Severe methotrexate toxicity precipitated by intravenous radiographic contrast

Methotrexate (MTX), a widely used anticancer agent, and intravenous iodinated contrast used for radiographic studies can both cause acute renal failure. Their combined exposure may place patients at higher risk for renal failure. This report describes 2 pediatric patients with MTX toxicity precipitated by the use of intravenous radiographic contrast. One patient recovered with leucovorin rescue therapy, whereas the second patient responded to carboxypeptidase-G2. Both patients suffered MTX-related toxicities including myelosuppression and mucositis, but recovered full renal function and tolerated further high-dose MTX therapy. These cases suggest that intravenous iodinated contrast should be avoided in patients receiving high-dose MTX.     

The effect of methotrexate pharmacokinetics and of leucovorin rescue on the prognosis of osteosarcoma

A total of 129 high-dosage methotrexate therapies performed in 19 patients with osteosarcoma were retrospectively analyzed. Serum methotrexate peak concentrations were found to vary widely, both inter-individually as well as in the same patient. The measured MTX peak concentrations correlated closely with pharmacokinetic data such as area under the curve and total body clearance. No correlations were found between the serum MTX correlations and different times after methotrexate administration. Increase in leucovorin rescue or low MTX peak concentrations were associated with poor prognosis. High-dosage methotrexate therapies with leucovorin rescue need to be further optimized in accordance with biochemical knowledge of the mode of action and the individual pharmacokinetic data of methotrexate. Such optimization may be expected to improve the prognosis for osteosarcoma. Serum methotrexate concentrations should be determined not only 24, 48, and 72 hours after methotrexate administration, in order to avoid elevated toxicity of the therapy, but also at the start of methotrexate infusion, in order to influence MTX peak concentrations at an early stage if necessary. Measurement of L-leucovorin in serum will be necessary, to enable a restrictive leucovorin rescue to be performed safely.     

Sequential chemotherapy of advanced colorectal cancer with standard or high-dose methotrexate followed by 5-fluorouracil

Thirty patients with advanced measurable colorectal cancer were randomized to receive either methotrexate (MTX) 200 mg/m² or 40 mg/m², followed in four hours by 5-fluorouracil (5-FU) 600 mg/m². Patients receiving the higher dose MTX were given leucovorin rescue 24 hours later. Eight of 13 patients treated with 200 mg/m² MTX + 5-FU developed severe hematologic toxicity, leading to two toxic deaths. In addition, 9/13 developed mild azotemia, and three patients had severe gastrointestinal toxicity. No patients with prior chemotherapy responded to either regimen. Among those without prior chemotherapy, there were two of six and three of eight partial responses, respectively, in the 200 mg/m² and 40 mg/m² MTX regimens. Sequential 200 mg/m² MTX followed by 5-FU after four hours has unacceptable toxicity. Sequential treatment with standard dose MTX + 5-FU is tolerable and merits further study.     

Clinical pharmacology of methotrexate

Methotrexate (MTX), a potent folate antagonist by virtue of its ability to inhibit the enzyme dihydrofolate reductase [1], continues to be a useful cancer chemotherapeutic agent [2]. Information not only on its mechanism of action, but also its pharmacology has led to improved dosage schedules of this drug alone and in combination. The use of high (gm) doses of MTX followed by leucovorin “rescue” has required close attention to the blood levels of this drug and has stimulated further studies of its clinical pharmacology, especially of high-dose regimens. This review summarizes the present status of the clinical pharmacology of MTX.     

