Systematic review: genetic polymorphisms in the pharmacokinetics of high-dose methotrexate in pediatric acute lymphoblastic leukemia patients.

Variations in pharmacokinetic responses to high-dose methotrexate are essential for the prognosis and management of toxicity in the treatment of pediatric acute lymphoblastic leukemia (ALL) patients. This systematic review aimed to identify and evaluate genetic polymorphisms that are significantly associated with the pharmacokinetic parameters of methotrexate during the consolidation phase of pediatric ALL treatment. Using the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines, we systematically reviewed the literature from 2013 to 2023. The databases used were PubMed and Scopus. The outcomes of interest are the study design, patient characteristics, sample size, chemotherapy protocol utilized, pharmacokinetic parameters identified, and genetic polymorphisms implicated. We included 31 articles in the qualitative synthesis and found that the SLCO1B1, ABCB1, ABCC2, and MTHFR genes appear to play significant roles in MTX metabolism and clearance. Among these, variations in SLCO1B1 have the most significant and consistent impact on methotrexate clearance. These implicated variants may contribute to the precision and tailoring of HD-MTX treatment in pediatric ALL patients.

Untargeted metabolic profiling of high-dose methotrexate toxicity shows alteration in betaine metabolism.

Cardiotoxicity is a well-established adverse effect of several drugs across multiple therapeutic indications. It is particularly prevalent following anticancer therapy. In order to evaluate the changes in cellular metabolism associated with methotrexate cardiotoxicity, we treated Wistar rats with a single high dose of methotrexate (HDMTX), and after five days, the animals were sacrificed. We then analyzed the cardiotoxicity parameters in serum like Cardiac enzymes(CK-MB, Troponin T, ALP), Inflammatory markers (TNF-α and IL-6), oxidative stress markers (NO, NOX-2), histopathology and cardiac tissue with the goal of identifying a metabolic signature of cardiotoxicity using discovery-based metabolomics. The biochemical parameters for cardiac enzymes, oxidative stress and inflammatory markers showed a significant increase in all three categories in rats treated with HDMTX. These findings were mirrored in the histopathological analysis confirming cardiotoxicity due to HDMTX. The results showed a total of 95 metabolites that were found to be significantly (p < 0.05) modulated: either up- or downregulated in the HDMTX-treated group when compared with the control group. Using integrated pathway analysis we found these metabolites were associated with many important cardiac tissue metabolic pathways, such as the malate aspartate shuttle, taurine and hypotaurine metabolism, betaine metabolism, spermidine biosynthesis, and homocysteine degradation. Among them, L-arginine, homocysteine, and betaine were significantly upregulated, suggesting their possible association with cardiac tissue injury. Overall, we provided evidence for using untargeted metabolomics to identify novel metabolites associated with HDMTX cardiac toxicity.

Clinical characteristics and prognosis of patients with newly diagnosed primary central nervous system lymphoma: a multicentre retrospective analysis.

Bruton's tyrosine kinase inhibitors (BTKi) exhibit superior efficacy in relapsed/refractory primary central nervous system lymphoma (PCNSL), but few studies have evaluated patients with newly diagnosed PCNSL, and even fewer studies have evaluated differences in efficacy between treatment with BTKi and traditional chemotherapy. This study retrospectively analyzed the clinical characteristics of 86 patients with PCNSL and identified predictors of poor prognosis for overall survival (OS). After excluding patients who only received palliative care, 82 patients were evaluated for efficacy and survival. According to the induction regimen, patients were divided into the traditional chemotherapy, BTKi combination therapy, and radiotherapy groups; the objective response rates (ORR) of the three groups were 71.4%, 96.2%, and 71.4% (P = 0.037), respectively. Both median progression-free survival and median duration of remission showed statistically significant differences (P = 0.019 and P = 0.030, respectively). The median OS of the BTKi-containing therapy group was also longer than that of the traditional chemotherapy group (not reached versus 47.8 (32.5-63.1) months, P = 0.038).Seventy-one patients who achieved an ORR were further analyzed, and achieved an ORR after four cycles of treatment and maintenance therapy had prolonged OS (P = 0.003 and P = 0.043, respectively). In conclusion, survival, and prognosis of patients with newly diagnosed PCNSL are influenced by the treatment regimen, with the BTKi-containing regimen showing great potential.

