Rasburicase in the management of tumor lysis: an evidence-based review of its place in therapy

Orbital mass as the presenting symptom of diffuse large B-cell lymphoma causing spontaneous tumor lysis syndrome and rapid multisystem organ failure

A 68-year-old male presented with a one-month history of progressive proptosis and vision loss in the left eye. Examination of the left eye showed visual acuity of NLP, marked relative proptosis of 10 mm, and complete external ophthalmoplegia. CT orbits showed an extensive left orbital lesion with proptosis. Urgent orbital biopsy was undertaken. Intraoperatively, the patient developed new atrial flutter and fever. Bloodwork revealed metabolic derangements suggestive of tumor lysis syndrome. Systemic evaluation revealed a large tumor burden involving the retroperitoneal space. Histopathology of the orbital specimen showed non-germinal center diffuse large B-cell lymphoma. The patient passed away 3 days postoperatively due to rapidly progressive multisystem organ failure. Our case demonstrates an unusually aggressive presentation of DLBCL in which orbital mass was the first presentation of spontaneous tumor lysis syndrome owing to large systemic tumor burden.

Tumour lysis syndrome

Tumour lysis syndrome (TLS) represents a critical oncological emergency characterized by extensive tumour cell breakdown, leading to the swift release of intracellular contents into the systemic circulation, outpacing homeostatic mechanisms. This process results in hyperuricaemia (a by-product of intracellular DNA release), hyperkalaemia, hyperphosphataemia, hypocalcaemia and the accumulation of xanthine. These electrolyte and metabolic imbalances pose a significant risk of acute kidney injury, cardiac arrhythmias, seizures, multiorgan failure and, rarely, death. While TLS can occur spontaneously, it usually arises shortly after the initiation of effective treatment, particularly in patients with a large cancer cell mass (defined as ≥500 g or ≥300 g/m2 of body surface area in children). To prevent TLS, close monitoring and hydration to improve renal perfusion and urine output and to minimize uric acid or calcium phosphate precipitation in renal tubules are essential. Intervention is based on the risk of a patient of having TLS and can include rasburicase and allopurinol. Xanthine, typically enzymatically converted to uric acid, can accumulate when xanthine oxidases, such as allopurinol, are administered during TLS management. Whether measurement of xanthine is clinically useful to optimize the use of allopurinol or rasburicase remains to be determined.

A Study to Evaluate the Effectiveness and Safety of Prephase Steroid Treatment before Remission Induction Chemotherapy in Patients with Pediatric Acute Lymphoblastic Leukemia Using Common Data Model-Based Real-World Data: A Retrospective Observational Study

Background

Rapid reduction of leukemic cells in the bone marrow during remission induction chemotherapy (RIC) can lead to significant complications such as tumor lysis syndrome (TLS). We investigated whether prephase steroid treatment before RIC could decrease TLS incidence and improve overall survival in pediatric patients with acute lymphoblastic leukemia (ALL).

Methods

Data were extracted from the Common Data Model databases in two tertiary-care hospitals in Seoul, South Korea. Patients were classified into the treated or untreated group if they had received RIC with prephase steroid treatment ≥7 days before RIC in 2012-2021 or not, respectively. Stabilized Inverse Probability of Treatment Weighting (sIPTW) was applied to ensure compatibility between the treated and untreated groups. The incidence of TLS within 14 days of starting RIC, overall survival (OS), and the incidence of adverse events of special interest were the primary endpoints. Multiple sensitivity analyses were performed.

Results

Baseline characteristics were effectively balanced between the treated (n=308.4) and untreated (n=246.6) groups after sIPTW. Prephase steroid treatment was associated with a significant 88% reduction in the risk of TLS (OR 0.12, 95% CI: 0.03-0.41). OS was numerically greater in the treated group than in the untreated group although the difference was not statistically significant (HR 0.64, 95% CI 0.25-1.64). The treated group experienced significantly elevated risks for hyperbilirubinemia and hyperglycemia. The reduction in TLS risk by prephase steroid treatment was maintained in all of the sensitivity analyses.

