Cycles Of Methotrexate Research Articles

Eight-year national multicenter experience on the use of glucarpidase as effective rescue therapy for delayed methotrexate elimination after high-dose methotrexate cycles administered in children with hemato-oncological diseases

BackgroundHigh-dose methotrexate (HDMTX) for cancer treatment can be complicated by delayed methotrexate elimination (DME) and associated acute kidney injury (AKI). This study evaluated glucarpidase for the treatment of DME and HDMTX-AKI in pediatric hemato-oncology patients. MethodsThis multicenter, retrospective study reviewed the medical records of pediatric patients (1–18 years) with ALL or NHL, who were given glucarpidase as rescue therapy for DME or HDMTX-AKI at 13 Italian AIEOP centers between January 1, 2015, and June 30, 2023. Patients also received uniform supportive therapy, per study protocols and guidelines, to prevent and treat AKI. ResultsData were available for 42/44 patients given glucarpidase, following i.v. HDMTX as monotherapy (non-high risk ALL [non-HR ALL], n=24), or within combined intensive chemotherapy blocks (HR-ALL, n=13; NHL, n=5). Median time to glucarpidase infusion was 53hours (range 32–72). Most patients required glucarpidase during the first cycle of HDMTX. Glucarpidase led to a rapid decrease in plasma MTX levels (median 72.53%; range 12.62%–94.57%). Median time for complete elimination of MTX and its metabolites was 216hours (range 120–672). Recovery of renal function (return of serum creatinine to ≤1.5 times baseline value) took a median 18 days (range 4–72). Of the 22/42 patients (52%) re-challenged with HDMTX (at 40–100% of recommended dose), none experienced DME and all completed per-protocol number of HDMTX cycles. ConclusionsOur experience shows that glucarpidase is effective and well tolerated for the treatment of DME and HDMTX-AKI in pediatric patients with hemato-oncologic diseases.

Anticipating Leucovorin Rescue Therapy in Patients with Osteosarcoma through Methotrexate Population Pharmacokinetic Model.

Methotrexate (MTX), which presents high inter-individual variability, is part of the Brazilian Osteosarcoma Treatment Group (BOTG) protocol. This work aimed to develop a MTX population pharmacokinetic model (POPPK) for Brazilian children with osteosarcoma (OS) following the BOTG protocol to guide rescue therapy and avoid toxicity. The model was developed in NONMEM 7.4 (Icon®) using retrospective sparse data from MTX therapeutic drug monitoring of children attending a southern Brazilian public reference hospital. Data were described by a two-compartment model using 216 MTX cycles from 32 patients (5-18 y.o.) with OS who received 12 g/m2 dose/cycle. To explain inter-individual and inter-occasion variability in clearance and peripheral volume, covariates from demographic and biochemical data were evaluated. Serum creatinine was a significant covariate of MTX clearance (14.8 L/h), and the body surface area (BSA) was significant for central compartment volume (82.5 L). Inter-compartmental clearance and volume of peripheral compartment were 0.178 L/h and 5.72 L, respectively. The model adequately describes MTX exposure in Brazilian children with OS. Successful simulations were performed to predict MTX concentrations in pediatric patients above five years old with acute kidney injury and anticipate rescue therapy adjustments.

CTNI-83. MATRIX REGIMEN FOR NEWLY DIAGNOSED PRIMARY CNS DIFFUSE B-CELL LYMPHOMA

Abstract We report our experience treating 25 patients with newly diagnosed primary CNS diffuse B-cell lymphoma with the MATRix regimen as reported by Ferreri, et al in 2016. The median age was 66 y (range 30-85); 12 patients were men and 13 were women. Twenty-three had cerebral mass lesions, 1 had a paraspinal mass, and 1 leptomeningeal disease. Treatment consisted of 4 cycles of rituximab 375 mg/sq m (Days 1, 6); methotrexate 3.5 g/sq m (Day 2); cytarabine 2 g/sq m every 12 h (Days 3, 4); and thiotepa 30 mg/sq m (Day 5). Patients without disease progression received carmustine 400 mg/sq m and thiotepa 5 mg/kg followed by autologous bone marrow transplantation. Four patients were switched to MATRix after 6 cycles of methotrexate and rituximab and received only 2 initial cycles including cytarabine and thiotepa. Overall, 18 patients completed initial chemotherapy. Sixteen of these 18 went on to transplantation; one patient had had early disease progression, and in one no stem cells could be collected. Five patients (median 73 y; range 64-85 y) died early after 1-2 cycles. The causes of early death were neutropenic fever, septic thrombophlebitis, and cardiac arrest. One of the 16 patients who completed the entire regimen including transplantation died of fungal pneumonia and the other 15 experienced no serious acute toxicity. One patient had late disease progression and 2 developed symptomatic leukoencephalopathy. Seventeen of the 25 patients remain alive. Median TTP for the cohort is 605 days, and OS 738 days. These preliminary data suggest that the MATRix regimen in safe and highly effective in the newly diagnosed setting. However, the high incidence of early death in patients over 65 y shows that the regimen is too toxic for older individuals.