Involvement of the ABCB1 C3435T Variant but Not the MTHFR C677T or MTHFR A1298C Variant in High-Dose Methotrexate-Induced Toxicity in Pediatric Acute Lymphoblastic Leukemia Patients in China.

Purpose: It remains unclear whether the MTHFR C677T, MTHFR A1298C and ABCB1 C3435T genetic variants are associated with methotrexate (MTX) elimination delay and high-dose MTX (HD-MTX) toxicities in the treatment of pediatric acute lymphoblastic leukemia (ALL). The aim of our study was to analyze the potential predictive role of MTHFR C677T, MTHFR A1298C and ABCB1 C3435T in toxicities and the relationship between these variants and MTX elimination delay during HD-MTX therapy in pediatric ALL patients. Patients and Methods: We conducted a retrospective study on ALL patients receiving HD-MTX treatment with available MTHFR C677T, MTHFR A1298C and ABCB1 C3435T genotype and 44-h plasma MTX levels. Logistic regression analyses and chi-square tests were used to assess the relationship between the variants and HD-MTX toxicities and MTX elimination delay. Results: Genotype frequencies were in Hardy-Weinberg equilibrium. MTX elimination delay did not significantly differ between MTHFR C677T and MTHFR A1298C or ABCB1 C3435T. Leukopenia (P=0.028), neutropenia (P=0.034) and oral mucositis (P=0.023) were 6.444-fold, 4.978-fold and 9.643-fold increased, respectively, in ABCB1 C3435T homozygous genotype (TT) patients compared to wild-type (CC) patients. No significant association was found between the toxicities investigated and MTHFR C677T or MTHFR A1298C. Conclusion: This study showed that the ABCB1 C3435T homozygous allele genotype (TT) is associated with increased MTX-related toxicities (leukopenia, neutropenia and oral mucositis). These results may help to distinguish pediatric ALL patients with a relatively high risk of MTX-related toxicities before HD-MTX infusion and optimize MTX treatment.

Primary Central Nervous System Lymphoma, Treatment Outcomes - 10 Year Experience. Single Center Study.

Background: Primary central nervous system lymphoma(PCNSL) is an aggressive, rare form of Non-Hodgkin lymphoma, characterized by the absence of systemic disease. There are limited data and no strictly defined guidelines for management of PCNSL. Objective: The aim of this study was to report a 10 year experience of PCNSL treatment, to evaluate treatment outcomes and asses Progression Free and Overall Survival of these patients. Methods: Study was conducted on the Haematology Clinic, Clinical center University of Sarajevo, BH, in the period from January 2012.-December 2022. Total sample of 24 patients were enrolled. All have undergone diagnostic surgery. Patients were treated with regimens based on High dose Methotrexate, with/without whole brain radiotherapy as consolidation. Treatment response was captured by imaging techniques. Patients who have relapsed were evaluated with imaging techniques and treated according to Methotrexate-based treatment protocols. Results: We have captured equal gender distribution. The median age of patients was 59.5 years (range 20-79). Pathohistological analysis confirmed DLBCL diagnosis in 22 patients, T cell lymphoma and anaplastic large cell lymphoma, each in 1 patient. Chemotherapy, chemotherapy combined with WBRT and radiotherapy were given to 5, 18 and 1 patients, respectively. The overall complete response rate (CR) was 87,15%. Those receiving combined modality-treatment had higher CR than those receiving chemotherapy (94,4% versus 60%). Out of 24 patients, 11 of them relapsed. The median time to relapse was 29 months (from 1 to 105). After second line of the treatment, CR was 54,5%, while 45,45% of patients died during the treatment. 4 patients relapsed for the second time with median time to relapse of 9 months (from 2 to 77). 2 year OS rate was 67%, and the median OS rate was 45,9 months. 2 year PFS rate was 31%. Conclusion: The OS and PFS rates indicate the usage of new drugs and consolidation with autologous stem cell transplantation in patients with PCNSL in order to achieve better treatment outcomes.