Conclusion

Prephase steroid treatment for ≥7 days before RIC in pediatric patients with ALL reduces the risk of TLS, while careful monitoring for toxicities is necessary. If adequately analyzed, real-world data can provide crucial effectiveness and safety information for proper management of pediatric patients with ALL, for whom prospective randomized studies may be difficult to perform for ethical and practical reasons.

Rasburicase in treating tumor lysis syndrome: An umbrella review

Tumor lysis syndrome (TLS) remains a debilitating cause of hospitalization and death in patients with cancer and is a significant challenge for healthcare providers despite advancements in its management. This umbrella review analyzed the results of meta-analyses on the use of rasburicase in the treatment of patients with cancer. A literature search was performed of five databases (PubMed, Google Scholar, Cochrane Library, Scopus, Global Index Medicus, and ScienceDirect) for articles with full texts available online. A measurement tool to assess systematic reviews 2 (AMSTAR 2) was used to assess the quality of the included studies, and Review Manager software was used to conduct all statistical analyses. The systematic search identified eight relevant meta-analyses, with primary analyses including outcome data that analyzed mortality, renal failure, and comparisons with allopurinol. The pooled data showed that rasburicase effectively reduced TLS development and serum uric acid levels in children and adults with malignancies. Most outcomes did not differ significantly compared with those of allopurinol. Future trials should focus on the cost-effectiveness of rasburicase compared to that of allopurinol while including high-, intermediate-, and low-risk patients. Rasburicase is safe and effective for managing patients with TLS. However, recent large-scale meta-analyses have reported conflicting results. Most meta-analyses were graded as low to critically low as per AMSTAR 2. The analysis revealed that the benefit of rasburicase did not differ significantly from that of allopurinol, which has higher cost-effectiveness and fewer side effects.

Safety and Effectiveness of Rasburicase in the Control of Hyperuricemia in Pediatric Patients with Non-Hodgkin's Lymphoma and Acute Leukemia: An Open-Label, Single-Arm, Multi-center, Interventional Study

INTRODUCTION

Despite rasburicase's proven efficiency in Caucasians, Japanese, and Koreans, studies evaluating the safety and effectiveness of rasburicase in Chinese pediatric patients with non-Hodgkin's lymphoma (NHL) and acute leukemia (AL) in particular are lacking.

OBJECTIVE

The aim was to evaluate the safety and effectiveness of rasburicase in Chinese pediatric patients with NHL and AL.

METHODS

In this phase IV, open-label, non-randomized, single-arm, multi-center, interventional study (NCT04349306), children newly diagnosed with NHL or AL who received 0.20 mg/kg/day of rasburicase were included. The primary objective was to assess the safety of rasburicase by the incidence of adverse events (AEs). The secondary objective was to determine the effectiveness of rasburicase in the control of hyperuricemia.

RESULTS

Out of 50 patients, 25 reported a total of 76 treatment-emergent adverse events (TEAEs), including eight TEAEs of grade ≥ 3 in 12 patients. A drug-related serious AE was reported in one patient, and there was no incidence of death. The response rate in the intent-to-treat population was 100.0% (95% confidence interval 82.4-100.0) in patients (n = 19) with baseline uric acid level of > 8.0 mg/dL. Similarly, the response rate was 86.2% (n = 25) among 29 patients (60.4%) with baseline uric acid levels of ≤ 8.0 mg/dL. The maximum mean percentage decrease of plasma uric acid level in the overall patients was 96.9%.

CONCLUSION

Rasburicase was well tolerated and effective in controlling hyperuricemia in Chinese pediatric patients with NHL and AL.