Erythrocyte concentrations of metabolites or cumulative doses of 6-mercaptopurine and methotrexate do not predict liver changes in children treated for acute lymphoblastic leukemia

BACKGROUND: During therapy consisting of 6MP and MTX, metabolites accumulate in the erythrocytes. The erythrocyte levels of metabolites reflect the intensity of therapy. Whether they are associated with hepatotoxicity manifested as histological liver changes is not known. We studied the association of the metabolites and cumulative doses of 6MP and MTX with histological liver disease. METHODS: Serial measurements of E-TGN, E-MTX, and ALT during maintenance therapy were performed and cumulative doses of 6MP and MTX were calculated as g/m2 in 16 children with ALL. Each subject underwent a percutaneous liver biopsy at the end of therapy to screen for histological liver disease. RESULTS: No differences in E-TGN, E-MTX, or cumulative doses of 6MP or MTX were detected in the children with ALL with liver fibrosis compared to those without fibrosis, or in the children with less liver fatty change compared to those with more fatty change. Serum median ALT levels correlated significantly positively with cumulative doses of 6MP during therapy (rS = 0.527, P = 0.036), but not with cumulative doses of MTX, or E-TGN, or E-MTX. CONCLUSIONS: Erythrocyte levels of the metabolites or the cumulative doses of 6MP and MTX do not predict histological liver disease in children treated for ALL.     

Safety of delayed leucovorin “rescue” following high-dose methotrexate in children

High-dose methotrexate (HDMTX) with leucovorin (CF) “rescue” is being investigated for treatment of many malignant tumors. CF is usually begun 2 hours after ending the HDMTX infusion. However, since CF and methotrexate compete for the same cellular transport system, at high extracellular methotrexate concentrations it may be impossible to “rescue” cells with CF. A regimen of HDMTX with delayed leucovorin “rescue” was therefore designed. In this program, a 6-hour infusion of methotrexate (7.5 gm/m²) was followed 24 hours later by leucovorin “rescue.” Nine patients with osteogenic sarcoma received 115 courses of this treatment. Toxicity was minimal. Plasma methotrexate values were identical to those following early CF “rescue” regimens. HDMTX with delayed “rescue” is well tolerated. Although theoretically sound, further studies are needed to determine its efficacy in comparison to standard early “rescue” regimens.     

How long can folinic acid rescue be delayed after high‐dose methotrexate without toxicity?

To determine the optimal time of folinic acid rescue after methotrexate (MTX) treatment in patients with ALL, we selected and evaluated relevant studies that included doses, rescue delay, and side effects. Rescue at 42–48 hours resulted in considerable toxicity, except when low doses of MTX were used (1 g/m²) or serum MTX levels remained consistently low at 24, 30, and 36 hours. Rescue started at 30–36 hours was safe. In the absence of evidence that later rescue improves prognosis, we suggest that folinic acid rescue (105 mg/m²) be started no later than 36 hours from the start of MTX (5–6 g/m²). Pediatr Blood Cancer 2014;61:7–10. © 2013 Wiley Periodicals, Inc.     

Randomized comparison of moderate-dose methotrexate infusions to oral methotrexate in children with intermediate risk acute lymphoblastic leukemia: A Childrens Cancer Group study

Methotrexate (MTX) infusions of 500–1,000 mg/m² over 24 hours may improve survival and prevent relapse in children with acute lymphoblastic leukemia (ALL). Childrens Cancer Group (CCG) Study 139 compared weekly oral methotrexate 20 mg/m²/week (oral MTX) to MTX 500 mg/m² infused over 24 hours (IV MTX) three times during consolidation and every 6 weeks during maintenance in 164 children with intermediate-risk ALL, i.e., those patients over age 1 year with white blood cell count 10,000 to 49,999/ml and no bulky extramedullary disease. Median follow-up for CCG-139 exceeded 75 months. Thirty-four events occurred among 80 patients receiving IV and oral MTX and 36 events among 84 patients receiving oral MTX. Two children died during induction and one did not enter remission. Remission induction rate is 98%. There have been 26 marrow relapses, 11 combined marrow and extramedullary relapses, 24 CNS relapses, and five testicular or other relapses. The frequency and distribution of relapses does not differ between the two regimens. For the entire group, overall event-free survival (EFS) at 6 years is 57.9% (standard deviation = 4.0%) and actuarial survival is 80.0% (standard deviation = 3.3%). Of the 29 patients with isolated extramedullary relapse, 18 survive free of a second event, a median of 42 months from relapse. In contrast to other trials, this trial does not show that IV MTX in this dose and schedule offers an advantage over standard therapy for this group of children. © 1996 Wiley-Liss, Inc.     

