Cerebral thrombotic complications in adolescent leukemia/lymphoma patients treated with L-asparaginase-containing chemotherapy

Thrombosis Complications in Pediatric Acute Lymphoblastic Leukemia: Risk Factors, Management, and Prevention: Is There Any Role for Pharmacologic Prophylaxis?

Pediatric acute lymphoblastic leukemia (ALL) has achieved close to 90% cure rates through extensive collaborative and integrative molecular research, clinical studies, and advances in supportive care. Despite this high achievement, venous thromboembolic complications (VTE) remain one of the most common and potentially preventable therapy-associated adverse events in ALL. The majority of thromboses events involve the upper central venous system which is related to the use and location of central venous catheters (CVC). The reported rates of symptomatic and asymptomatic CVC-related VTE range from 2.6 to 36.7% and 5.9 to 43%, respectively. Thrombosis can negatively impact not only disease-free survival [e.g., therapy delays and/or interruption, omission of chemotherapy agents (e.g., asparaginase therapy)] but also can result in long-term adverse effects that can impair the quality of life of ALL survivors (e.g., post-thrombotic syndrome, central nervous system (CNS)-thrombosis related complications: seizures, neurocognitive deficits). In this review, will discuss thrombosis pathophysiology in pediatric ALL, risk factors, treatment, and prevention strategies. In addition, the recently published clinical efficacy and safety of direct oral anticoagulants (DOACs) use in thrombosis treatment, and their potential role in primary/secondary thrombosis prevention in pediatric patients with ALL will be discussed. Future clinical trials involving the use of these novel oral anticoagulants should be studied in ALL not only for primary thrombosis prevention but also in the treatment of thrombosis and its secondary prevention. These future research findings could potentially extrapolate to VTE prevention strategies in other pediatric cancer diagnoses and children considered at high risk for VTE.

Anticoagulation treatment and prophylactic edoxaban for cerebral sinus venous thrombosis in an adolescent with acute lymphoblastic leukemia

Pediatric acute lymphoblastic leukemia regimens include large L-asparaginase dosages and steroids, which are associated with an increased risk of venous thromboemboli in adolescents and young adults. Herein, we report the case of an 18-year-old male with acute lymphoblastic leukemia, who was treated with the pediatric regimen, in which edoxaban was employed as a prophylaxis against cerebral sinus venous thrombosis. The event happened on day 20 of induction therapy, when brain magnetic resonance imaging demonstrated a cerebral sinus venous thrombosis in the superior sagittal sinus. Anticoagulation therapy was initiated, and the patient's symptoms disappeared 3 days later. The induction therapy was restarted after an interruption of 16 days, and the consolidation therapies, which included L-asparaginase and steroids, were completed. Edoxaban was administered as a prophylaxis during the consolidation therapy. There were no further adverse events. Edoxaban could be an effective prophylaxis for coagulation complications in adolescents and young adults with acute lymphoblastic leukemia.

Cerebral Venous Thrombosis in the Setting of Malignancy: Case Report and Review of the Literature

Cerebral venous thrombosis (CVT) is a rare condition that can be difficult to diagnose due to its vague and nonspecific symptoms. It is even more unusual to identify CVT in association with malignancy. Given the rarity of this disease, treatment and management of CVT in the setting of malignancy is not well defined. This case report and review of the literature addresses the epidemiology, pathophysiology, and medical treatment for malignancy-related CVT.

Venous thromboembolism in a large cohort of children with acute lymphoblastic leukemia: Risk factors and effect on prognosis

BACKGROUND

Venous thromboembolism (VTE) is relatively common in children with acute lymphoblastic leukemia (ALL). Thrombotic risk factors in ALL are asparaginase and steroids. However, within the ALL populations treated on the same regimen, it is less clear which other risk factors play a role. Furthermore, few data are available on the effect of VTE on ALL outcomes.