Rasburicase-Induced Falsely Low Measurement of Uric Acid in Tumor Lysis Syndrome: A Report of Two Cases

Rasburicase, a recombinant urate-oxidase enzyme, can significantly catalyze the oxidation of uric acid to allantoin. It was approved by the US Food and Drug Administration (FDA) to control blood uric acid levels in both pediatric and adult patients especially those with tumor lysis syndrome. It is quite important to realize that rasburicase can continue to be effective ex vivo and cause falsely low results if the blood sample is not contained and transported in ice water immediately. We presented two cases of falsely low measurement of blood uric acid caused by rasburicase and elaborated the proper method for collecting and transporting blood samples from patients using rasburicase.

Acute Tumor Lysis Syndrome: A Metabolic Emergency in Cancer Patients

Tumor lysis syndrome (TLS) can be a life-threatening complication that occurs following the onset of chemotherapy treatment, most commonly in association with high-grade lymphoproliferative pathologies such as acute lymphoblastic leukemia and Burkitt lymphoma. The massive cell lysis caused by cytotoxic therapy leads to the rapid release in the blood of intracelullary products and the onset of severe metabolic and electrolytic complications (hyperkalemia, hyperphosphatemia, hypocalcemia and hyperuricemia) upto the acute renal failure. This article describes the incidence and pathophysiological basis of TLS, focusing on the new therapeutic strategies implemented over the last few years, especially with regard to the treatment of hyperuricemia. In particular, it highlights the characteristics of a recent drug, Rasburicase, as a safe and effective alternative, compared to traditional allopurinol therapy, for prophylaxis and treatment of children with hyperuricemia induced by chemotherapy.

Advanced Practice Perspectives on Preventing and Managing Tumor Lysis Syndrome and Neutropenia in Chronic Lymphocytic Leukemia

Tumor lysis syndrome (TLS) and neutropenia are significant toxicities in the treatment of chronic lymphocytic leukemia (CLL). Both TLS and neutropenia can lead to potentially life-threatening complications for patients with chronic lymphocytic leukemia undergoing antineoplastic therapy. This article focuses on diligent risk assessment, prophylaxis, early identification, monitoring, patient education, and prompt intervention for TLS and neutropenia. These are all necessary steps to reduce life-threatening complications. Guidelines are available for risk assessments for both TLS and neutropenia. Once risk is established, prophylaxis and monitoring recommendations can be found in available guidelines. There are no established guidelines or widely used decision-making standards for the treatment of clinical TLS. General management strategies are well documented in the literature, with some degree of customization to each individual patient. If fever occurs in the setting of neutropenia, there are well-established guidelines for management, including guidance on anti-infective agents and use of growth factors. In addition, awareness and proper actions regarding TLS and neutropenia are key to preventing treatment delays, dose reductions, or treatment discontinuation. Adequate planning for TLS and neutropenia is critical to optimize patient outcomes.

Computational Approach for Rational Design of Fusion Uricase with PAS Sequences

Tumor lysis syndrome is a life-threatening condition for humans due to the lack of urate oxidase. In this study, several variants of PASylated uricase from the Aspergillus flavus species were analyzed computationally to find the appropriate fusions to solve short half-life and stability concern. The Ab initio method was performed using Rosetta software to structurally characterize the PAS sequences. The 3D structures of fusions were predicted for fused C- or N-terminally PAS sequences in different length to the uricase. The refinement and energy minimization steps revealed that physicochemical and conformational properties of fusions improved while the structures possessed prolonged PAS sequences. Molecular docking results showed that the highest binding affinity to uric acid belonged to uricase-PAS1-100 by the formation of six hydrogen and four non-hydrogen bonds. Altogether, the results indicated that the PASylation process would be promising upon the production of urate oxidase with improved solubility and stability.

Rasburicase in hemolytic uremic syndrome related to Shiga toxin-producing Escherichia coli: a report of nine cases

BACKGROUND

Hyperuricemia might induce additional renal damage in children with hemolytic uremic syndrome related to Shiga toxin-producing Escherichia coli (STEC-HUS). A few case reports have shown rasburicase to be effective in decreasing serum uric acid (UA) and improving renal function. However, there is only one report on the use of rasburicase in a child with STEC-HUS, which shows satisfactory results. We describe here the safety and efficacy of rasburicase in nine additional cases.