Real-World Experience with RTOG 0227 Induction for First Line Therapy of Primary CNS Lymphoma (PCNSL)

Introduction PCNSL is an aggressive and rare subtype of extranodal non-Hodgkin Lymphoma affecting the brain, spinal cord, cerebrospinal fluid (CSF), leptomeninges and/or vitreoretinal components. While there have been trials comparing outcomes of consolidation treatment with whole brain radiation therapy (WBRT) versus (vs) autologous hematopoietic cell transplantation (auto-HCT) following different induction regimens in PCNSL, the optimal induction regimen to pair with these forms of consolidation remains controversial. Our group adopted a modified version of the RTOG 0227 induction as our standard PCNSL induction in 2017. This regimen includes 5 cycles of Methotrexate (MTX) at 3.5 g/m 2 and Rituximab (R) at 375-500 mg/m 2, and Temozolomide (TMZ) on cycles 2 and 4. Based on the published phase 2 trial of 53 patients (pts), the regimen is significantly less toxic than more aggressive induction regimens such as MATRiX, especially in older pts or those with comorbidities. We evaluated our real-world outcomes in PCNSL pts treated with RTOG 0227 induction followed by consolidation with either WBRT/TMZ or auto-HCT, at a single academic university hospital. Methods We identified newly diagnosed PCNSL pts treated at a single academic university hospital between 2017 and 2023. Electronic medical records were retrospectively reviewed to collect data including demographics, clinicopathological features, treatment details, response rates, long-term follow up, disease recurrence, and survival. The IELSG prognostic index tool was used for risk assessment. All pts received induction regimen consisting of R (dose between 375- 500 mg/m 2) and 3.5 g/m 2 of MTX with leucovorin on weeks 1, 3, 5, 7 and 9 along with TMZ daily for 5 days on weeks 4 and 8, followed by consolidation with either WBRT/TMZ or auto-HCT. In WBRT cohort, maintenance TMZ was given at 200mg/m 2 daily for 5 days every 28 days, for total of 10 cycles, and dose was reduced if side effects developed. Objective response rate (ORR) and complete response rate (CRR) after induction chemotherapy were calculated. Overall survival (OS) and progression free survival (PFS) at 2 years were estimated with the Kaplan-Meir method (using GraphPad Prism 9.3.1) and compared between the WBRT and auto-HCT cohorts, using the log-rank test. Results A total of 29 PCNSL pts were included in the study. Patient and disease characteristics for the entire cohort, as well as pts treated with WBRT vs auto-HCT consolidation, are shown on the Table. On average (avg), pts received 4 cycles of MTX and 8 cycles of TMZ. Nine (31%) pts developed acute kidney injury and 1 (3.4%) developed transaminitis from MTX. The avg total cumulative TMZ dose was 5913 mg/m 2 and 8 (27.5%) pts required TMZ dose reduction. Treatment related mortality (TRM) following induction was 0%. Eight (27.5%) pts had complete response, 19 (65.5%) had partial response, 1 (3.5%) had stable disease and 1 (3.5%) had disease progression. ORR was 93.1% and CRR was 27.5%. Eighteen (62%) pts received WBRT/TMZ consolidation, while 11 (38%) received auto-HCT consolidation. Median dose of WBRT administered was 36 Gy (23.4 to 36 Gy). Thirteen (72.2%) pts received 36 Gy in 30 fractions (fx) of 1.2 Gy BID, 4 (22.2%) pts received 23.4 Gy in 13 fx of 1.8 Gy OD, and 1 (5.5%) pt received 30.6 Gy in 17 fx of 1.8 Gy OD. Most common conditioning regimen prior to auto-HCT was carmustine/thiotepa (BCNU/TT). With a median follow up of 36 months, 4 (22.2%) pts in WBRT cohort and 1 (9.1%) in auto-HCT cohort had disease recurrence. Two-year PFS was 83% overall, 81% for the WBRT pts and 87% for the auto-HCT pts, with a p value of 0.65 for log-rank comparison of PFS for the WBRT vs auto-HCT pts. Two-year OS was 96% for the entire cohort, 94% for the WBRT pts and 100% for the auto-HCT pts, with a p value of 0.27 for log-rank comparison of OS for the WBRT vs auto-HCT pts. Conclusion In this real-world cohort of PCNSL pts not treated as part of a clinical trial, we observed excellent outcomes using the modified RTOG 0227 induction regimen. PFS and OS at 2 yrs in our cohort exceeds those reported with any prospective clinical trial to date, and with zero TRM to date. This data indicates that the modified RTOG 0227 induction with either WBRT or auto-HCT consolidation represents a very tolerable and highly effective option for first line therapy of PCNSL, for both younger and older pts.

Flat-dose versus weight or body surface area-based methotrexate dosing in low-risk gestational trophoblastic neoplasia