METHODS

In 778 children (1-18 years) with newly diagnosed precursor-B-lineage or T-lineage ALL, treated in the Dutch Childhood Oncology Group (DCOG) ALL-10 protocol in the Netherlands (October 2004 to April 2013), we conducted a nested case control study with 59 VTE cases and 118 controls to identify risk factors for VTE.

RESULTS

Fifty-nine of 778 ALL patients developed VTE (7.6%), with cerebral venous sinus thrombosis (CVST) in 26 of 59 patients (44.1%). VTE occurred during induction treatment in 59.3% (n = 35) and in 40.7% (n = 24) during medium risk intensification. Conditional multivariable logistic regression analysis showed that age and ALL subtype were significantly associated with VTE (age ≥7 years: OR 2.72, 95% CI 1.33-5.57; ALL subtype T-ALL: OR 2.95, 95% CI 1.02-8.57). A multivariable Cox model showed no association between the occurrence of VTE and event free survival. In CVST patients, permanent disability was present in 34.6%.

CONCLUSION

Within this large pediatric ALL cohort, we demonstrated a high morbidity in CVST patients. Age ≥7 years at diagnosis and T-ALL subtype were the main risk factors for VTE, and should be considered in preventive strategies.

Increasing Incidence and Recurrence Rate of Venous Thromboembolism in Paediatric Oncology Patients in One Single Centre Over 25 Years

Venous thromboembolism (VTE) is a serious complication in paediatric oncology patients. To identify the incidence, risk factors and recurrence rate of VTE in paediatric oncology patients, an observational, retrospective cohort study of all consecutive children (≤18 years) with malignancies, treated at the Emma Children's Hospital Academic Medical Centre between January 1989 and December 2013, was done. A matched case-control study in children with lymphomas was performed, to identify thrombotic risk factors. Cumulative recurrence-free survival after first VTE was estimated by the Kaplan-Meier method. Of the 2,183 children included (male: female = 1.4:1.0; median age, 6.6 years) with cancer, 78 patients developed VTE (3.6%; 95% confidence interval [CI], 2.8-4.4). The incidence increased from 0.8% (4/478, 95% CI, 0.0-1.6) between 1989 and 1993 to 10.4% (44/423, 95% CI, 7.6-13.4) between 2009 and 2013. Independent risk factors for VTE were age ≥ 12 years, acute lymphoblastic leukaemia (ALL) and lymphoma. The case-control study in lymphoma patients showed a trend for increased VTE incidence in stage IV lymphoma. Twelve (15.4%) patients developed recurrent thrombosis, 7 patients while on therapeutic or prophylactic anticoagulation. The cumulative recurrence-free survival after first VTE was 88.5, 87.1 and 80.6% after 1, 5 and 10 years, respectively. In conclusion, we demonstrated an increasing incidence of VTE in children with malignancies, with age ≥ 12 years, ALL and lymphoma as independent risk factors. The elevated recurrence rate underlines the importance of full anticoagulant therapy and might warrant prophylactic anticoagulation after first VTE during cancer treatment.

An antithrombin replacement strategy during asparaginase therapy for acute lymphoblastic leukemia is associated with a reduction in thrombotic events

Thrombosis is a well-recognized complication of asparaginase therapy for acute lymphoblastic leukemia (ALL), associated with the depletion of antithrombin (AT). Following a high incidence of thrombotic episodes during induction therapy for ALL in our tertiary referral center, we prospectively instituted a protocol of AT replacement. Forty-five consecutive adolescents and adults with ALL treated with asparaginase-containing phase I induction protocols were included in this observational study. Fifteen received standard therapy with no replacement; the subsequent 30 were managed with the protocol described. One or more low AT levels (<70 iu/dl) were recorded in 76% of patients in the cohort managed using the protocol, resulting them in receiving an AT replacement. There was a significant reduction in the incidence of thrombosis with this strategy (0/30 vs. 5/15, p < 0.001). We suggest that such a strategy should be studied in a prospective randomized sub-study within the context of a national ALL trial.

