is used to assess portal hypertension non-invasively. We assessed transient elastography (TE) applicability in diagnosing SOS. The study included 27 adult patients, 11 underwent TE for high SOS risk pre-HSCT, 17 underwent TE post-HSCT due to bilirubin ≥2 mg/dl with no definite diagnosis of SOS. The first group had median Liver Stiffness Measurement (LSM) of 7.4 kPa (range, 3.3-22.5). Based on LSM results, conditioning regimen was modified for six patients and two of them developed SOS. Only one patient who did not have protocol adjustment experienced SOS. No patient with LSM < 7 kPa developed SOS. The second group had median LSM of 7.7 kPa (4.4-31.5). Median LSM after HSCT was significantly higher in patients who subsequently developed established SOS (n = 10) compared to patients who did not (n = 8), with values of 10.7 kPa (5.6-31.5) and 5.9 kPa (4.4-13.8), respectively (p = 0.02). An LSM cut-off of 7.5 kPa had a sensitivity and specificity of 75 and 80% for diagnosing SOS. In conclusion, pre-HSCT LSM can help adjustment of conditioning regimen in patients with high-risk for SOS. Post-HSCT LSM can help in early diagnosis of SOS.

Hepatic Veno-Occlusive Disease and Colorectal Cancer: Expect the Unexpected

Sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) is a rare liver vascular condition, potentially life-threatening, with clinical signs of portal hypertension, frequently reported in relation to bone marrow transplantation and possibly in non-transplantation-related chemotherapy. We report the case of a 65-year-old female patient who insidiously developed fatigue, mild tenderness of the right upper abdominal quadrant, hepato-splenomegaly and slight weight gain consecutive to ascites development, as well as persistent elevation of transaminases and mild thrombocytopenia. To note, she had a previous history of colorectal cancer (CRC) with liver metastases and several courses of chemotherapy. Abdominal duplex and elastography measurements made the diagnosis of cirrhosis improbable. A lot of lab work-ups were performed in order to rule out several diseases and conditions. Further, transjugular access was used to perform the measurement of the hepatic venous pressure gradient and liver biopsy that confirmed SOS/VOD. In late 2023, she was diagnosed with endometrial adenocarcinoma, requiring chemotherapy again. At present, the liver condition is stationary, but the prognosis is, however, uncertain. In conclusion, we presented the atypical case of a female patient who developed portal hypertension syndrome associated with the late onset of SOS/VOD, after 5-fluorouracil and oxaliplatin chemotherapy for CRC and liver metastases, subsequently diagnosed with endometrial adenocarcinoma, which posed many diagnostic and therapeutic challenges. Given the potentially bad outcome, an early diagnosis of SOS/VOD in patients receiving drugs of risk is important not only to stratify further risk, but also to initiate an appropriate therapy in order to improve the prognosis.

Veno-Occlusive Disease: A Life-saving Novel Approach With Plasma Exchange, IVIG, and Steroid, Without Defibrotide

INTRODUCTION

Hepatic veno-occlusive disease (VOD) is a critical medical emergency with a high mortality rate of up to 90% if not promptly treated. Defibrotide is the only approved medication for VOD treatment, exhibiting anti-inflammatory, antithrombotic, and anti-ischemic properties. This report presents a case of severe VOD in a patient undergoing acute lymphoblastic leukemia (ALL) treatment.

CASE PRESENTATION

We describe the successful and rapid treatment of severe VOD in an ALL patient using therapeutic plasma exchange (TPE), intravenous immunoglobulin (IVIG), and methylprednisolone (MPZ). The patient showed significant clinical and laboratory improvement after this combined therapeutic approach.

CONCLUSION

This case highlights the effectiveness of TPE, IVIG, and MPZ in the treatment of severe VOD in ALL patients, providing insights into alternative therapeutic strategies in the absence of Defibrotide.

Diagnosing and Grading of Sinusoidal Obstructive Syndrome after Hematopoietic Stem Cell Transplant of Children, Adolescent and Young Adults treated in a Pediatric Institution with Pediatric Protocols

Sinusoidal obstructive syndrome (SOS), or veno-occlusive disease, of the liver has been recognized as a complex, life-threatening complication in the posthematopoietic stem cell transplant (HSCT) setting. The diagnostic criteria for SOS have evolved over the last several decades with a greater understanding of the underlying pathophysiology, with 2 recent diagnostic criteria introduced in 2018 (European Society of Bone Marrow Transplant [EBMT] criteria) and 2020 (Cairo criteria). We sought out to evaluate the performance characteristics in diagnosing and grading SOS in pediatric patients of the 4 different diagnostic criteria (Baltimore, Modified Seattle, EBMT, and Cairo) and severity grading systems (defined by the EBMT and Cairo criteria). Retrospective chart review of children, adolescent, and young adults who underwent conditioned autologous and allogeneic HSCT between 2017 and 2021 at a single pediatric institution. A total of 250 consecutive patients underwent at least 1 HSCT at UCSF Benioff Children's Hospital San Francisco for a total of 307 HSCT. The day 100 cumulative incidence of SOS was 12.1%, 21.1%, 28.4%, and 28.4% per the Baltimore, Modified Seattle, EBMT, and Cairo criteria, respectively (P < .001). We found that patients diagnosed with grade ≥4 SOS per the Cairo criteria were more likely to be admitted to the Pediatric Intensive Care Unit (92% versus 58%, P = .035) and intubated (85% versus 32%, P = .002) than those diagnosed with grade ≥4 per EBMT criteria. Age <3 years-old (HR 1.76, 95% [1.04 to 2.98], P = .036), an abnormal body mass index (HR 1.69, 95% [1.06 to 2.68], P = .027), and high-risk patients per our institutional guidelines (HR 1.68, 95% [1.02 to 2.76], P = .041) were significantly associated with SOS per the Cairo criteria. We demonstrate that age <3 years, abnormal body mass index, and other high-risk criteria associate strongly with subsequent SOS development. Patients with moderate to severe SOS based on Cairo severity grading system may correlate better with clinical course based on ICU admissions and intubations when compared to the EBMT severity grading system.