BackgroundSingle-agent methotrexate (MTX) is commonly used as first-line treatment for low-risk gestational trophoblastic neoplasia (LR-GTN), although no international consensus exists on the optimal treatment regimen to maximise complete hCG response (CR) and minimise relapse rates. Current regimens differ in the route of administration, dose scheduling, and use of flat-dose, body surface area (BSA)- or weight-based dosing. In the UK a methotrexate-folinic acid (MTX-FA) 8-day 50 mg intramuscular flat-dose regimen is used, with 15 mg oral folinic acid rescue. In LR-GTN patients, we aim to determine the effect of MTX dose adjustment by BSA and weight upon chemotherapy response and disease relapse. MethodsBetween January 1973 and August 2020, 935 LR-GTN patients treated with first-line MTX-FA were identified from a single UK specialist trophoblastic centre. Of these, 364 were included, of which 178 (49%) had a CR to first-line MTX-FA. Subgroup analyses were performed upon: (i) patients who changed chemotherapy due to MTX toxicity (n = 33); and (ii) patients with a FIGO score of 5–6 (n = 85). Logistic regression analysis explored the relationship between BSA or weight adjusted MTX dosing and: (i) CR to first-line chemotherapy; (ii) incidence of disease relapse. Linear regression analyses assessed the correlation of BSA and weight with the number of MTX-FA cycles required to achieve CR. ResultsIn LR-GTN patients, BSA and weight adjusted MTX-FA dosing did not influence CR to first-line chemotherapy or the incidence of disease relapse. The number of MTX cycles required to achieve CR was not associated with BSA or weight. These findings were maintained in a subgroup analysis of FIGO 5–6 patients. The incidence of MTX toxicity was not influenced by BSA or weight. ConclusionsIn the treatment of LR-GTN, dose individualisation using BSA or weight is not required, and fixed dosing continues to be preferred as the UK standard.

CTNI-59. MATRIX REGIMEN FOR NEWLY DIAGNOSED PRIMARY CNS DIFFUSE B-CELL LYMPHOMA

Abstract We report our experience treating 22 patients with newly diagnosed primary CNS diffuse B-cell lymphoma with the MATRix regimen as reported by Ferreri, et al in 2016. The median age was 64 y (range 45-85); 10 patients were men and 12 were women. Twenty had cerebral mass lesions, 1 had a paraspinal mass, and 1 leptomeningeal disease. Treatment consisted of 4 cycles of rituximab 375 mg/sq m (Days 1, 6); methotrexate 3.5 g/sq m (Day 2); cytarabine 2 g/sq m every 12 h (Days 3, 4); and thiotepa 30 mg/sq m (Day 5). Patients without disease progression received carmustine 400 mg/sq m and thiotepa 5 mg/kg followed by autologous bone marrow transplantation. Four patients were switched to MATRix after 6 cycles of methotrexate and rituximab and received only 2 initial cycles including cytarabine and thiotepa. Overall, 16 patients completed initial chemotherapy. Fourteen of these 16 went on to transplantation; one patient had had early disease progression, and in one no stem cells could be collected. Five patients (median 73 y; range 64-85 y) died early after 1-2 cycles. The causes of early death were neutropenic fever, septic thrombophlebitis, and cardiac arrest. One patient who completed the entire regimen including transplantation died of fungal pneumonia and the other 13 experienced no serious acute toxicity. One patient had late disease progression and one developed symptomatic leukoencephalopathy. Fourteen of the 22 patients remain alive. Median OS for the cohort is 663 days. These preliminary data suggest that the MATRix regimen in safe and highly effective in the newly diagnosed setting. However, the high incidence of early death in patients over 65 y suggests that the regimen may be too toxic for older individuals.

Urinary potassium and association with methotrexate (MTX) elimination delay in patients with primary central nervous system lymphoma (PCNSL).

e14045 Background: First-line treatment of PCNSL consists in a polychemotherapy based on high-dose MTX with hyperhydratation until MTX elimination. Renal toxicity remains frequent with pejorative impact on renal function and patient survival. Our objective was to determine urinary predictive factors of MTX elimination delay. Methods: Patients with PCNSL followed in our institution were prospectively recruited from December 2020 to May 2021. Daily serum and urinary creatinine and ionogram were collected from the day before MTX administration until elimination. Patients characteristics, biological data and MTX concentration were recorded. Normal elimination time was defined by MTX ≤ 0.05 at 72 hours. Results: We collected data from 64 MTX cycles corresponding to 20 patients. Median age was 71 years (range, 33 - 86) and median Karnofsky Performance Status (KPS) was 70. Forty-four percent of cycles were full dose (3500 mg/m2). Median urinary osmolarities one day before, the day and 24 hours after MTX administration were 325 mOsm (range, 62 - 542), 316 mOsm (range, 58 - 671) and 291 mOsm (range, 56 - 554), respectively. Median time for MTX elimination was 94.7 hours (range, 47 - 205). Only one patient needed to receive MTX antidote (glucarpidase). The factors significantly associated with MTX elimination time were age (p < 0.001), KPS (p < 0.001) and urinary K+ concentration at 24 hours post MTX administration (u-K+) (p = 0.008). Using ROC curve analyses, we determine optimal cutoffs for age (80 years, p < 0.001, AUC = 0.825), KPS (70, p < 0.001, AUC = 0.808) and u-K+ (17.2 mmol/L, p = 0.008 AUC = 0.712). This u-K+ cutoff presented with a specificity of 81% and a sensibility of 60%. Focusing on patients aged < 80 years (52 cycles / 64), we confirmed that both KPS (p = 0.022) and u-K+ (p = 0.027) were significantly correlated with MTX elimination time by multivariate analysis. Then, we derived a 3-factors score including 5 subgroups: 1) aged ≥ 80 (N = 12); 2) age < 80, KPS < 70 and high u-K+ (N = 11); 3) age < 80, KPS < 70 and low u-K+ (N = 6); 4) age < 80, KPS ≥ 70 and high u-K+ (N = 8); 5) age < 80, KPS≥70 and low u-K+ (N = 21). The median times for MTX elimination were 112, 96, 95, 82 and 72 hours respectively. The normal elimination rates in each subgroup were 17%, 0%, 17%, 37% and 71% respectively. Conclusions: Age, KPS and u-K+ were correlated with MTX elimination time. We derived a predictive score based on these items that could be used in routine to anticipate MTX elimination delay and to potentially prevent the risk of renal toxicity. These results need to be prospectively confirmed in a larger cohort.