New aspects of the determination of blood methotrexate levels in leukemic children

Serum and CSF concentrations after medium dosage of methotrexate (MTX; 500 mg/m2 - 1,000 mg/m2) have been determined by an enzymatic assay during 142 infusions in children with ALL. If the dose of MTX was 500 mg/m2 MTX concentrations in CSF were under 10(-6) M/l in 40% of the treatments but only in 22%, when the dose was increased to 1,000 mg/m2. The systemic clearance of MTX was found to be increased significantly by the 2nd MTX treatment in children who relapsed thereafter. Such a phenomenon was not observed in children who continued in remission. The relapse free survival of children, whose MTX-clearance remained constant by the 2nd MTX treatment was significantly longer. No serious MTX toxicity has been observed in our patients.     

Pharmacokinetics and toxicity of methotrexate in children with Down syndrome and acute lymphocytic leukemia

Children with Down syndrome and acute lymphocytic leukemia (ALL) have poor tolerance to antineoplastic drugs, including methotrexate (MTX). We evaluated MTX pharmacokinetics and toxicity in five patients with Down syndrome and ALL who had received multiple high doses of MTX (1 g/m2). Three control patients without Down syndrome were matched to each case according to sex, race, age, and initial leukocyte count. Median MTX plasma concentrations, measured 42 hours after infusion, were significantly higher in patients with Down syndrome versus control patients (average 0.47 vs 0.24 mumol/L, respectively, P = 0.03). When a 42-hour MTX concentration of 0.5 mumol/L was used to identify patients at risk for toxicity, more courses were considered at high risk for toxicity among patients with Down syndrome (31 of 62, 50%) than in control patients (13 of 214, 6.1%, P less than 0.0001). The average MTX clearance was 64.1 mL/min/m2 in Down syndrome vs an average control value of 80.6 mL/min/m2 (P = 0.13). Toxicity after each high-dose MTX course was graded according to standardized criteria. Grades 2 through 4 gastrointestinal toxicity and grades 3 and 4 hematologic toxicity occurred more frequently in the patients with Down syndrome (36% and 13.4% of courses, respectively) vs the control patients (3.6% and 0.9% respectively, P less than 0.0001 for both). This higher frequency of toxicity occurred despite higher doses and prolonged duration of leucovorin given to all patients with Down syndrome. We conclude that altered MTX pharmacokinetics may contribute to the higher incidence of MTX-induced toxicity seen in patients with Down syndrome.     

Serum Creatinine Versus Plasma Methotrexate Levels to Predict Toxicities in Children Receiving High-dose Methotrexate

Facilities for measuring methotrexate (MTX) levels are not available everywhere, potentially limiting administration of high-dose methotrexate (HDMTX). We hypothesized that serum creatinine alteration after HDMTX administration predicts MTX clearance. Overall, 122 cycles in 50 patients of non-Hodgkin lymphoma or acute lymphoblastic leukemia aged ≤18 years receiving HDMTX were enrolled prospectively. Plasma MTX levels were measured at 12, 24, 36, 48, 60, and 72 hours; serum creatinine was measured at baseline, 24, 48, and 72 hours. Correlation of plasma MTX levels with creatinine levels and changes in creatinine from baseline (Δ creatinine) were evaluated. Plasma MTX levels at 72 hours showed positive correlation with serum creatinine at 48 hours (P = .011) and 72 hours (P = .013) as also Δ creatinine at 48 hours (P = .042) and 72 hours (P = .045). However, cut-off value of either creatinine or Δ creatinine could not be established to reliably predict delayed MTX clearance. Greater than 50% Δ creatinine at 48 and 72 hours significantly predicted grade 3/4 leucopenia (P = .036 and P = .001, respectively) and thrombocytopenia (P = .012 and P = .009, respectively) but not mucositis (P = .827 and P = .910, respectively). Delayed MTX elimination did not predict any grade 3/4 toxicity. In spite of demonstration of significant correlation between serum creatinine and Δ creatinine with plasma MTX levels at 72 hours, cut-off value of either variable to predict MTX delay could not be established. Thus, either of these cannot be used as a surrogate for plasma MTX estimation. Interestingly, Δ creatinine effectively predicted hematological toxicities, which were not predicted by delayed MTX clearance.     