Shear wave elastography and dispersion imaging for hepatic veno-occlusive disease prediction after pediatric hematopoietic stem cell transplantation: a feasibility study

BACKGROUND

Non-invasive imaging modalities are warranted for diagnosing and monitoring veno-occlusive disease because early diagnosis and treatment improve the prognosis.

OBJECTIVE

To evaluate the usefulness of liver shear wave elastography (SWE) and shear wave dispersion (SWD) imaging in diagnosing and monitoring veno-occlusive disease in pediatric patients.

MATERIALS AND METHODS

We conducted a prospective cohort study at a single tertiary hospital from March 2021 to April 2022. The study protocol included four ultrasound (US) sessions: a baseline US and three follow-up US after hematopoietic stem cell transplantation. Clinical criteria, including the European Society for Blood and Marrow Transplantation criteria, were used to diagnose veno-occlusive disease. We compared clinical factors and US parameters between the veno-occlusive disease and non-veno-occlusive disease groups. The diagnostic performance of US parameters for veno-occlusive disease was assessed by plotting receiver operating characteristic (ROC) curves. We describe temporal changes in US parameters before and after veno-occlusive disease diagnosis.

RESULTS

Among the 38 participants (mean age 10.7 years), eight developed veno-occlusive disease occurring 17.0 ± 5.2 days after hematopoietic stem cell transplantation. Liver stiffness, as measured by SWE (15.0 ± 6.2 kPa vs. 5.8 ± 1.8 kPa; P<0.001), and viscosity, as assessed with SWD (17.7 ± 3.1 m/s/kHz vs. 14.3 ± 2.8 m/s/kHz; P=0.015), were significantly higher in the veno-occlusive disease group compared to the non-veno-occlusive disease group at the time of diagnosis. Liver stiffness demonstrated the highest area under the ROC (AUROC) curves at 0.960, with an optimal predictive value of >6.5 kPa, resulting in sensitivity and specificity of 100% and 83.3%, respectively. Viscosity demonstrated an AUROC of 0.783, with an optimal cutoff value of 13.9 m/s/kHz for predicting veno-occlusive disease, with a sensitivity of 100% and specificity of 53.3%, respectively. Liver stiffness increased with disease severity and decreased during post-treatment follow-up.

CONCLUSION

SWE may be a promising technique for early diagnosis and severity prediction of veno-occlusive disease. Furthermore, liver viscosity assessed by SWD may serve as an additional marker of veno-occlusive disease.

Post-allogeneic Hematopoietic Stem Cell Transplantation Portal Hypertension Not Associated with Liver Cirrhosis, Veno-occlusive Disease, or Graft-versus-host Disease

We herein report a rare case of idiopathic portal hypertension (IPH)-like disease that developed after allogeneic hematopoietic stem cell transplantation (allo-HSCT). A 53-year-old woman who underwent allo-HSCT for acute myeloid leukemia showed portal hypertension with radiological and histopathological findings consistent with IPH, distinct from veno-occlusive disease (VOD) and graft-versus-host disease (GVHD) of the liver. This case highlights the importance of considering IPH-like disease as a potential cause of portal hypertension after allo-HSCT. Awareness of this complication can aid in the early diagnosis and appropriate management of patients post allo-HSCT.

Evaluation of Circulating Endothelial Cells as Direct Marker of Endothelial Damage in Allo-Transplant Recipients at High Risk of Hepatic Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome

Sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD), is a rare but potentially fatal complication following allogenic hematopoietic cell transplantation (allo-HCT). Timely identification of SOS/VOD to allow for prompt treatment is critical, but identifying a VOD-predictive biomarker remains challenging. Given the pivotal role of endothelial dysfunction in SOS/VOD pathophysiology, the CECinVOD study prospectively evaluated levels of circulating endothelial cells (CECs) in patients undergoing allo-HCT with a myeloablative conditioning (MAC) regimen to investigate the potential of CEC level in predicting and diagnosing SOS/VOD. A total of 150 patients from 11 Italian bone marrow transplantation units were enrolled. All participants were age >18 years and received a MAC regimen, putting them at elevated risk of developing SOS/VOD. Overall, 6 cases of SOS/VOD (4%) were recorded. CECs were detected using the Food and Drug Administration-approved CellSearch system, an immunomagnetic selection-based platform incorporating ferrofluid nanoparticles and fluorescent-labeled antibodies, and were defined as CD146+, CD105+, DAPI+, or CD45-. Blood samples were collected at the following time points: before (T0) and at the end of conditioning treatment (T1), at neutrophil engraftment (T2), and at 7 to 10 days postengraftment (T3). For patients who developed VOD, additional samples were collected at any suspected or proven VOD onset (T4) and weekly during defibrotide treatment (T5 to T8). A baseline CEC count >17/mL was associated with an elevated risk of SOS/VOD (P = .04), along with bilirubin level >1.5 mg/mL and a haploidentical donor hematopoietic stem cell source. Postconditioning regimen (T1) CEC levels were elevated (P = .02), and levels were further increased at engraftment (P < .0001). Additionally, patients developing SOS/VOD after engraftment, especially those with late-onset SOS/VOD, showed a markedly higher relative increase (>150%) in CEC count. Multivariate analysis supported these findings, along with a high Endothelial Activation and Stress Index (EASIX) score at engraftment (T2). Finally, CEC kinetics corresponded with defibrotide treatment. After the start of therapy (T4), CEC levels showed an initial increase in the first week (T5), followed by a progressive decrease during VOD treatment (T6 and T7) and a return to pre-SOS/VOD onset levels at resolution of the complication. This prospective multicenter study reveals a low incidence of SOS/VOD in high-risk patients compared to historical data, in line with recent reports. The results from the CECinVOD study collectively confirm the endothelial injury in allo-HCT and its role in in the development of SOS/VOD, suggesting that CEC level can be a valuable biomarker for diagnosing SOS/VOD and identifying patients at greater risk of this complication, especially late-onset SOS/VOD. Furthermore, CEC kinetics may support treatment strategies by providing insight into the optimal timing for discontinuing defibrotide treatment.

Genetic Susceptibility in Endothelial Injury Syndromes after Hematopoietic Cell Transplantation and Other Cellular Therapies: Climbing a Steep Hill

Hematopoietic stem cell transplantation (HSCT) remains a cornerstone in the management of patients with hematological malignancies. Endothelial injury syndromes, such as HSCT-associated thrombotic microangiopathy (HSCT-TMA), veno-occlusive disease/sinusoidal obstruction syndrome (SOS/VOD), and capillary leak syndrome (CLS), constitute complications after HSCT. Moreover, endothelial damage is prevalent after immunotherapy with chimeric antigen receptor-T (CAR-T) and can be manifested with cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS). Our literature review aims to investigate the genetic susceptibility in endothelial injury syndromes after HSCT and CAR-T cell therapy. Variations in complement pathway- and endothelial function-related genes have been associated with the development of HSCT-TMA. In these genes, CFHR5, CFHR1, CFHR3, CFI, ADAMTS13, CFB, C3, C4, C5, and MASP1 are included. Thus, patients with these variations might have a predisposition to complement activation, which is also exaggerated by other factors (such as acute graft-versus-host disease, infections, and calcineurin inhibitors). Few studies have examined the genetic susceptibility to SOS/VOD syndrome, and the implicated genes include CFH, methylenetetrahydrofolate reductase, and heparinase. Finally, specific mutations have been associated with the onset of CRS (PFKFB4, CX3CR1) and ICANS (PPM1D, DNMT3A, TE2, ASXL1). More research is essential in this field to achieve better outcomes for our patients.

Chinese guideline for the diagnosis and treatment of drug-induced liver injury: an update

Drug-induced liver injury (DILI) is an important adverse drug reaction that can lead to acute liver failure or even death in severe cases. Currently, the diagnosis of DILI still follows the strategy of exclusion. Therefore, a detailed history taking and a thorough and careful exclusion of other potential causes of liver injury is the key to correct diagnosis. This guideline was developed based on evidence-based medicine provided by the latest research advances and aims to provide professional guidance to clinicians on how to identify suspected DILI timely and standardize the diagnosis and management in clinical practice. Based on the clinical settings in China, the guideline also specifically focused on DILI in chronic liver disease, drug-induced viral hepatitis reactivation, common causing agents of DILI (herbal and dietary supplements, anti-tuberculosis drugs, and antineoplastic drugs), and signal of DILI in clinical trials and its assessment.

Utility of liver stiffness measurement in the diagnosis of sinusoidal obstruction syndrome/veno-occlusive disease after hematopoietic stem cell transplantation

PURPOSE

We aimed to assess the role of liver stiffness measurement (LSM), evaluated using transient elastography (TE), for the diagnosis of sinusoidal obstruction syndrome (SOS)/veno-occlusive disease (VOD), a complication of hematopoietic stem cell transplantation (HSCT).

METHODS

In this retrospective study, ultrasonography (US) and LSM were performed on 86 adult patients (55 men and 31 women) undergoing HSCT between January 2016 and December 2022. Characteristics and changes in liver stiffness (LS) were compared between patients with and without SOS/VOD.