Prevalence and management of methotrexate-induced neurotoxicity in pediatric patients with osteosarcoma: a single-center experience.

To determine the incidence, clinical presentation, and outcome of methotrexate (MTX) associated neurotoxicity in pediatric patients treated for osteosarcoma, with the aim of identifying possible risk factors and suggesting recommended treatment for these sequelae. All medical files of patients treated for osteosarcoma in a single pediatric haemato-oncology center between November 2011 and August 2021 were retrospectively reviewed. All patients were treated according to the EURAMOS AOST0331 protocol, using cisplatin, doxorubicin, and high-dose MTX at a dose of 12g/m2 over 4h. Seventy-eight patients with osteosarcoma were identified (age range 5 to 23years, 42 males). Seven patients (9%) sustained neurotoxicity following treatment with high-dose MTX. Manifestations of neurotoxicity included among others, generalized seizures, confusion, encephalopathy, dysarthria, and choreiform movements. All but one episode occurred following two sequential cycles of high-dose MTX. All 7 had subacute toxicity, 5-10days following MTX administration, and 1 had both acute and subacute toxicity. Brain MRI was performed for all patients and demonstrated typical MRI changes attributed to MTX neurotoxicity in 4 of them. Two patients received aminophylline; one patient received dextromethorphan. Patients with normal MRI imaging resumed MTX therapy without any sequels. No risk factors were found for high-dose MTX-related toxicity occurrence. The time of risk of neurotoxicity due to high-dose MTX treatment for osteosarcoma is days 5-10 following two sequential treatment cycles. These findings together with treatment options for these adverse effects should be detailed in the therapeutic protocol of MTX use among pediatric patients with osteosarcoma.

CTNI-57. MATRix REGIMEN FOR NEWLY DIAGNOSED PRIMARY DIFFUSE B-CELL LYMPHOMA OF THE CENTRAL NERVOUS SYSTEM

Abstract We report our experience treating 20 patients with newly diagnosed primary diffuse B-cell lymphoma of the central nervous system with the MATRix regimen as reported by Ferreri, et al in 2016. The median age was 65 y; 8 patients were men and 12 were women. Eighteen had cerebral mass lesions, 1 had a paraspinal mass, and 1 leptomeningeal disease. Treatment consisted of 4 cycles of rituximab 375 mg/sq m (Days 1, 6); methotrexate 3.5 g/sq m (Day 2); cytarabine 2 g/sq m every 12 h (Days 3, 4); and thiotepa 30 mg/sq m (Day 5). Patients without disease progression received carmustine 400 mg/sq m and thiotepa 5 mg/kg followed by autologous bone marrow transplantation. Four patients were switched to MATRix after 6 cycles of methotrexate and rituximab and received only 2 initial cycles including cytarabine and thiotepa. Overall, 14 patients completed initial chemotherapy. Twelve of these 14 went on to transplantation; one patient had early disease progression, and in one no stem cells could be collected. All 4 patients over 70 y died early after 1-2 cycles; the median age of these was 80 y, and the causes of early death were neutropenic fever, septic thrombophlebitis, and cardiac arrest. One patient who completed the entire regimen including transplantation died of fungal pneumonia; the other 13 experienced no serious acute toxicity. One patient had late disease progression; one developed symptomatic leukoencephalopathy. Thirteen of the 20 patients remain alive. Median OS for the cohort is 698 days. These preliminary data suggest that the MATRix regimen in safe and highly effective in the newly diagnosed setting. However, the high incidence of early death in patients over 70 y suggests that the regimen may be too toxic for elderly individuals.

Administration and Toxicity Profile of the Capizzi Interim Maintenance—Retrospective Study from a Tertiary Care Cancer Centre

Abstract Introduction The Capizzi-style methotrexate (MTX) is an integral part of acute lymphoblastic leukemia (ALL) treatment. The escalating dose of MTX originally used in the United Kingdom and Children’s Oncology Group protocols along with L-asparaginase has been modified in the Indian Childhood Collaborative Leukemia (ICiCLe) group protocol where L-asparaginase has been omitted. The data regarding the incidence of toxicities and ease of administration on the Capizzi-style interim maintenance is not robust. Objectives We have compiled our experience with administration and toxicity profile in children with intermediate-risk ALL. Materials and Methods A retrospective data collection of all children diagnosed with intermediate-risk ALL as per the ICiCLe risk stratification in the year 2019 was included in the analysis. Each cycle of MTX was started after ensuring an absolute neutrophil count of >750/mm3 and transaminases <2 upper limit of normal. As a unit protocol, pre- and post-MTX hydration was administered in all our children. No urine pH or midcycle biochemical parameter monitoring was done. Statistical analysis was done using Microsoft Excel and SPSS version 24 IBM Corp. in Armonk, New York, United States. Results Forty-six children were included in the study. The median age of children in our study was 6 years (range: 1 year 2 months–12 years). Undernutrition was associated with a significant increase in toxicity (p = 0.02). Fifty-two percent of children had evidence of toxicity, elevated transaminases being the most common. There were recurring symptoms resulting in 53 episodes of toxicities overall. Incidence of toxicity was more in the early cycles (<3). Conclusion The pre- and post-MTX hydration is an effective way to reduce toxicities with the Capizzi-style MTX and this course can be administered with ease on outpatient basis with minimal need for monitoring or admission.