High-dose methotrexate and zanubrutinib combination therapy for primary central nervous system lymphoma.

In this editorial I comment on the article, published in the current issue of the World Journal of Clinical Oncology. Primary central nervous system lymphoma (PCNSL) is a disease of elderly and immunocompromised patients. The authors reported clinical results of 19 patients with PCNSL treated with zanubrutinib/high dose methotrexate (HD-MTX) until disease progression. They demonstrated that the combination of zanubrutinib with HD-MTX led to a marked clinical response and tolerability among these patients. They also observed that cerebrospinal fluid liquid biopsy to detect circulating tumor DNA may be a good option for evaluating treatment response and tumor burden in patients with PCNSL. PCNSL is a challenging disease for treatment as these patients present with different neurological states and comorbidities. Treatment has evolved over the years from whole brain radiotherapy to HD-MTX followed by autologous stem cell transplant. Gradually, treatment of patients with PCNSL is going to become individualized.

Risk factors associated with high-dose methotrexate induced toxicities.

INTRODUCTION: High-dose methotrexate (HDMTX) therapy poses challenges in various neoplasms due to individualized pharmacokinetics and associated adverse effects. Our purpose is to identify early risk factors associated with HDMTX-induced toxicities, paving the way for personalized treatment. AREAS COVERED: A systematic review of PubMed and Cochrane databases was conducted for articles from inception to July 2023. Eligible studies included reviews, clinical trials, and real-world analyses. Irrelevant studies were excluded, and manual searches and citation reviews were performed. Factors such as MTX exposure, drug interactions, demographics, serum albumin, urine pH, serum calcium, and genetic polymorphisms affecting MTX transport (e.g. SLCO1B1), intracellular folate metabolism (MTHFR), cell development (ARID5B), metabolic pathways (UGT1A1, PNPLA3), as well as epigenetics were identified. EXPERT OPINION: This comprehensive review aids researchers and clinicians in early identification of HDMTX toxicity risk factors. By understanding the multifaceted risk factors associated with hematologic malignancies, personalized treatment approaches can be tailored to optimize therapeutic outcomes.

Factors influencing delayed high-dose methotrexate excretion and its correlation with adverse reactions after treatment in children with malignant hematological tumors.

Background: High-dose methotrexate (HDMTX) is crucial in treating pediatric malignant hematological tumors. However, its use is often complicated by delayed excretion and associated adverse reactions, which can significantly affect treatment outcomes and patient safety. Identifying risk factors is essential for safer, more effective therapy. This study aimed to investigate the influencing factors for delayed excretion and their correlation with adverse reactions in children with malignant hematological tumors after receiving HDMTX chemotherapy. Methods: From April to October 2021, the clinical information of children who had undergone HDMTX chemotherapy and had their blood tested for drug concentration was gathered by the Department of Hematology and Oncology at Shanghai Children's Medical Center. Via univariate and multivariate logistic regression, the factors affecting the delayed excretion of HDMTX were examined, and the relationship between delayed excretion and unfavorable effects in children was determined. Results: This study included 99 patients comprising 199 courses of HDMTX. The occurrence rate of HDMTX delayed excretion was 20.1%. Age ≥9 years and a 24-hour methotrexate (MTX) concentration of 64 µmol/L were independent risk factors for delayed MTX excretion according to multivariate logistic regression analysis (P<0.05). Negative side effects, such as fever, infection, mucositis, gastrointestinal response, and decreased platelet count in children with delayed excretion were statistically significant when compared to those of children with normal excretion. White blood cell reduction, hemoglobin levels below 65 g/L, MTX excretion delay, and concomitant etoposide treatment were all independent risk factors for infection in children. Conclusions: To estimate the risk of delayed MTX excretion during HDMTX therapy, patient laboratory data should be scrutinized, especially for patients ≥9 years or those with a 24-hour MTX concentration of greater than 64 µmol/L.