Association of ABCC2 with levels and toxicity of methotrexate in Malaysian Childhood Acute Lymphoblastic Leukemia (ALL)

Abstract

Studies had shown that genetic polymorphism plays a significant role in the pharmacokinetics and pharmacodynamics variation of high dose methotrexate (MTX), 5000?mg/m² regimen. The objective of this study was to investigate the genetic variations associated with the serum level and toxicity of MTX in Malaysian children with acute lymphoblastic leukemia (ALL). Thirty-eight patients were genotyped for rs717620 (ABCC2), rs4948496 (ARID5B), rs1801133 (MTHFR) and rs4149056 (SLCO1B1). Serum levels of MTX at 48?h post 24?h of intravenous infusion were analyzed by high-performance liquid chromatography-mass spectrometry. The ABCC2 genotype was significantly associated with the serum levels of MTX at 48?h after treatment (p?=?0.017). Patients with CT and TT of rs717620 (ABCC2) and TC and CC of rs4948496 (ARID5B) were significantly associated with leukopenia grade I–IV (Fisher Exact Test; p?=?0.03 and 0.02, respectively). The three most common MTX related toxicities were leukopenia (60.5%), increased alanine aminotransferase enzyme (47.4%), and thrombocytopenia (47.4%). Our results demonstrate that by prescreening of patients for ABCC2 and ARID5B associated with the serum levels and adverse effects of MTX would identify patients at risk and therefore help a pediatric oncologist to personalize chemotherapy drugs for precision health.     

Risk factors associated with delayed methotrexate clearance and increased toxicity in pediatric patients with osteosarcoma

High‐dose methotrexate (HD‐MTX; 12 g/m²) is part of standard therapy for pediatric osteosarcoma (OS). Risk factors associated with MTX toxicity in children with OS are not well defined. We investigated the association between peak MTX levels (four‐hour) and delayed MTX clearance or treatment toxicity. Information was retrieved from electronic medical records of 33 OS patients treated with HD‐MTX at Texas Children's Hospital from 2008 to 2015. We found that the four‐hour MTX level did not contribute to toxicity or delayed MTX clearance. We demonstrated that certain demographic characteristics are associated with delayed clearance and increased toxicity.     

大剂量甲氨蝶呤治疗急性淋巴细胞白血病

目的研究3g/m2和5g/m2甲氨蝶呤(MTX)治疗急性淋巴细胞白血病(ALL)的血、脑脊液MTX浓度和不良反应。方法ALL患儿43例共接受98例次MTX3g/(m2·次)或5g/(m2·次)治疗,对两剂量组进行MTX血药质量浓度、脑脊液浓度及不良反应比较。结果1.MTX44、66h血药质量浓度与23hMTX血药质量浓度明显相关(P<0.05);2.不同个体间及同一个体不同时间使用同一给药方案血药质量浓度、脑脊液浓度水平差异较大;3.两剂量组不良反应发生率无明显差异(P>0.05),骨髓抑制、肝功能损害的MTX血药质量浓度无明显差异(P>0.05)。结论对于标危、高危ALL分别采用3、5g/(m2·次)的剂量是合理的,无严重不良反应发生。     