CTNI-64. MATRIX REGIMEN FOR NEWLY DIAGNOSED PRIMARY DIFFUSE B-CELL LYMPHOMA OF THE CENTRAL NERVOUS SYSTEM

Abstract We report our experience treating 16 patients with newly diagnosed primary diffuse B-cell lymphoma of the central nervous system with the MATRix regimen as reported by Ferreri, et al in 2016. The median age was 66 years (y); 8 patients were men and 8 were women. Fourteen had cerebral mass lesions, 1 had a paraspinal mass, and 1 leptomeningeal disease. Treatment consisted of 4 cycles of rituximab 375 mg/sq m (Days 1, 6); methotrexate 3.5 g/sq m (Day 2); cytarabine 2 g/sq m every 12 h (Days 3, 4); and thiotepa 30 mg/sq m (Day 5). Patients without disease progression received carmustine 400 mg/sq m and thiotepa 4 X 5 mg/kg followed by autologous bone marrow transplantation. Four patients were switched to MATRix after 6 cycles of methotrexate and rituximab and received only 2 initial cycles including cytarabine and thiotepa. Overall, 12 patients completed initial chemotherapy. Eleven of these 12 went on to transplantation; one patient had early disease progression and did not proceed to transplantation. All 4 patients over 70 y died early after 1–2 cycles; the median age of these was 80 y, and the causes of early death were neutropenic fever, septic thrombophlebitis, and cardiac arrest. One patient who completed the entire regimen including transplantation died of fungal pneumonia; the other 11 experienced no serious acute toxicity. One patient had late disease progression; one developed symptomatic leukoencephalopathy. Nine of the 16 patients remain alive. At a median follow-up of 23 months, median time to progression was 421 days and overall survival 564 days. These preliminary data suggest that the MATRix regimen in safe and highly effective in the newly diagnosed setting. However, the high incidence of early death in patients over 70 y suggests that the regimen may be too toxic for elderly individuals.

BMI Is Not Associated with Toxicity to High Dose Methotrexate: A Single Institution Retrospective Study of 147 Patients

Background: High-dose methotrexate (HD-MTX) with leucovorin rescue is frequently used in the treatment of various lymphomas, breast cancer, and sarcomas and remains an important therapy for lymphoma with CNS involvement. Despite its efficacy, HD-MTX can carry considerable toxicity which can lead to prolonged hospital stays, invasive therapies, and delays/discontinuation of a potentially curative treatments. Previous studies have shown that advanced age, male sex, use of proton pump inhibitors and impaired creatinine clearance are associated with higher rates of MTX toxicity (May et al 2014). However, the impact of body mass index (BMI) on the risk of toxicity with HD-MTX has not previously been reported. We performed a retrospective analysis of all patients at Washington University in St. Louis who were treated with HD-MTX to evaluate the relationship between BMI and risk of toxicity. Methods: Consecutively treated adult patients at Washington University in St. Louis who were treated with HD-MTX (>1,000mg/m2) for any malignancy (excluding leukemia) from 2005-2011 were identified via our pharmacy database. Baseline patient data was collected via retrospective review of the medical record including age, sex, diagnosis, methotrexate dose received, baseline renal and liver function tests, evidence for HD-MTX toxicity, concomitant medications. HD-MTX toxicity was defined as by delayed methotrexate clearance, acute kidney injury, liver function abnormalities, mucositis, or acute kidney injury, disease status and survival. Delayed methotrexate clearance was defined as serum methotrexate level of greater than 15umol/L at 24 hours, greater than 1.5umol/L at 48 hours, or greater than 0.15umol/L at 72 hours based on prior studies (May et al 2014). Results: 147 patients were included who received a total of 496 cycles of methotrexate (58 CNS lymphoma, 26 DLBCL, 11 T-cell lymphoma, 12 Burkitt's lymphoma, 2 mantle cell lymphoma, 27 sarcoma, 10 breast cancer, 1 other). 2 patients with B-ALL were excluded. The median age was 50 years (range 19-80) with 14 patients who were ≥70 years. Patients each received a median of 2.5 cycles of HD-MTX (range 1-12) at doses of ≤3.5g/m2 (n=248) and >3.5g/m2 (n=248). The total incidence of HD-MTX toxicity in this cohort was 52.4% (260/496 administrations) and did not differ between those who received doses ≤3.5g/m2 (n=248) or >3.5g/m2 (n=248) (OR: 0.875, 95% CI: 0.61-1.25). Median OS was not impacted by presence or absence of MTX toxicity (66 mo vs 84 mo p=0.78). Patients who experienced toxicity had longer clearance than those who did not (5.8 days vs 3.1 days, p=<0.001). Use of proton pump inhibitors was associated with a higher risk of MTX toxicity (OR 1.8, 95% CI: 1.25-2.6). Use of concomitant antibiotics (OR 1.024, 95% CI: 067-1.6) and age >70 (OR 0.64, 95% CI: 0.185-2.2) were not independent risk factors for HD-MTX toxicity. The median BMI of patients was 25.3 (range 14.7-44.9). 6.1%, 40.8%, 27.2%, and 25.9% had BMIs of underweight (<18.5), normal (18.5-25), overweight (25-30), obese (>30) respectively. We used the restricted cubic spline smoothing method to model the functional form of the association between BMI and MTX toxicity. We found that there is no significant association between BMI and MTX toxicity (p=0.898). The 95% confidence bands contain a flat line such that there is no associated change in the probability of having a MTX toxicity event for any given change in BMI. When comparing patients who had normal BMI or underweight compared to those who had BMIs above normal, there was no significant difference in the rate of methotrexate toxicity. Conclusions: In this cohort of patients treated with HD-MTX, we found that BMI is not a risk factor in the development of toxicity. Our analysis also suggests that a single incidence of HD-MTX toxicity does not significantly impact patient survival, which is similar with previous findings (May, Leukemia & Lymphoma 2013). Determining potential risk factors for HD-MTX toxicity will allow clinicians to be better prepared to manage complications and tailor treatment regimens based on individual patient characteristics. Disclosures Mehta-Shah: Genetech: Research Funding; Karyopharm Therapeutics: Consultancy; Bristol Myers-Squibb: Research Funding; C4 Therapeutics: Consultancy; Celgene: Research Funding; Innate Pharmaceuticals: Research Funding; Kyowa Kirin: Consultancy; Verastem: Research Funding.