Acetazolamide for acute kidney injury in patients undergoing high dose methotrexate therapy: a systematic review and meta-analysis.

BACKGROUND: Urine alkalization is one of the standard treatments to prevent acute kidney injury in patients receiving high-dose methotrexate. Carbonic anhydrase inhibitors are promising adjuvants/substitutes with advantages such as faster urine alkalization time and prevention of fluid overload. However, there is limited and contradictory evidence on its efficacy and safety. We aimed to compare the efficacy and safety of carbonic anhydrase inhibitors to standard treatments in adult patients receiving high-dose methotrexate. METHODS: The protocol was registered at PROSPERO (CRD42022352802) in August 2021. We evaluated the use of carbonic anhydrase inhibitors in combination with standard treatment compared to standard treatment alone. We excluded articles irrelevant to the efficacy and safety of acetazolamide in patients receiving high dose methotrexate and/or did not provide sufficient data regarding doses, recruitment criteria, and follow-up period. Two authors performed the data extraction independently. RESULTS: Among 198 articles retrieved, six observational studies met all eligibility criteria. Four studies with five datasets (totaling 558 patients/cycles) had enough data to be included in the meta-analysis. We independently report the results from the two remaining studies. The results did not show a significant difference between acetazolamide versus standard treatment in acute kidney injury (AKI) rate (OR = 0.79, 95% CI 0.48-1.29, P = 0.34, I2 = 0%). Regarding the time to urine pH goal, there was no significant time difference between the two groups (Mean Difference = 0.07, 95% CI - 1.9 to 2.04, P = 0.95, I2 = 25%). Furthermore, our meta-analysis showed that acetazolamide did not reduce length of stay (Mean Difference = 0.75, 95% CI - 0.8 to 2.31, P = 0.34, I2 = 0%). In one study, the only reported side effect of acetazolamide was hypokalemia (nearly 50% in the acetazolamide group). CONCLUSIONS: This systematic review showed no significant difference between acetazolamide and standard care treatment regarding urine alkalinization time and AKI rate in adult patients receiving high dose methotrexate. We suggest performing a large blinded, randomized, controlled trial to evaluate the potential benefits of this low-cost medication.

Correlation between gene polymorphism and adverse reactions of high-dose methotrexate in osteosarcoma patients: a systematic review and meta-analysis.

OBJECTIVE: We aimed to provide a reference based on evidence for an individualized clinical medication of high-dose methotrexate (HD-MTX) in osteosarcoma patients by evaluating the effect of gene polymorphism on adverse reactions of HD-MTX usage. METHODS: Several databases were combed for research on the association between gene polymorphisms and adverse reactions to HD-MTX up to January 2023. A meta-analysis and/or descriptive analysis on the incidence of HD-MTX-related adverse reactions were conducted by using clinical studies meeting inclusion criteria. RESULTS: Twelve studies involving 889 patients were included. There were 8, 6, 5, and 4 studies related to MTHFR C677T, MTHFR A1298C, RFC1 G80A, and MDR1 C3435T polymorphisms, respectively. The results of the meta-analysis showed that the MTHFR C677T polymorphism was associated with G3-4 hepatotoxicity, G3-4 nephrotoxicity, G3-4 gastrointestinal toxicity, and G3-4 mucositis under the recessive genetic model (MM vs. Mm/mm). Limited research showed that MTHFR C677T was associated with G3-4 nephrotoxicity in the allelic genetic model (M vs. m). MTHFR A1298C polymorphism was associated with a decreased risk of adverse reactions to HD-MTX usage, without statistical significance. This review's descriptive analysis showed no significant correlation between the RFC1 G80A, and MDR1 C3435T polymorphism and adverse reactions of HD-MTX. CONCLUSION: The MTHFR C677T mutation may enhance the risk of HD-MTX adverse reactions in osteosarcoma patients. Existing studies have not found a significant correlation between the MTHFR A1298C, RFC1 G80A, and MDR1 C3435T polymorphism and adverse reactions caused by HD-MTX. Lastly, this conclusion was limited because of few studies.