高剂量甲氨蝶呤排泄延迟解救措施的病例系列报告

背景：目前国内外对高剂量甲氨蝶呤（MTX）排泄延迟是否应该使用血液透析解救还存在争议。 目的：研究高通量血液透析（HF-HD）对肿瘤患儿MTX清除的有效性。 设计：病例系列报告。 方法：纳入2016年1月至2021年6月在上海交通大学医学院附属上海儿童医学中心血液肿瘤科行MTX化疗后44 h血药浓度＞10 μmol·L-1的连续病例,其中仅使用亚叶酸钙（CF）解救的患儿为非HF-HD组,使用HF-HD+CF解救的患儿为HF-HD组。比较2组患儿的胃肠道、肝功能、肾功能和血液系统毒性等指标。 主要结局指标：肝、肾功能不良反应发生率。 结果：20例发生20例次MTX延迟排泄,非HF-HD组9例,HF-HD组11例,两组患儿美国卫生及公共服务部常见不良事件评价标准v 4.0项目比较,CF组和HF-HD组肌酐、尿酸、ALT、AST、黏膜炎、24 h MTX浓度、MTX浓度恢复正常所需的时间差异均无统计学意义,两组患儿血液系统不良反应发生率差异无统计学意义（P＞0.05）;AST、ALT、发热、黏膜炎、WBC、NE、Hb、PLT异常发生率两组差异无统计学意义。 结论：肾功能正常的肿瘤患儿通过CF解救可有效安全清除MTX,非必要不选择透析。     

Methotrexate‐associated alterations of the folate and methyl‐transfer pathway in the CSF of ALL patients with and without symptoms of neurotoxicity

Background

Severe neurotoxicity has been observed after systemic high‐dose and intrathecal methotrexate (MTX) treatment. The role of biochemical MTX‐induced alterations of the folate and methyl‐transfer pathway in the development of neurotoxic symptoms is not yet fully elucidated.

Procedure

MTX, 5‐methyltetrahydrofolate, calcium folinate, S‐adenosylmethionine, and S‐adenosylhomocysteine were measured in the cerebrospinal fluid (CSF) of 29 patients with acute lymphoblastic leukemia (ALL) who were treated with high‐dose MTX (5 g/m²) followed by calcium folinate rescue (3 × 15 mg/m²) and/or intrathecal (8–12 mg) MTX. Two patients developed subacute MTX‐associated neurotoxicity. CSF was obtained by lumbal puncture 1–3 weeks after administration of MTX and shortly after the occurrence of neurotoxicity. The analytes were measured using HPLC assays with UV and/or fluorescence detection.

Results

In non‐toxic patients, CSF concentrations of 5‐methyltetrahydrofolate and S‐adenosylmethionine were in the normal range 2 weeks after administration of high‐dose and intrathecal MTX followed by rescue. In contrast, when these patients received intrathecal MTX without rescue, 5‐methyltetrahydrofolate concentrations were significantly decreased 12 days after the first MTX administration. S‐adenosylmethionine concentrations were significantly decreased up to 45 days. The two patients suffering from neurotoxicity had decreased levels of 5‐methyltetrahydrofolate and S‐adenosylmethionine during or following toxicity. S‐adenosylhomocysteine was determined in all samples of neurotoxic patients but was below the limit of quantification in most samples of non‐toxic patients. Calcium folinate was not detected; MTX was present only in samples obtained during its infusion.

Conclusion

Intrathecal MTX without folinate rescue as well as MTX‐associated neurotoxicity are likely to be associated with specific alterations of the folate and methyl‐transfer pathway. Pediatr Blood Cancer 2009;52:26–32. © 2008 Wiley‐Liss, Inc.     

Clinical significance of non-renal elimination mechanisms of methotrexate (MTX)

Biliary MTX levels in one patient undergoing intermediate dose MTX therapy (500 mg/m2) were measured by HPLC. At the end of the 24 h infusion period they were found in the range of the corresponding serum levels. In one other patients undergoing high-dose MTX therapy (12 g/m2) MTX serum levels in the slow elimination phase were lowered by orally applicated cholestyramine. In one further patient who developed renal failure under high-dose MTX therapy total body clearance of MTX could be markedly improved by cholestyramine per os. The data presented, suggesting an appreciable biliary secretion of the drug in man, are discussed in view of the current concepts of enterohepatic circulation of MTX.     