Re-challenge with High Dose Methotrexate vs. Reduced Dose After Methotrexate Toxicity in Pediatric Osteosarcoma:Case Report

Introduction: Methotrexate (MTX), a classic antifolate, is one of the most widely used and well-studied anticancer agents. High-dose methotrexate (HD-MTX) with folinic acid (leucovorin) rescue is one of the standard therapies for osteosarcoma. High-dose methotrexate (HDMTX) can exert significant toxicity and requires complex pharmacokinetic monitoring and leucovorin rescue. The side effect profile of MTX varies markedly according to the dose. Regimens containing MTX are classified as high, intermediate, or low-dose. High-dose methotrexate (HD-MTX; 12 g/m2) is a part of the golden standard therapy for pediatric osteosarcoma (OS). Risk factors associated with MTX toxicity in children with OS are not well defined. Case Presentation: We report here a case of pediatric osteosarcoma with nephrotoxicity associated with delayed MTX excretion who was successfully managed using supportive measures that encouraged us to re-challenge with a full dose of MTX then we reduced the dose to 50% to attain the final critical decision about continuation or changing the regimen of treatment for the patient. Our patient developed moderate renal complications during therapy that improved with supportive care, so we challenged with more cycles of a high dose MTX, but the patient developed serious renal complications. A reduced dose of MTX with 50% was given successfully without any renal impairment. Conclusion: Methotrexate toxicity that might not occur during the initial courses of high-dose MTX is not a predictive of the tolerability of further courses and re-challenging with HDMTX is risky, but reduced dose methotrexate is a good option rather than changing the regimen, with good tolerability and rapid clearance of HDMTX. HDMTX-induced renal impairment occurs in a low percentage of patients with osteosarcoma and can be managed successfully by maximum supportive care. MTX clearance can be affected by gender and age.

Concurrent Imatinib Dosing With High-dose Methotrexate Leads to Acute Kidney Injury and Delayed Methotrexate Clearance in Pediatric Patients With Philadelphia Chromosome-positive B-Cell Acute Lymphoblastic Leukemia.

Imatinib, a tyrosine kinase inhibitor has improved survival in pediatric patients with Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia. There are no formal drug interactions listed between methotrexate and tyrosine kinase inhibitors. Four pediatric patients with Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia had delayed methotrexate clearance during their first cycle of high-dose methotrexate while receiving imatinib, resulting in acute kidney injury. For subsequent high-dose methotrexate cycles, imatinib was withheld resulting in decreased acute kidney injury, shorter time to methotrexate clearance, less toxicity, and shorter hospitalizations. For pediatric patients with acute lymphoblastic leukemia receiving imatinib, we recommend escalated supportive care measures including increased hyperhydration and leucovoruin frequency. For patients with toxicities secondary to delayed clearance or need for glucarpidase, we recommend holding imatinib with subsequent high-dose methotrexate courses.

The management of hydatidiform mole using prophylactic chemotherapy and hysterectomy for high-risk patients decreased the incidence of gestational trophoblastic neoplasia in Vietnam: a retrospective observational study.

ABSTRACTThe management of hydatidiform mole (HM) and the incidence of post-molar gestational trophoblastic neoplasia (GTN) in Vietnam has not been reported to date. This study aimed to study the incidence of HM and post-molar GTN and identify factors associated with post-molar GTN at a tertiary hospital in Vietnam. Five hundred and eighty-four patients who were treated for HM at Tu Du Hospital between January and December 2010 were included in this study. The mean age and gestational age at the first evacuation were 28.8 years old and 11.0 weeks, respectively. After the initial evacuation and pathological examination, 87 patients who were older than 40 or did not wish to have children underwent a hysterectomy, while the others underwent second curettage. All 472 patients who had human chorionic gonadotropin (hCG) ≥ 100,000 IU/L before treatment received one cycle of methotrexate with folinic acid as prophylactic chemotherapy. The incidence of HM was 11.1 per 1,000 deliveries; 47 patients (8.0%) developed post-molar GTN. Gestational week, hCG level at one week after the first evacuation, and pathological remnants were significantly associated with the development of post-molar GTN. The results of this study suggest that prophylactic chemotherapy and hysterectomy may be useful for high-risk HM patients to reduce post-molar GTN in settings in which the risk of post-molar GTN and loss to follow-up after HM are greater and hCG measurements and appropriate GTN treatments are unavailable. However, future studies on the long-term outcomes and side effects of prophylactic therapies on HM are required.