RESULTS

Of the 86 patients, 14 were diagnosed with SOS/VOD. A significant increase in LS (ranging from 12.6 to 55.1 kPa, median 23.8 kPa) compared to pre-HSCT values was observed in all patients who developed SOS/VOD. The area under the receiver operating characteristic curve (AUROC) for the diagnosis of SOS/VOD was 0.9663 (0.933-0.995) for LS ≥ 17.4 kPa after HSCT. Post-transplant LS exceeded 17.4 kPa in all 14 patients in the SOS/VOD group (100%) and in seven patients in the non-SOS/VOD group (9.7%). The sensitivity and specificity were 100% and 90.3%, respectively. AUROC for the diagnosis of SOS/VOD was 0.973 (0.943-1.000) for LS increase ≥  + 12.6 kPa from baseline after HSCT. The change of ≥  + 12.6 kPa from baseline was observed in all 14 patients in the SOS/VOD group (100%) and in four patients in the non-SOS/VOD group (5.6%). The sensitivity and specificity were 100% and 94.4%, respectively.

CONCLUSION

LSM using TE may contribute to establishing the diagnosis of SOS/VOD after HSCT.

Transfusion Support in Hematopoietic Stem Cell Transplantation: A Contemporary Narrative Review

Hematopoietic stem cell transplantation (HSCT) is a cornerstone of modern medical practice, and can only be performed safely and effectively with appropriate transfusion medicine support. Patients undergoing HSCT often develop therapy-related cytopenia, necessitating differing blood product requirements in the pre-, peri-, and post-transplant periods. Moreover, ensuring optimal management for patients alloimmunized to human leukocyte antigens (HLA) and/or red blood cell (RBC) antigens, as well as for patients receiving ABO-incompatible transplants, requires close collaboration with transfusion medicine and blood bank professionals. Finally, as updated transfusion guidelines and novel blood product modifications emerge, the options available to the transplant practitioner continue to expand. Herein, we detail contemporary blood transfusion and transfusion medicine practices for patients undergoing HSCT.

sVEGF-R1 in acute non-infectious toxicity syndromes after pediatric allogeneic hematopoietic stem cell transplantation

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (HSCT) is challenged by acute non-infectious toxicities, including sinusoidal obstruction syndrome (SOS), engraftment syndrome (ES) and capillary leak syndrome (CLS) among others. These complications are thought to be driven by a dysfunctional vascular endothelium, but the pathophysiological mechanisms remain incompletely understood, and the diagnoses are challenged by purely clinical diagnostic criteria that are partly overlapping, limiting the possibilities for progress in this field. There is, however, increasing evidence suggesting that these challenges may be met through the development of diagnostic biomarkers to improve diagnostic accuracy of pathogenetically homogenous entities, improved pre-transplant risk assessment and the early identification of patients with increased need for specific treatment. Soluble vascular endothelial growth factor receptor-1 (sVEGF-R1) is emerging as an important biomarker of endothelial damage in patients with trauma and sepsis but has not been studied in HSCT.

OBJECTIVES

To investigate sVEGF-R1 as a marker of endothelial damage in pediatric HSCT patients by exploring associations with SOS, CLS, ES, and acute graft-versus-host disease (aGvHD).

METHODS

We prospectively included 113 children undergoing myeloablative HSCT and measured sVEGF-R1 in plasma samples obtained weekly during the early period of transplantation and 3 months post-transplant.

RESULTS

All over, sVEGF-R1 levels were significantly increased from day +7 after graft infusion, peaking at day +30, most pronounced in patients receiving busulfan. Patients considered to be at increased risk of SOS and therefore commenced on prophylactic defibrotide had significantly elevated levels of sVEGF-R1 before start of conditioning (446 pg/mL vs. 281 pg/mL, p = 0.0035), and this treatment appeared to stabilize sVEGF-R1 levels compared to patients not treated with defibrotide. Thirteen (11.5%) children meeting the modified Seattle criteria for SOS at median day +8 (1-18), had significantly elevated sVEGF-R1 levels on day +14 (489 pg/mL vs. 327 pg/mL, p = 0.007). In contrast. sVEGF-R1 levels in the much broader group of patients (45.1%) meeting EBMT-SOS criteria, including patients with very mild disease, did not overall differ in sVEGF-R1 levels, but higher sVEGF-R1 levels were seen in EBMT-SOS patients with an increased need for diuretic treatment. Importantly, sVEGF-R1 levels were not associated with ES and CLS but were significantly increased on day +30 in patients with grade III-IV aGvHD (OR = 4.2 pr. quartile, p = 0.023).

CONCLUSION

VEGF-R1 levels are found to be increased in pediatric patients developing SOS, reflecting the severity of morbidity. sVEGF-R1 were unassociated with both CLS and ES. The potential of sVEGF-R1 as a clinically useful biomarker for SOS should be further explored to improve pre-transplant SOS-risk assessment, SOS-severity grading, and to guide treatment.

Primary Budd-Chiari syndrome versus sinusoidal obstruction syndrome: a review

Budd-Chiari syndrome (BCS) and sinusoidal obstruction syndrome (SOS) are two major vascular disorders of the liver, of which both can cause portal hypertension related complications, but their locations of obstruction are different. BCS refers to the obstruction from the hepatic vein to the junction between the inferior vena cava and right atrium, which is the major etiology of post-sinusoidal portal hypertension; by comparison, SOS is characterized as the obstruction at the level of hepatic sinusoids and terminal venulae, which is a cause of sinusoidal portal hypertension. Both of them can cause hepatic congestion with life-threatening complications, especially acute liver failure and chronic portal hypertension, and share some similar features in terms of imaging and clinical presentations, but they have heterogeneous risk factors, management strategy, and prognosis. Herein, this paper reviews the current evidence and then summarizes the difference between primary BCS and SOS in terms of risk factors, clinical features, diagnosis, and treatment.