Theophylline for renal function in term neonates with perinatal asphyxia: a randomized, placebo-controlled trial

OBJECTIVE: To study whether prophylactic theophylline can reduce the incidence and/or severity of renal failure in term infants with perinatal asphyxia. STUDY DESIGN: Term neonates with severe perinatal asphyxia were randomized to receive a single dose of either theophylline (study group, n = 40) or placebo (control group, n = 30) during the first hour of life. Daily weight, output/input ratio, 24-hour fluid intake, and urine volumes were recorded during the first 5 days of life. Those infants with asphyxial renal failure were followed up for 1 year. RESULTS: The incidence of severe renal dysfunction was increased in the control group. Creatinine clearance was higher and excretion of beta 2 microglobulin (beta2M) was lower in the theophylline group. Conversely, the glomerular filtration rate was lower in the control group. In infants with renal failure, serum creatinine and creatinine clearance returned to normal in the neonatal period, and the increased beta2M excretion normalized by age 6 weeks. CONCLUSIONS: A single dose of theophylline within the first hour of birth in term neonates with perinatal asphyxia results in a significant decrease in serum creatinine level and urinary excretion of beta2M, along with an increase in creatinine clearance.     

Experiences with modified BFM protocols in the treatment of children with acute lymphoblastic leukemia (ALL) in East Germany 1981-1991]

Between September and August 1991 818 previously untreated children and adolescents up to 18 years of age with acute lymphoblastic leukemia were entered into two modified BFM-protocols. Patients with B-ALL were excluded. From 1981 to 1987 524 patients were entered into the randomized multicenter study ALL VII/81 (modified ALL-BFM 81 protocol). Patients were divided into three risk groups standard (SR), medium (MR), high risk (HR) using the BFM risk factor. In a connecting study from 1988 to 1991 294 patients were registered on the stratified and randomized multicentric trial ALL VIII/87 (modified ALL-BFM 86 study). The main modification in study ALL VII/81 concerned the duration of treatment. Patients were randomized into two groups. The first group received as a late reinduction protocol III and then therapy was stopped. The second group received 6-MP and MTX for another six months. The other whole treatment strategy of ALL-BFM 81 was adopted. In protocol ALL VIII/87 the only modification was the reduction of the MTX dosage from 5 g/m2 to 1 g/m2 with an infusion time of 24 hours (leucovorin rescue 15 mg/m2 after 48 and 54 hours). The probability of the event-free-survival (EFS) for study ALL VII/81 was 59%. CNS events were significantly more frequent in standard risk patients with intermediate dose MTX (4 x 0.5 g/m2) compared with the irradiation group (18 Gy). The EFS for SR patients amounts to 61%, for MR patients to 59% and for HR patients to 36%. There was no significant difference of EFS for the two groups with different duration of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Leucovorin and maximum tolerated dose toxicity of methotrexate in rats

High-dose methotrexate (HD-MTX) is widely used in combination chemotherapy and can be handled without life-threatening toxicity in combination with leucovorin (LV) rescue. However, in an experimental animal modelfortesting of short-term HD-MTX effects in anesthetized rats, the authors previously demonstrated intolerable toxicity and death within a few hours in some animals. Serum levels were below levels routinely found in patients on HD-MTX treatment. This study was aimed at disclosure of possible mechanisms for acute toxicity of MTX in rats. The previously determined maximum tolerated dose of 5 g/kg MTX was used as the test dose. The animals that died showed sudden reduction in heart rate and blood pressure. LV, 1 g/kg infused immediately prior to MTX, changed MTX elimination kinetics, but did not change the acute toxicity. The data of this study together with additional evidence obtained in the experimental model, suggest that MTX acute toxicity may not be related to its antiproliferative effect, but rather to perturbation of endothelial cell and platelet function.