Oral sodium bicarbonate protocol for high-dose methotrexate urine alkalinization: A pediatric experience.

Methotrexate (MTX) is a cytotoxic antimetabolite. Intravenous (IV) hydration and urine alkalinization with sodium bicarbonate (NaHCO3) can mitigate nephrotoxicity associated with high-dose MTX (HDMTX, doses ≥500 mg/m2). A shortage of IV NaHCO3 in 2017 prompted Alberta Children's Hospital (ACH) and Stollery Children's Hospital (SCH) to adopt an alternative protocol including oral NaHCO3 and IV hydration with Lactated Ringer's (LR). A retrospective chart review was conducted for ACH and SCH inpatients who received HDMTX between January and December 2017. The primary outcome was the proportion of cycles with delayed HDMTX clearance within the IV and oral cohorts. Secondary outcomes include NaHCO3 administered until clearance, NaHCO3 required to reach pH ≥7, time to reach pH ≥7, incidence of pH <7, time to clearance, and time to discharge. Adverse effects associated with delayed clearance or NaHCO3 administration were also reported. 112 MTX cycles were included, 50 and 62 from the IV and oral cohorts, respectively. Clearance delays beyond protocol expectations occurred in 10 cycles (8.9%), 5 from each cohort (p = 0.72). Differences between cohorts were not statistically significant, except the amounts of NaHCO3 required until clearance (383 vs. 277 mmol/m2, p = 0.005) and to reach pH ≥7 (52 vs. 40 mmol/m2, p = 0.004) were lower in the oral cohort. Incidences of adverse effects were not different. Oral NaHCO3 with LR is a feasible alternative for urine alkalinization. The total dose of NaHCO3 utilized was lower in the oral cohort, with no additional delays in clearance.

Long-term clinically relevant rodent model of methotrexate-induced cognitive impairment.

With the enhanced use of chemotherapy and the advent of increased patient survival rates, there are an increasing number of cancer survivors living with chemotherapy-induced cognitive impairment. A growing number of clinical studies have brought to light the association of agents like methotrexate in generating these neurological sequelae, although mechanisms remain unclear. Here, we use a clinically relevant regimen of several cycles of methotrexate and leucovorin rescue to develop a model of chemotherapy-induced cognitive impairment, and investigate the in vivo long-term (16 mo) impact of high-dose systemic methotrexate on white matter cellular dynamics as assessed by stereology, animal behavior, and diffusion tensor imaging. Our results indicate that at 6 and 16 months post-chemotherapy, methotrexate-treated rats exhibit a significant and permanent decrease in the number of oligodendrocytes and their progenitors in the white matter, in corpus callosum volumes, and myelin basic protein. These findings are associated with mostly delayed deficits in performance on Morris Water Maze and Novel Object Recognition tasks. Diffusion tensor imaging demonstrates significantly decreased fractional anisotropy values in the callosum genu, body, and splenium, as well as previously unassessed areas like the fimbria. Interestingly, these white matter changes are preceded by an earlier, transient decrement in white matter microglia at 3 months, and hippocampal neural progenitors at 3 and 6 months. These results demonstrate a significant negative impact of methotrexate on the oligodendrocyte compartment and white matter, associated with cognitive impairment. The data also support the use of diffusion tensor imaging in monitoring white matter integrity in this context.

Gestational Trophoblastic Neoplasia

Introduction: Gestational trophoblastic neoplasia (GTN) account for less than 1% of cancers of the female reproductive system. Nearly 50% of gestational choriocarcinomas are seen after molar pregnancies. About 25% after abortions or ectopic pregnancy and another 25% after a normal pregnancy. FIGO staging and prognostic scoring index of modified WHO classification is used. Serum β-HCG assay is an important factor in the diagnosis and management of GTN. It is a sensitive tumour marker for GTN and its level is directly related to the number of viable tumour cells. Serial measurement of β-hCG levels is useful for follow-up of women diagnosed with complete or partial mole. An increasing level or plateauing of serum β-hCG is diagnostic of invasive disease which can be invasive mole or choriocarcinoma. Case Report: Patient A-was a 22 year old lady, para1, two year old child which was a normal delivery. She was asymptomatic and reported to the hospital for missed periods. Urine pregnancy test was positive. Ultrasound scan did not find any pregnancy. Beta HCG levels were very high. Then MRI was done which showed no abnormality, other than a bulky uterus. Curettage was done and the report came as trophoblastic tissue seen with possibility of choriocarcinoma. This patient was given 2 cycles of methotrexate with folinic acid after which the patient was lost to follow up. Patient B-was a 27 year old lady, para1, three year old child delivered by caesarean section. She also gave history of two subsequent abortions. She presented with menorrhagia and on examination a cervical polyp was detected. The polyp was resected and sent for histo-pathology and the report suggested choriocarcinoma. Her beta HCG was 30,000. This patient was given three cycles of multi-agent chemotherapy, MAC (Methotrexate, Actinomycin-D and Cyclophosphamide) regime and responded to treatment. Discussion: The main stay of treatment is chemotherapy. Mostly single agent chemotherapy is used methotrexate being the drug of choice. Methotrexate in the dose of 0.4 mg/kg IM or IV daily for 5 days, appears to be the most effective treatment protocol. Another widely used regimen is using folinic acid along with methotrexate. Some of the more commonly used multiagent chemotherapy combinations are – MAC, EMA-CO, EMA-EP, VBP and BEP. Conclusion: GTN can be treated with appropriate chemotherapy and supportive management, after correct staging and scoring of the disease. They are also the most curable of all cancers in women.