How I treat transplant-eligible patients with myelofibrosis

Despite the approval of Janus kinase inhibitors and novel agents for patients with myelofibrosis (MF), disease-modifying responses remain limited, and hematopoietic stem cell transplantation (HSCT) remains the only potentially curative treatment option. The number of HSCTs for MF continues to increase worldwide, but its inherent therapy-related morbidity and mortality limit its use for many patients. Furthermore, patients with MF often present at an older age, with cytopenia, splenomegaly, and severe bone marrow fibrosis, posing challenges in managing them throughout the HSCT procedure. Although implementation of molecular analyses enabled improved understanding of disease mechanisms and subsequently sparked development of novel drugs with promising activity, prospective trials in the HSCT setting are often lacking, making an evidence-based decision process particularly difficult. To illustrate how we approach patients with MF with respect to HSCT, we present 3 different clinical scenarios to capture relevant aspects that influence our decision making regarding indication for, or against, HSCT. We describe how we perform HSCT according to different risk categories and, furthermore, discuss our up-to-date approach to reduce transplant-related complications. Last, we show how to harness graft-versus-MF effects, particularly in the posttransplant period to achieve the best possible outcomes for patients.

Myeloablative Dose of Busulfan and Fludarabine Combined with In Vivo T Cell Depletion Is Safe and Effective Conditioning for Acute Myeloid Leukemia and Myelodysplastic Syndrome Patients

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative strategy for acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). The prediction of transplantation-related mortality (TRM) using the Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) score and an arbitrary upper age limit of 55 years for administering myeloablative conditioning (MAC) are common strategies to ensure a safe procedure. The use of reduced-toxicity conditioning regimens is an additional approach to providing safe and effective myeloablation. Herein we report the outcome of AML and MDS patients conditioned with fludarabine and a myeloablative dose of busulfan (FB4) stratified by age and HCT-CI score. The primary objective was overall survival (OS) for patients age ≥55 years. Secondary objectives were total OS, TRM, graft-versus-host disease (GVHD), and GVHD, relapse-free survival (GRFS). The 2 year OS was 72% in patients age <55 and 51% in patients age ≥55. In patients age ≥55 with an HCT-CI <2, the estimated 2 year OS was 64%, with median OS not reached. In those with HCT-CI ≥2, the 2-year OS was 43%, with a median OS of 14 months. The total cumulative incidence of relapse was 30% regardless of age or HCT-CI score. FB4 conditioning regimen offers a high rate of prolonged remission with a relapse rate similar to that reported in previous studies. These positive outcomes suggest that this conditioning platform can be offered to patients age ≥55 years in the absence of comorbidities, and that age should not be the sole determinant of conditioning intensity.

Increased Body Mass Index Augments Endothelial Injury and Clinical Outcomes after Hematopoietic Stem Cell Transplantation

Higher body mass index (BMI) is characterized as a chronic inflammatory state with endothelial dysfunction. Endothelial injury after allogeneic hematopoietic stem cell transplantation (allo-HSCT) puts patients at risk for such complications as transplantation-associated thrombotic microangiopathy (TA-TMA) and acute graft-versus-host-disease (aGVHD). To evaluate the impact of increased BMI on endothelial injury after allo-HSCT in pediatric and young adult patients, we conducted a retrospective cohort study evaluating 476 consecutive allo-HSCT children and young adult recipients age 0 to 20 years. Our analysis was subdivided based on distinct age categories (<2 years and 2 to 20 years). BMI was considered as a variable but was also expressed in standard deviations from the mean adjusted for age and sex (z-score), based on established criteria from the World Health Organization (age <2 years) and the Centers for Disease Control and Prevention (age 2 to 20 years) to account for differences associated with age. Primary endpoints included the incidences of TA-TMA and aGVHD. Increased BMI z-score was associated with TA-TMA after allo-HSCT in patients age <2 years (median, 18.1; IQR, 17 to 20; P = .006) and in patients age 2 to 20 years (median, 18.7; IQR, 16 to 21.9; P = .02). Higher BMI z-score correlated with TA-TMA risk in both age groups, with a BMI z-score of .9 in the younger cohort and .7 (IQR, -.4 to 1.6; P = .04) in the older cohort. Increased BMI z-score was associated with an increased risk of TA-TMA in a multivariate analysis of the entire cohort (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.05 to 1.37; P = .008). Multivariate analysis also demonstrated that patients with BMI in the 85th percentile or greater had an increased risk of developing TA-TMA compared to those with a lower BMI percentile (OR, 2.66; 95% CI, 1.62 to 4.32; P < .001). Baseline and day +7 ST2 levels were elevated in subjects with TA-TMA compared to those without TA-TMA in both age groups. Baseline sC5b-9 concentration was not correlated with BMI z-score, but sC5b-9 concentration was increased markedly by 7 days post-allo-HSCT in patients age <2 years who later developed TA-TMA compared to those who never developed TA-TMA (P = .001). The median BMI z-score was higher for patients with aGVHD compared to patients without aGVHD (.7 [range, -3.9 to 3.9] versus .2 [range, -7.8 to 5.4]; P = .03). We show that high BMI is associated with augmented risk of endothelial injury after HSCT, specifically TA-TMA. These data identify a high-risk population likely to benefit from early interventions to prevent endothelial injury and prompt treatment of established endothelial injury.