A Delphi study to determine the epidemiology and clinical management of patients treated with HDMTX who develop methotrexate (MTX) delayed elimination in France, Germany, Italy, and the UK.

Introduction: High-dose methotrexate (HDMTX) is administered for the treatment of some malignancies. Serious complications after the administration of HDMTX are rare, but occasionally MTX may precipitate in the renal tubes causing a delayed elimination leading to renal, multiorgan toxicities and to life-threatening complications. This study aims to estimate the incidence and clinical management of delayed MTX elimination in France, Germany, Italy, and the UK. Methods: Twelve haemato-oncology and pediatric oncology clinical experts from leading European hospitals participated in the study. A two-round Delphi methodology was used to gather data on different variables relevant to evaluate the HDMTX induced-toxicity impact. For quantitative data, median and interquartile ranges were calculated. Data on prevalence was calculated considering the number of patients in each hospital and the population they cover, and then, extrapolated to the country population. Results: The total number of patients treated annually with HDMTX in France, Germany, Italy, and the UK is estimated in 7155. Of these, 16% are estimated to develop delayed MTX elimination and around 9% may develop HDMTX-induced acute kidney injury (AKI). Leucovorin, hyperhydration and urine alkalinization are applied to prevent MTX toxicity and precipitation whilst glucarpidase, hemofiltration and hemodialysis are being used for persisting toxic MTX serum levels. Grade 3 systemic toxicities are common in these patients, hematologic and gastrointestinal being the most common ones. Conclusions: This report provides expert clinical practice experience and opinion of the incidence and management of HDMTX-delayed elimination in France, Germany, Italy and the UK, thereby contributing to the evidence available on this relevant medical condition which can be life-threatening.

Comparison of standardized prophylactic high-dose and intrathecal methotrexate for DLBCL with a high risk of CNS relapse.

The efficacy of high-dose methotrexate (HD-MTX) for central nervous system (CNS) relapse prophylaxis in patients with high-risk diffuse large B-cell lymphoma (DLBCL) is controversial. We compared the prophylactic effects of HD-MTX and intrathecal methotrexate (IT-MTX) on CNS relapse in high-risk DLBCL, in a multicenter retrospective study. A total of 132 patients with DLBCL at high risk of CNS relapse who received frontline chemotherapy and IT-MTX from 2003 to 2013 (n = 34) or HD-MTX from 2014 to 2020 (n = 98) were included. After a median follow-up of 52 months (range: 9-174), 11 patients had isolated CNS relapse: six (6.1%) in the HD-MTX group and five (14.7%) in the IT-MTX group. The median time until CNS relapse was 38 months (range: 11-122), and the cumulative incidence of CNS relapse at 3 years was 3.9% in the HD-MTX group and 6.1% in the IT-MTX group (P = 0.93). Similar results were obtained after adjusting for background factors using propensity score-matched analysis (4.5% HD-MTX vs. 7.6% IT-MTX, P = 0.84). The CNS relapse rate in HD-MTX-treated patients was equivalent to that in IT-MTX patients, demonstrating that HD-MTX was not superior to IT-MTX in preventing CNS relapse.

Access to Methotrexate Monitoring in Latin America: A Multicountry Survey of Supportive Care Capacity.