Increased Number of High Dose Methotrexate Cycles and the Addition of Rituximab Is Associated with Better Outcomes in a Large Primary CNSL Cohort

Introduction: Primary central nervous system lymphoma (PCNSL) is a rare and aggressive primary brain tumor confined to the brain, eyes, and cerebrospinal fluid. Over the past few decades, prognosis for PCNSL has significantly improved due to the standard use of high dose methotrexate (MTX) containing treatment regimens. However, it remains unclear if the number of MTX doses and the addition of rituximab has an impact on clinical outcomes. The recent HOVON 105/ALLG NHL 24 study questioned the role of rituximab in the first line setting when combined with a MTX based polychemotherapy using only 4 doses of MTX and 6 doses of rituximab. Over the last 30 years, standard of care at Memorial Sloan Kettering Cancer Center (MSKCC) has evolved, allowing the comparison of patients receiving different numbers of MTX doses and those treated with and without rituximab. The purpose of this study was to describe clinical outcomes based on standard of care treatment changes. Methods: This single-center retrospective IRB approved study at MSKCC included patients with immunocompetent PCNSL, age ≥18 years and diagnosed between 1/1983-11/2017. Patients were identified through a departmental database and electronic medical record. The primary objective was to describe overall survival (OS) based on common prognostic markers such as age, KPS, MSKCC prognostic score class (RPA I- III), use of rituximab, and number of methotrexate cycles. Overall survival was calculated from the date of diagnosis to death or last follow-up using Kaplan-Meier methodology. When examining effect of MTX on OS, OS was calculated from date of last MTX cycle until death or last follow-up. Univariable and multivariable analysis for prognostic factors were analyzed using Cox proportional hazards regression. Results: Five hundred and forty-six patients with newly diagnosed PCNSL were identified. Median age at diagnosis was 62 (range 19 to 90), median KPS was 70 (range 10 to 100), and 282 (52%) were men. In total, 472 patients (86.4%) received high dose MTX. Of 460 with known number of MTX cycles, 95 (20.7%) received 1-4 cycles and 365 (79.3%) received ≥5 cycles (5 cycles: 189, 41.1%, 6 cycles: 24, 5.2%, 7 cycles: 74, 16.1%, 8+ cycles: 78, 17%). Rituximab was given to 231 (42.3%). Three hundred and ten (56.8%) patients, treated before 2006, had been reported previously (historic cohort) and 236 (43.2%) served as contemporary cohort. Median OS of the entire population was 4.7 years (95% CI: 3.8-5.7); 3.3 years (95% CI: 2.8-4.1) in the historic and 8.1 years (95% CI: 6.6-no upper limit) in the contemporary cohort. Five-year OS was 40.3% (95% CI: 35.1-46.2) for the historical cohort and 61.8% (95% CI: 55.0-69.5) for the contemporary cohort. Median OS in the contemporary cohort improved in all RPA classes in comparison to patients treated before 2006 (RPA I: not yet reached vs 9.2 years; RPA II: 7.6 years vs 3.5 years; RPA III 2.8 years vs 1.0 year) (Fig. 1). For the historical cohort compared to the contemporary cohort, five-year OS changed from 62.8% to 91.0% in RPA I, 42.0% to 63.0% in RPA II, and 16.3% to 36.9% in RPA III. Patients receiving ≥ 6 cycles of MTX had a better clinical outcome (median OS from last MTX cycle: 7.8 years versus 4.3 years; HR 0.68 (95% CI (0.51 - 0.91), p=0.0085) on multivariable analysis adjusted for age, KPS, sex, RPA classes Additionally, the stratification of rituximab further elucidated the association between MTX cycles and OS, such that in patients receiving rituximab, those treated with ≥ 6 cycles of MTX experienced longer median OS compared to patients receiving &amp;lt; 6 cycles of MTX (13.0 years vs 9.4 years, p=0.001). Furthermore, in patients receiving ≥ 6 cycles of MTX, there was a survival benefit seen in patients who received rituximab compared to those who did not receive rituximab (13.02 years vs 1.61 years, p&amp;lt;000.1) (Fig.2). Conclusions: Overall survival for newly diagnosed PCNSL has improved significantly over the last few decades regardless of age, KPS, RPA class. Patients seem to benefit with the addition of rituximab and when receiving 6 or more cycles of MTX. Disclosures Grommes: BTG: Consultancy; Kite: Consultancy; Squipps: Speakers Bureau.

A Multicenter Phase I Study Combining Venetoclax with Mini-Hyper-CVD in Older Adults with Untreated and Relapsed/Refractory Acute Lymphoblastic Leukemia

A Multicenter Phase I Study Combining Venetoclax with Mini-Hyper-CVD in Older Adults with Untreated and Relapsed/Refractory Acute Lymphoblastic Leukemia