L-asparaginase as a critical component to combat Acute Lymphoblastic Leukaemia (ALL): A novel approach to target ALL

L-asparaginase, an anti-leukaemic drug that has been approved for clinical use for many years in the treatment of childhood Acute Lymphoblastic Leukaemia (ALL), is obtained from bacterial origin (Escherichia coli and Erwinia carotovora). The efficacy of L-asparaginase has been discussed for the past 40 years, and an ideal substitute for the enzyme has not yet been developed. The early clearance from plasma (short half-life) and requirement for multiple administrations and hence frequent physician visits make the overall treatment cost quite high. In addition, a high rate of allergic reactions in patients receiving treatment with the enzyme isolated from bacterial sources make its clinical application challenging. For these reasons, various attempts are being made to overcome these barriers. Therefore, the present article reviews studies focused on seeking substitutes for L-asparaginase through alternative sources including bacteria, fungi, actinomycetes, algae and plants to overcome these limitations. In addition, the role of chemical modifications and protein engineering approaches to enhance the drug's efficacy are also discussed. Moreover, an overview has also been provided in the current review regarding the contradiction among various researchers regarding the significance of the enzyme's glutaminase activity.

Thrombotic complications in adult patients with lymphoma: a meta-analysis of 29 independent cohorts including 18 018 patients and 1149 events

Thrombotic complications in hematologic malignancies have important clinical implications. In this meta-analysis we sought to obtain accurate estimates of the thrombotic risk in lymphoma patients. Articles were searched in electronic databases and references. Eighteen articles were identified (29 cohorts, 18 018 patients and 1149 events). Pooled incidence rates (IRs) were calculated by the use of a method based on the exact maximum likelihood binomial distribution. The global IR of thrombosis was 6.4% (95% confidence interval [CI] 6.0%-6.8%). The global IRs of venous or arterial events were 5.3% (95% CI, 5.0%-5.7%) and 1.1% (95% CI, 0.9%-1.2%), respectively. The IR of thrombosis observed in subjects with non-Hodgkin lymphoma (NHL) was 6.5% (95% CI, 6.1%-6.9%), significantly greater than that observed for patients with Hodgkin lymphoma (4.7%; 95% CI, 3.9%-5.6%). Within NHL, patients with high-grade disease had a greater risk of events (IR 8.3%; 95% CI, 7.0%-9.9%) than low-grade disease (IR 6.3%; 95% CI, 4.5%-8.9%). This meta-analysis shows that the IR of thrombosis in lymphoma patients is quite high, especially in those with NHL at an advanced stage of the disease. These results may help better defining lymphoma populations at high thrombotic risk, to whom prophylactic approaches could be preferentially applied.

Anaphylaxis and superior vena cava thrombus in a pediatric patient with acute lymphoblastic leukemia

Pediatric patients with malignancies are at significant risk for complications from their underlying condition and medical therapy. Emergency medicine physicians must be quick to suspect life-threatening events, which can present insidiously. We describe a case of anaphylaxis and superior vena cava syndrome in an 18-year-old female patient after polyethylene glycol-conjugated asparaginase chemotherapy for acute lymphoblastic leukemia. Pertinent literature surrounding risk factors, diagnosis, and treatment is also reviewed.

L-Asparaginase: A Promising Chemotherapeutic Agent

This article comprises detailed information about L-asparaginase, encompassing topics such as microbial and plant sources of L-asparaginase, treatment with L-asparaginase, mechanism of action of L-asparaginase, production, purification, properties, expression and characteristics of l-asparaginase along with information about studies on the structure of L-asparaginase. Although L-asparaginase has been reviewed by Savitri and Azmi (2003), our effort has been to include recent and updated information about the enzyme covering new aspects such as structural modification and immobilization of L-asparaginase, recombinant L-asparaginase, resistance to L-asparaginase, methods of assay of L-asparagine and L-asparaginase activity using the biosensor approach, L-asparaginase activity in soil and the factors affecting it. Also, side-effects of L-asparaginase treatment in acute lymphoblastic leukemia (ALL) have been discussed in the current review. L-asparaginase has been and is still one of the most widely studied therapeutic enzymes by researchers and scientists worldwide.