High-dose methotrexate (HDMTX) is used to treat a broad spectrum of cancers. Methotrexate (MTX) monitoring and adequate supportive care are critical for safe drug administration; however, MTX level timing is not always possible in low- and middle-income countries. The aim of this study was to evaluate HDMTX supportive care capacity and MTX monitoring practices in Latin America (LATAM) to identify gaps and opportunities for improvement. A multicenter survey was conducted among LATAM pediatric oncologists. Twenty healthcare providers from 20 institutions answered the online questionnaire. HDMTX was used to treat acute lymphoblastic leukemia (ALL; 100%), non-Hodgkin lymphoma (84.2%), diffuse large B-cell lymphoma (47.4%), osteosarcoma (78.9%), and medulloblastoma (31.6%). Delays in starting HDMTX infusion were related to bed shortages (47.4%) and MTX shortages (21.1%). MTX monitoring was performed at an in-hospital laboratory in 52%, at an external/nearby laboratory in 31.6%, and was not available in 10.5%. Median interval between sampling and obtaining MTX levels was ≤ 2 h in 45% and ≥ 6 h in 30%, related to laboratory location. Sites without access to MTX monitoring reduced the MTX dose for patients with high-risk ALL or did not include MTX in the treatment of patients with osteosarcoma. Respondents reported that implementation of point-of-care testing of MTX levels is feasible. In LATAM, highly variable supportive care capacity may affect the safe administration of MTX doses. Improving accessibility of MTX monitoring and the speed of obtaining results should be prioritized to allow delivery of full doses of MTX required by the current protocols.

Primary central nervous system lymphoma.

Primary central nervous system lymphoma (PCNSL) is a rare type of non-Hodgkin lymphoma (NHL) manifesting in the brain, spinal cord, cerebrospinal fluid and/or eyes, in the absence of systemic manifestations. With an increasing incidence and a 30% 5-year overall survival if promptly treated, timely diagnosis and subsequent treatment is paramount. The typical MRI appearance for PCNSL is a solitary or multiple T2-hypointense, homogeneous gadolinium-enhancing lesion with restricted diffusion. Dexamethasone treatment might compromise and delay the diagnosis. Hallmark of treatment is induction with intravenous high-dose methotrexate consisting polychemotherapy followed by consolidation treatment. Consolidation treatment consists of either whole brain radiotherapy (WBRT) or autologous stem cell transplantation (ASCT). Given the (cognitive) side effects of WBRT, ASCT is increasingly being used as the first choice of treatment.

Primary breast diffuse large B-cell lymphoma in the rituximab era: A retrospective study of the Chinese Southwest Oncology Group.

BACKGROUND: Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is a rare subtype of extranodal DLBCL, and the standard treatment remains controversial. In this study, we aimed to define the optimal treatment management in the rituximab era. METHODS: A total of 5089 newly diagnosed DLBCL patients treated with rituximab-containing immunochemotherapy between 2008 and 2019 from the Chinese Southwest Oncology Group-affiliated institutes were identified, of whom 135 diagnosed with PB-DLBCL were eligible for this analysis. RESULTS: PB-DLBCL accounted for 2.7% of all DLBCLs. With a median follow-up of 4.2 years, the 5-year overall survival and progression-free survival rates were 84.8% and 71.6%, respectively. Breast and central nervous system (CNS) relapses were the main cause of treatment failure. We observed that consolidative breast radiotherapy (RT) significantly decreased breast relapse risk (5-year risk, 2.9% vs. 20.1%, p = 0.007). The CNS relapse risk was lower for patients who received high-dose methotrexate (HD-MTX) than for patients who did not (5-year risk, 0% vs. 15.2%, p = 0.015). We further screened the genetic mutation profile of 20 patients from two institutes, and found that MYD88 (25%) and CD79B mutations (25%) frequently occur in PB-DLBCL. In addition, four patients with MYD88 and/or CD79B mutations experienced CNS relapse, while three patients with MYD88 and/or CD79B mutations who received HD-MTX did not experience CNS relapse. CONCLUSION: Collectively, our results indicate combined modality therapy including rituximab-containing immunochemotherapy and consolidative breast RT is a promising approach for PB-DLBCL, while HD-MTX is useful for preventing CNS relapse.