Current incidence, severity, and management of veno-occlusive disease/sinusoidal obstruction syndrome in adult allogeneic HSCT recipients: an EBMT Transplant Complications Working Party study

The current incidence, diagnostic policy, management, and outcome of VOD/SOS at EBMT centers were studied. All centers that had performed allogeneic HSCTs in adult patients within one defined year were invited to the study. Seventy-one centers participated with a total of 2886 allogeneic transplantations and 93 cases of VOD/SOS in 2018. The cumulative incidence of VOD/SOS at day 21 was 1.8% and at day 100 2.4%. Of 67 cases with detailed data, 52 were classical and 15 (22%) late onset (>day 21). According to the EBMT criteria, 65/67 patients had at least two VOD/SOS risk factors. The severity grades were: mild 0, moderate 3, severe 29, very severe 35. Fifty-four patients were treated with defibrotide. VOD/SOS resolved in 58% of the patients, 3/3 with moderate, 22/28 with severe, and 12/33 with very severe grade (p < 0.001). By day 100, 57% of the patients were alive; 3/3 with moderate, 22/29 with severe, and 13/35 with very severe VOD/SOS (p = 0.002). In conclusion, the incidence of VOD/SOS was low. Severe and very severe grades dominated. Very severe grade predicted poor outcome compared to severe grade further supporting the concept of early diagnosis and treatment to avoid a dismal outcome.

Constructing training set using distance between learnt graphical models of time series data on patient physiology, to predict disease scores

Interventional endeavours in medicine include prediction of a score that parametrises a new subject's susceptibility to a given disease, at the pre-onset stage. Here, for the first time, we provide reliable learning of such a score in the context of the potentially-terminal disease VOD, that often arises after bone marrow transplants. Indeed, the probability of surviving VOD, is correlated with early intervention. In our work, the VOD-score of each patient in a retrospective cohort, is defined as the distance between the (posterior) probability of a random graph variable-given the inter-variable partial correlation matrix of the time series data on variables that represent different aspects of patient physiology-and that given such time series data of an arbitrarily-selected reference patient. Such time series data is recorded from a pre-transplant to a post-transplant time, for each patient in this cohort, though the data available for distinct patients bear differential temporal coverage, owing to differential patient longevities. Each graph is a Soft Random Geometric Graph drawn in a probabilistic metric space, and the computed inter-graph distance is oblivious to the length of the time series data. The VOD-score learnt in this way, and the corresponding pre-transplant parameter vector of each patient in this retrospective cohort, then results in the training data, using which we learn the function that takes VOD-score as its input, and outputs the vector of pre-transplant parameters. We model this function with a vector-variate Gaussian Process, the covariance structure of which is kernel parametrised. Such modelling is easier than if the score variable were the output. Then for any prospective patient, whose pre-transplant variables are known, we learn the VOD-score (and the hyperparameters of the covariance kernel), using Markov Chain Monte Carlo based inference.

HokUS-10 scoring system predicts the treatment outcome for sinusoidal obstruction syndrome after allogeneic hematopoietic stem cell transplantation

Hepatic sinusoidal obstruction syndrome (SOS) is a severe and life-threatening complication after allogeneic hematopoietic stem cell transplantation (HSCT). We conducted a multi-center retrospective study to evaluate the utility of our ultrasonographic scoring system for the diagnosis of SOS (HokUS-10) in predicting SOS-related mortality (SOS-RM). We analyzed a total of 42 patients who developed SOS after HSCT. The cumulative incidences of SOS-RM, non-relapse mortality (NRM), and overall survival at day 180 after the diagnosis of SOS were 26.4%, 28.8% and 54.5%, respectively. The area under the receiver operating characteristic curve analysis showed that the optimal cut-off value of HokUS-10 total score to predict SOS-RM was 8 points after the treatment of SOS. In the individual HokUS-10 score, ascites and portal vein flow-related scores (PV mean velocity and PV flow direction) after the treatment of SOS were shown as significant risk factors for SOS-RM. Our study suggested that US findings after the treatment can predict the treatment outcomes for SOS.

Role of Defibrotide in the Prevention of Murine Model Graft-versus-Host Disease after Allogeneic Hematopoietic Cell Transplantation

Graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Vascular endothelial cells are entirely exposed and damaged during the pathogenesis of acute GVHD (aGVHD). Defibrotide (DF) is a mixture of single-stranded oligonucleotides that has several pharmacologic effects that contribute to its endothelial protective properties. B10.BR mice were conditioned, followed by the infusion of donor C57BL/6J T cell-depleted bone marrow cells with or without splenocytes. The mice were either treated with DF or appropriate controls daily for the first week and then 3 times per week thereafter. Allogeneic DF-treated recipients demonstrated significantly better survival with reduced clinical GVHD. Significantly reduced organ pathology in the gut was associated with significantly decreased T cell infiltration in the ileum and colon on day +28. Serum cytokine analysis revealed significantly reduced levels of TNF and IL-6 at day +7 and of TNF at day +28 in allogeneic DF-treated recipients. Significantly reduced levels of ICAM-1 and angiopoietin-2 in serum and reduced VCAM-1 and HCAM levels in the ileum and colon of allogeneic DF-treated recipients were observed. Improved survival was seen in the graft-versus-leukemia (GVL) model (C3H.SW into C57BL/6J mice with C1498-luc). Through its anti-inflammatory and endothelial protective effects, DF treatment reduces the severity of aGVHD while not impairing GVL activity.