CASE-DIAGNOSIS/TREATMENT

Data from 9 children (5 females, median age 2 years) who received rasburicase were reviewed. At admission, 6 were dehydrated and 3 euvolemic. Dehydrated patients received saline solution and afterwards, as well as for those initially euvolemic, we aimed to keep a neutral fluid balance. Despite this, urine output did not increase. Baseline creatinine was 3.35 mg/dL (1.47-9.1) and UA 11.4 mg/dL (8.3-19.2). A single dose of rasburicase (0.2 mg/kg) was given 6-8 h after admission, which reduced UA levels to 1.8 mg/dL (0.3-5, p = 0.009) on the next day. However, renal parameters worsen and dialysis had to be initiated. Then, while still on dialysis, a UA rebound occurred in all cases reaching a peak of 8.9 mg/dL (4.5-13.8). Just after a steady increase in urine output, a sustained decline in UA levels concomitantly occurred with an improvement in renal function. At discharge, all patients reached normal UA levels. No side effects were recorded.

CONCLUSIONS

Administration of rasburicase in children with STEC-HUS was safe but failed to provide any significant benefit despite fall in serum UA levels.

Evaluation of Rasburicase Use in the Fraser Health Authority: A Retrospective Review

BACKGROUND

Rasburicase, a recombinant urate oxidase, is restricted in the Fraser Health Authority (FHA) to the "treatment of acute or at high risk of tumour lysis syndrome [TLS], when other therapeutic options are not suitable". The manufacturer's recommended dosage is 0.2 mg/kg daily for up to 7 days. Given the high cost of this drug, several studies have investigated other strategies and found that a single dose, repeated as needed, is effective in reducing serum uric acid. However, there are currently no guidelines in FHA for the use of rasburicase, which may result in different prescribing practices within the health authority.

OBJECTIVES

To describe the prescribing of rasburicase in FHA, including indications and doses, and to report the uric acid-lowering effects of rasburicase and any clinical outcomes, such as dialysis or death.

METHODS

This retrospective descriptive chart review included adult patients receiving care in FHA for whom rasburicase was prescribed between June 1, 2010, and November 30, 2016. Descriptive statistics were used to summarize patient characteristics and results.

RESULTS

The prescribing practices for rasburicase in this health authority were largely inconsistent, but the most common dose administered was 3 mg (8/12 [67%] among those receiving rasburicase for prophylaxis and 9/32 [28%] among those receiving rasburicase for treatment; combined total 17/44 or 39%). Regardless of dose, rasburicase reduced serum uric acid levels to less than 476 μmol/L and decreased the risk of TLS.

CONCLUSIONS

Having a uniform approach-involving a single dose that can be repeated as needed-for prevention and treatment of elevated serum uric acid levels could result in sufficient reduction of uric acid levels with fewer doses and lower cost. The results of this study support the need for a resource in FHA to guide and standardize the use of rasburicase.

Allantoin reduces cell death induced by cisplatin: possible implications for tumor lysis syndrome management

Massive lysis of tumor mass in cancer patients under chemotherapy regimens generates high levels of uric acid, leading to what is known as tumor lysis syndrome (TLS). Rasburicase, a recombinant urate oxidase, converts urate to allantoin, which is readily excreted by the kidneys. Even though there is a high production of allantoin from urate in cancer patients following rasburicase treatment, there are no studies on how allantoin excess could interfere with chemotherapy. We have evaluated allantoin interference with cisplatin efficiency on the lung cancer cell line H460 in vitro. The cells were treated with cisplatin (33 µM), with or without allantoin, for 48 h, in the presence or absence of UV light, and N-acetyl-L-cysteine (NAC) for 24 h. Cell viability, cell cycle, ROS production, apoptosis and immunoblot assays were performed. We showed that allantoin reduced the apoptosis induced by cisplatin in the H460 cell line. However, the activity of carboplatin and oxaliplatin, betulinic acid, TIBA, UV and H₂O₂ was not affected by allantoin. NMR spectroscopy showed that allantoin reduces cisplatin activity through direct interaction with cisplatin.