Different patterns of failure in two treatment regimens for primary central nervous system lymphoma, a retrospective analysis of 124 cases in Taiwan.

To explore prognostic factors and outcomes of primary central nervous system lymphoma (PCNSL) of diffuse large B-cell lymphoma (DLBCL) in Taiwan, 124 PCNSL-DLBCL patients (from 1995 to 2021) were retrospectively analyzed. Mainly, two treatment modalities including sandwich chemoradiotherapy and modified MATRix regimen were employed in these patients. Overall survival (OS) was determined by log-rank test and time-dependent Cox analysis. Median OS of all patients was 27.1 months. 47 (37.9%) patients who underwent sandwich chemoradiotherapy had a complete remission (CR) rate of 87.2%, median OS of 53.9 months, and progression free survival (PFS) of 42.9 months. 11 (8.9%) patients who underwent modified MATRix regimen had CR rate of 72.7%, median OS of 18.9, and PFS of 11.2 months. There are no significant OS differences between treatment groups or addition of Rituximab. Patients treated with the modified MATRix regimen experienced a higher early mortality rate followed by a survival plateau. IELSG low-risk group had significantly improved OS and PFS than IELSG intermediate- or high-risk group. In multivariant analysis, age > 60 years old and bilateral cerebral lesions are associated with significantly inferior OS. Sandwich chemoradiotherapy demonstrated better early survival and reduced treatment-related toxicity for PCNSL patients compared to the modified MATRix regimen. However, the long-term follow-up revealed a higher rate of treatment failure events in the sandwich chemoradiotherapy group. IELSG and MSKCC scores served as reliable risk assessment models. Incorporating bilateral cerebral lesions as a risk factor further improved risk evaluation.

High-Dose Methotrexate: Nursing Considerations for Administration and Supportive Care.

BACKGROUND: High-dose methotrexate (HDMTX) is the backbone of many pediatric and adult oncology treatment protocols. It requires appropriate monitoring and supportive care because delayed elimination of MTX can lead to serious toxicities. No reviews specifically addressing nursing management regarding standard treatment protocols and delayed MTX elimination exist. OBJECTIVES: This article provides an overview of HDMTX treatment and nursing considerations, including toxicities, components of supportive care management, and strategies to manage administration and delayed elimination of MTX. METHODS: A review of published literature and guidelines was performed to evaluate nursing considerations for patients receiving HDMTX. FINDINGS: Using existing and novel tools, nurses can closely monitor patients and provide supportive care to mitigate HDMTX toxicity. Early identification of delayed MTX elimination and subsequent treatment with glucarpidase, if appropriate, has been associated with shorter length of hospital stay and decreased incidence of grade 4 toxicities and mortality.

Model for Predicting Central Nervous System Relapse in Diffuse Large B-Cell Lymphoma and Discussion of Prophylaxis Measures.

OBJECTIVE: Relapse of the central nervous system (CNS) is a rare but fatal complication in diffuse large B-cell lymphoma (DLBCL). The purpose of this study is to learn how to identify high-risk patients and take effective preventive measures. METHODS: We retrospectively analyzed 1,290 adult patients with DLBCL at Peking University Cancer Hospital and Shanxi Bethune Hospital between 2010 and 2020. RESULTS: There were 55 patients with CNS relapse who had a median follow-up of 5 years. The risk of CNS relapse was 1.58% in the low-risk group, 5.66% in the moderate-risk group, and 11.67% in the high-risk group based on CNS International Prognostic Index (CNS-IPI). We found that CNS-IPI and testicular involvement were risk factors for CNS relapse, with OR 1.913 (95% CI: 1.036∼3.531; P = 0.038) versus. OR 3.526 (95% CI: 1.335∼9.313; P = 0.011), respectively. Intrathecal MTX and/or cytarabine prophylaxis was used in 166 patients (13.94%), intravenous (IV) high-dose methotrexate (HD-MTX) prophylaxis in 8 patients (0.67%), and intrathecal plus intravenous prophylaxis in 15 patients (1.26%). There was no significant difference in CNS relapse risk between IT, HD-MTX, and no prophylaxis recipients (12.7% vs. 0% vs. 23.6%, respectively, P = 0.170). The risk of CNS relapse was similar whether or not patients accepted prophylaxis (5-year risk 4.1% vs. 2.2%, P = 0.140). CONCLUSIONS: Central nervous system (CNS) relapse is associated with high risk CNS-IPI and testicular involvement. Therefore, it is necessary to pursue novel prophylactic strategies for CNS relapse.