Transjugular Intrahepatic Portosystemic Shunt is effective to treat portal hypertension due to sinusoidal obstructive syndrome

Transjugular Intrahepatic Portosystemic Shunt (TIPS) is an established procedure for the complications of portal hypertension, such as variceal bleeding, refractory ascites and hepatic hydrothorax. We report an original case of a renal transplant patient successfully treated with TIPS for portal hypertension due to sinusoidal obstructive syndrome (SOS) induced by azathioprine (AZA). By reporting this case, we wish to draw the attention of healthcare professionals managing organ transplant patients, especially nephrologists, to the possible occurrence of liver toxicity due to AZA, and to emphasize the role of TIPS as an effective therapeutic option for portal hypertension-related complications.

The Use of SARS-CoV-2-Positive Donors in Hematopoietic Stem Cell Transplantation

BACKGROUND

Since 2019, the SARS-CoV-2 pandemic has become a global issue due to its high fatality rate. Over time, the characteristics of the virus have evolved and led to the creation of an omicron strain with higher infectivity but a significantly decreased fatality rate. For patients in urgent need of hematopoietic stem cell transplantation (HSCT), whether the SARS-CoV-2 infection status of donors has a significant impact on HSCT recipients should be clarified.

METHODS

To estimate the transplantation risk of SARS-CoV-2-positive donors, 24 patients who underwent HSCT from December 1, 2022 to January 30, 2023 were retrospectively included. The ratio of the observation group (SARS-CoV-2-positive donors, n = 12) to the control group (SARS-CoV-2-negative donors, n = 12) was 1:1. We observed the time of hematopoietic reconstruction, donor chimerism, severe infection, acute graft vs host disease, and hepatic vein occlusion disease during hematopoietic reconstruction.

RESULTS

In the observation group, the average time of myeloid hematopoietic reconstruction was 11.58 days, and in the control group, it was 12.17 days (P = .3563 [>.05]). On average, all patients achieved a 90% donor chimerism rate of +13.58 (±4.5) days (P = .5121 [>.05]). The average percentage of patients that achieved successful hematopoietic reconstruction was 96.75% in the observation group and 96.31% in the control group (P = .7819 [>.05]). A total of 6 adverse events occurred during this study: 3 in the observation group and 3 in the control group.

CONCLUSIONS

Our preliminary results showed favorable short-term outcomes in recipients of SARS-CoV-2-positive HCST donors.

Ibrutinib Induces a Dramatic Improvement for Idiopathic Refractory Ascites Following Allogeneic Hematopoietic Cell Transplantation

We herein report a case of idiopathic refractory ascites following allogeneic hematopoietic cell transplantation that was successfully treated with ibrutinib. A 39-year-old man presented with massive transudative ascites. Despite a high portal venous pressure, the liver histology showed traces of alloreactivity inconsistent with veno-occlusive disease/sinusoidal obstructive syndrome. Ibrutinib was administered for ascites possibly secondary to portal hypertension associated with the alloreactivity. The ascites dramatically improved, and the portal venous pressure was reduced. This case may help clarify the mechanism through which refractory ascites develops after allogeneic hematopoietic cell transplantation and establish appropriate treatment protocols.

Liver Pathology After Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation is used to treat a variety of hematologic malignancies and autoimmune conditions. The immunosuppressive medications as well as other therapies used both before and after transplantation leave patients susceptible to a wide spectrum of complications, including liver injury. Causes for liver damage associated with stem cell transplantation include sinusoidal obstruction syndrome, graft-versus-host disease, iron overload, and opportunistic infection. Here, the authors review the clinical and pathological findings of these etiologies of liver injury and provide a framework for diagnosis.

Evolving Understanding of Noncirrhotic Portal Hypertension

Although cirrhosis is one of the most common causes of portal hypertension, noncirrhotic portal hypertension can result from hemodynamic perturbations occurring in the prehepatic, intrahepatic, and posthepatic circulation. Intrahepatic portal hypertension can be further subclassified relative to the hepatic sinusoids as presinusoidal, sinusoidal, and postsinusoidal. For many of these differential diagnoses, the etiology is known but the cause of idiopathic noncirrhotic portal hypertension, recently included in porto-sinusoidal vascular disease (PSVD), remains poorly understood. Herein, we discuss the diagnostic pathological features of noncirrhotic portal hypertension, with an emphasis on PSVD.