Tumor Lysis Syndrome in Chronic Lymphocytic Leukemia with Novel Targeted Agents

Tumor lysis syndrome (TLS) is an uncommon but potentially life-threatening complication associated with the treatment of some cancers. If left untreated, TLS may result in acute renal failure, cardiac dysrhythmia, neurologic complications, seizures, or death. Tumor lysis syndrome is most commonly observed in patients with hematologic malignancies with a high proliferation rate undergoing treatment with very effective therapies. In chronic lymphocytic leukemia (CLL), historically, TLS has been observed less often, owing to a low proliferation rate and slow response to chemotherapy. New targeted therapies have recently been approved in the treatment of CLL, including the oral kinase inhibitors, idelalisib and ibrutinib, and the B-cell lymphoma-2 protein inhibitor, venetoclax. Several others are also under development, and combination strategies of these agents are being explored. This review examines the diagnosis, prevention, and management of TLS and summarizes the TLS experience in CLL clinical trials with newer targeted agents. Overall, the risk of TLS is small, but the consequences may be fatal; therefore, patients should be monitored carefully. Therapies capable of eliciting rapid response and combination regimens are increasingly being evaluated for treatment of CLL, which may pose a higher risk of TLS. For optimal management, patients at risk for TLS require prophylaxis and close monitoring with appropriate tests and appropriate management to correct laboratory abnormalities, which allows for safe and effective disease control.

IMPLICATIONS FOR PRACTICE

Tumor lysis syndrome (TLS) is a potentially fatal condition observed with hematologic malignancies, caused by release of cellular components in the bloodstream from rapidly dying tumor cells. The frequency and severity of TLS is partly dependent upon the biology of the disease and type of therapy administered. Novel targeted agents highly effective at inducing rapid cell death in chronic lymphocytic leukemia (CLL) may pose a risk for TLS in patients with tumors characterized by rapid growth, high tumor burden, and/or high sensitivity to treatment. In this review, prevention strategies and management of patients with CLL who develop TLS are described.

A Numerical Approach for Kinetic Analysis of the Nonexponential Thermoinactivation Process of Uricase

Prior to the exponential decrease of activity of a uricase from Candida sp. during storage at 37 °C, there was a plateau period of about 4 days at pH 7.4, 12 days at pH 9.2, and about 22 days in the presence of 30 μM oxonate at pH 7.4 or 9.2, but no degradation of polypeptides and no activity of resolved homodimers. To reveal determinants of the plateau period, a dissociation model involving a serial of conformation intermediates of homotetramer were proposed for kinetic analysis of the thermoinactivation process. In the dissociation model, the roles of interior noncovalent interactions essential for homotetramer integrity were reflected by an equivalent number of the artificial weakest noncovalent interaction; to avoid covariance among parameters, the rate constant for disrupting the artificial weakest noncovalent interaction was fixed at the minimum for physical significance of other parameters; among thermoinactivation curves simulated by numerical integration with different sets of parameters, the one for least-squares fitting to an experimental one gave the solution. Results found that the equivalent number of the artificial weakest noncovalent interaction primarily determined the plateau period; kinetics rather than thermodynamics for homotetramer dissociation determined the thermoinactivation process. These findings facilitated designing thermostable uricase mutants.