A retrospective study of 222 patients with newly diagnosed primary central nervous system lymphoma-Outcomes indicative for improved survival overtime.

Primary central nervous system lymphoma (PCNSL) is a rare disease with an incidence of 0.4/per 100,000 person-years. As there is a limited number of prospective randomized trials in PCNSL, large retrospective studies on this rare disease may yield information that might prove useful for the future design of randomized clinical trials. We retrospectively analyzed the data of 222 newly diagnosed PCNSL patients treated in five referral centers in Israel between 2001 and 2020. During this period, combination therapy became the treatment of choice, rituximab has been added to the induction therapy, and consolidation with irradiation was largely laid off and was mostly replaced by high-dose chemotherapy with or without autologous stem cell transplantation (HDC-ASCT). Patients older than 60 comprised 67.5% of the study population. First-line treatment included high-dose methotrexate (HD-MTX) in 94% of patients with a median MTX dose of 3.5 g/m2 (range 1.14-6 g/m2 ) and a median cycle number of 5 (range 1-16). Rituximab was given to 136 patients (61%) and consolidation treatment to 124 patients (58%). Patients treated after 2012 received significantly more treatment with HD-MTX and rituximab, more consolidation treatments, and autologous stem cell transplantation. The overall response rate was 85% and the complete response (CR)/unconfirmed CR rate was 62.1%. After a median follow-up of 24 months, the median progression-free survival (PFS) and overall survival (OS) were 21.9 and 43.5 months respectively with a significant improvement since 2012 (PFS: 12.5 vs. 34.2 p = 0.006 and OS: 19.9 vs. 77.3 p = 0.0003). A multivariate analysis found that the most important factors related to OS were obtaining a CR followed by rituximab treatment and Eastern Cooperative Oncology Group performance status. The observed improvement in outcomes may be due to multiple components such as an intention to treat all patients regardless of age with HD-MTX-based combination chemotherapy, treatment in dedicated centers, and more aggressive consolidation with the introduction of HDC-ASCT.

External evaluation and systematic review of population pharmacokinetic models for high-dose methotrexate in cancer patients.

Several population pharmacokinetic (PPK) models have been established to optimize the therapeutic regimen and reduce the toxicity of high-dose methotrexate (HDMTX) in patients with cancer. However, their predictive performance when extrapolated to different clinical centers was unknown. In this study, we aimed to externally evaluate the predictive ability of HDMTX PPK models and determine the potential influencing factors. We searched the literature and determined the predictive performance of the selected models using methotrexate concentrations in 721 samples from 60 patients in the First Affiliated Hospital of the Navy Medical University. Prediction-based diagnostics and simulation-based normalized prediction distribution errors (NPDE) were used to evaluate the predictive performance of the models. The influence of prior information was also assessed using Bayesian forecasting, and the potential factors affecting model predictability were investigated. Thirty models extracted from published PPK studies were assessed. Prediction-based diagnostics showed that the number of compartments potentially influenced model transferability, and simulation-based NPDE indicated model misspecification. Bayesian forecasting significantly improved the predictive performance of the models. Various factors, including bioassays, covariates, and population diagnosis, influence model extrapolation. The published models were unsatisfactory for all prediction-based diagnostics, except for the 24 h methotrexate concentration monitoring and simulation-based diagnostics, making them inappropriate for direct extrapolation. Moreover, Bayesian forecasting combined therapeutic drug monitoring could improve the predictive performance of the models.