Immunotherapy in hematologic malignancies: achievements, challenges and future prospects

The immune-cell origin of hematologic malignancies provides a unique avenue for the understanding of both the mechanisms of immune responsiveness and immune escape, which has accelerated the progress of immunotherapy. Several categories of immunotherapies have been developed and are being further evaluated in clinical trials for the treatment of blood cancers, including stem cell transplantation, immune checkpoint inhibitors, antigen-targeted antibodies, antibody-drug conjugates, tumor vaccines, and adoptive cell therapies. These immunotherapies have shown the potential to induce long-term remission in refractory or relapsed patients and have led to a paradigm shift in cancer treatment with great clinical success. Different immunotherapeutic approaches have their advantages but also shortcomings that need to be addressed. To provide clinicians with timely information on these revolutionary therapeutic approaches, the comprehensive review provides historical perspectives on the applications and clinical considerations of the immunotherapy. Here, we first outline the recent advances that have been made in the understanding of the various categories of immunotherapies in the treatment of hematologic malignancies. We further discuss the specific mechanisms of action, summarize the clinical trials and outcomes of immunotherapies in hematologic malignancies, as well as the adverse effects and toxicity management and then provide novel insights into challenges and future directions.

Inotuzumab ozogamicin in B-cell precursor acute lymphoblastic leukemia: efficacy, toxicity, and practical considerations

Inotuzumab ozogamicin (InO) is an antibody drug conjugate composed of a humanized monoclonal antibody targeting the cell surface receptor CD22 coupled to a cytotoxic calicheamicin payload via an acid labile linker. InO has shown significant activity in relapsed and refractory B-cell precursor acute lymphoblastic leukemia (BCP-ALL) in both single agent and combination chemotherapy regimens in adult and pediatric trials. Its use in newly diagnosed elderly patients has also been established while clinical trials investigating its use in newly diagnosed pediatric patients and fit adults are ongoing. Notable toxicities include sinusoidal obstruction syndrome (SOS), particularly in patients who undergo hematopoietic stem cell transplantation (HSCT) after InO as well as myelosuppression and B-cell aplasia which confer increased infection risk, particularly in combination with cytotoxic chemotherapy. In the relapsed/refractory (R/R) setting, the planned subsequent curative therapy modality must be considered when using InO to mitigate SOS risk if proceeding to HSCT and account for potential B-cell aplasia if proceeding to chimeric antigen receptor CAR-T therapy. Studies exploring mechanisms of resistance or failure of InO are ongoing but modulation or loss CD22 expression, alternative CD22 splicing, and high Bcl-2 expression have been implicated. In this review, we will summarize the currently available data on InO, with an emphasis on pediatric trials, and explore future directions including combinatorial therapy.

Cardio-oncology and transplantation for acute myeloid leukemia

Despite the rapidly evolving treatment landscape for acute myeloid leukemia (AML), allogeneic hematopoietic cell transplantation (allo-HCT) remains an important and potentially curative treatment option for many high-risk AML patients. Cardiovascular disease is an important competing risk throughout allo-HCT and a key driver of morbidity and mortality long after treatment. Cardio-oncology is a new discipline in cardiology which provides multidisciplinary care and expertise to complex cancer patients with the aims of optimizing cardiovascular health plus monitoring and treating potential cardiotoxicity related to cancer treatments. As allogeneic HCT techniques get more sophisticated there will be an increase in transplant eligible older patients with a rise in comorbidities including established cardiovascular disease highlighting the need for close collaboration with cardio-oncology specialists from the time of diagnosis through late survivorship.

Thymosin β4 exerts cytoprotective function and attenuates liver injury in murine hepatic sinusoidal obstruction syndrome after hematopoietic stem cell transplantation

Hepatic sinusoidal obstruction syndrome (HSOS) is one of the life-threatening complications that may occur after hematopoietic stem cell transplantation (HSCT). Hepatic sinusoidal endothelial cells (HSECs) injury and liver fibrosis are key mechanisms of HSOS. Thymosin β4 (Tβ4) is an active polypeptide that functions in a variety of pathological and physiological states such as inflammation regulation, anti-apoptosis and anti-fibrosis. In this study, we found that Tβ4 can stimulate HSECs proliferation, migration and tube formation in vitro via activation of pro-survival signaling AKT (protein kinase B). In addition, Tβ4 resisted γ irradiation-induced HSECs growth arrest and apoptosis in parallel with upregulation of anti-apoptotic protein B-cell lymphoma-extra-large (Bcl-xL) and B-cell lymphoma-2 (Bcl-2), which may be associated with activation of AKT. More importantly, Tβ4 significantly inhibited irradiation-induced proinflammatory cytokines in parallel with negative regulation of TLR4/MyD88/NF-κB and MAPK p38. Meanwhile, Tβ4 reduced intracellular reactive oxygen species production and upregulated antioxidants in HSECs. Additionally, Tβ4 inhibited irradiation-induced activation of hepatic stellate cells via downregulation expression of fibrogenic markers α-SMA, PAI-1 and TGF-β. In a murine HSOS model, levels of circulating alanine aminotransferase, aspartate aminotransferase, total bilirubin, and pro-inflammatory cytokines IL-6, IL-1β and TNF-α were significantly reduced after administration of Tβ4 peptide; further, Tβ4 treatment successfully ameliorated HSECs injury, inflammatory damage and fibrosis of murine liver. Taken together, Tβ4 stimulates proliferation and angiogenesis of HSECs, exerts cytoprotective effect and attenuates liver injury in murine HSOS model, which could be a potential strategy to prevent and treat HSOS after HSCT.