Acute kidney injury in critically ill cancer patients: an update

Patients with cancer represent a growing group among actual ICU admissions (up to 20 %). Due to their increased susceptibility to infectious and noninfectious complications related to the underlying cancer itself or its treatment, these patients frequently develop acute kidney injury (AKI). A wide variety of definitions for AKI are still used in the cancer literature, despite existing guidelines on definitions and staging of AKI. Alternative diagnostic investigations such as Cystatin C and urinary biomarkers are discussed briefly. This review summarizes the literature between 2010 and 2015 on epidemiology and prognosis of AKI in this population. Overall, the causes of AKI in the setting of malignancy are similar to those in other clinical settings, including preexisting chronic kidney disease. In addition, nephrotoxicity induced by the anticancer treatments including the more recently introduced targeted therapies is increasingly observed. However, data are sometimes difficult to interpret because they are often presented from the oncological rather than from the nephrological point of view. Because the development of the acute tumor lysis syndrome is one of the major causes of AKI in patients with a high tumor burden or a high cell turnover, the diagnosis, risk factors, and preventive measures of the syndrome will be discussed. Finally, we will briefly discuss renal replacement therapy modalities and the emergence of chronic kidney disease in the growing subgroup of critically ill post-AKI survivors.

Metastatic testicular cancer presenting with liver and kidney dysfunction treated with modified BEP chemotherapy combined with continuous hemodiafiltration and rasburicase

A 25-year-old man was admitted to our hospital complaining of right scrotal pain and upper abdominal pain. A computed tomographic scan indicated a right scrotal mass, a huge liver mass, and multiple lung masses, although there was no enlarged retroperitoneal lymph node swelling. Laboratory tests showed severe liver and kidney dysfunction and high levels of serum α-fetoprotein (11 997 ng/ml). Although needle biopsies of the testicular and liver masses were performed, the tissues were insufficient for a pathological diagnosis. As liver and kidney function worsened, we started chemotherapy with bleomycin, etoposide, and cisplatin (BEP chemotherapy), which was modified because of the liver and renal dysfunction. We also used continuous hemodiafiltration and rasburicase to prevent tumor lysis syndrome. After induction of chemotherapy, the liver and kidney dysfunction improved immediately and the high orchiectomy was performed on day 8 after chemotherapy. The pathological diagnosis was a yolk sac tumor. He underwent four courses of the BEP regimen and five courses of the TIN regimen (paclitaxel, ifosphamide, and nedaplatin), followed by the resection of liver metastases. There was no evidence of viable cells in the resected liver and no recurrence was evident at 1 year postoperatively.

Spontaneous Tumor Lysis Syndrome: A Case Report and Critical Evaluation of Current Diagnostic Criteria and Optimal Treatment Regimens

Tumor lysis syndrome (TLS) is a known complication of malignancy and its treatment. The incidence varies on malignancy type, but is most common with hematologic neoplasms during cytotoxic treatment. Spontaneous TLS is thought to be rare. This case study is of a 62-year-old female admitted with multisystem organ failure, with subsequent diagnosis of aggressive B cell lymphoma. On admission, laboratory abnormalities included renal failure, elevated uric acid (20.7 mg/dL), and 3+ amorphous urates on urinalysis. Oliguric renal failure persisted despite aggressive hydration and diuretic use, requiring initiation of hemodialysis prior to chemotherapy. Antihyperuricemic therapy and hemodialysis were used to resolve hyperuricemia. However, due to multisystem organ dysfunction syndrome with extremely poor prognosis, the patient ultimately expired in the setting of a terminal ventilator wean. Although our patient did not meet current TLS criteria, she required hemodialysis due to uric acid nephropathy, a complication of TLS. This poses the clinical question of whether adequate diagnostic criteria exist for spontaneous TLS and if the lack of currently accepted guidelines has resulted in the underestimation of its incidence. Allopurinol and rasburicase are commonly used for prevention and treatment of TLS. Although both drugs decrease uric acid levels, allopurinol mechanistically prevents formation of the substrate rasburicase acts to solubilize. These drugs were administered together in our patient, although no established guidelines recommend combined use. This raises the clinical question of whether combined therapy is truly beneficial or, conversely, detrimental to patient outcomes.