Hybrid Email and Outpatient Clinics to Optimize Maintenance Therapy in Acute Lymphoblastic Leukemia.

Acute lymphoblastic leukemia treatment includes an outpatient (OP)-based 2-year maintenance therapy (MT). Over an 8-year period, patients were transited from only OP to a hybrid e-clinic/OP-clinic model. Electronic and patient-held medical records of acute lymphoblastic leukemia patients 1 to 18 years old during MT were used to analyze demographics, drug doses, treatment response and cost. A survey evaluated family satisfaction with the hybrid service. Four hundred and seventy-eight children, all with at least 1 year of MT from March 13, 2014 to March 24, 2022 were grouped into 4 treatment eras, representing the transition from all OP (era 1) to the current hybrid MT practice (era 4). Cohort demographics were similar across all eras. With transition to era 4, OP visits decreased to a third (16 to 18/48 visits). Practice optimization in era 2 resulted in higher MT dose intensity in subsequent eras (era 1: median 82% [interquartile range, 63 to 97]; era 2: 93% [73 to 108]; era 3: 88% [68 to 106]; era 4: 90% [74 to 114], P <0·0001), with no differences in absolute neutrophil count or neutropenia-related toxicity ( P =0.8). The hybrid service reduced MT expenses by ~50% and families (133/156, 85%) reported being very satisfied. Our experience indicates that a hybrid model is feasible, effective and less burdensome for patients and families.

A Bayesian quantile joint modeling of multivariate longitudinal and time-to-event data.

Linear mixed models are traditionally used for jointly modeling (multivariate) longitudinal outcomes and event-time(s). However, when the outcomes are non-Gaussian a quantile regression model is more appropriate. In addition, in the presence of some time-varying covariates, it might be of interest to see how the effects of different covariates vary from one quantile level (of outcomes) to the other, and consequently how the event-time changes across different quantiles. For such analyses linear quantile mixed models can be used, and an efficient computational algorithm can be developed. We analyze a dataset from the Acute Lymphocytic Leukemia (ALL) maintenance study conducted by Tata Medical Center, Kolkata. In this study, the patients suffering from ALL were treated with two standard drugs (6MP and MTx) for the first two years, and three biomarkers (e.g. lymphocyte count, neutrophil count and platelet count) were longitudinally measured. After treatment the patients were followed nearly for the next three years, and the relapse-time (if any) for each patient was recorded. For this dataset we develop a Bayesian quantile joint model for the three longitudinal biomarkers and time-to-relapse. We consider an Asymmetric Laplace Distribution (ALD) for each outcome, and exploit the mixture representation of the ALD for developing a Gibbs sampler algorithm to estimate the regression coefficients. Our proposed model allows different quantile levels for different biomarkers, but still simultaneously estimates the regression coefficients corresponding to a particular quantile combination. We infer that a higher lymphocyte count accelerates the chance of a relapse while a higher neutrophil count and a higher platelet count (jointly) reduce it. Also, we infer that across (almost) all quantiles 6MP reduces the lymphocyte count, while MTx increases the neutrophil count. Simulation studies are performed to assess the effectiveness of the proposed approach.

Activity and toxicity of intramuscular 1000 iu/m2 polyethylene glycol-E. coli L-asparaginase in the UKALL 2003 and UKALL 2011 clinical trials.

In successive UK clinical trials (UKALL 2003, UKALL 2011) for paediatric acute lymphoblastic leukaemia (ALL), polyethylene glycol-conjugated E. coli L-asparaginase (PEG-EcASNase) 1000 iu/m2 was administered intramuscularly with risk-stratified treatment. In induction, patients received two PEG-EcASNase doses, 14 days apart. Post-induction, non-high-risk patients (Regimens A, B) received 1-2 doses in delayed intensification (DI) while high-risk Regimen C patients received 6-10 PEG-EcASNase doses, including two in DI. Trial substudies monitored asparaginase (ASNase) activity, ASNase-related toxicity and ASNase-associated antibodies (total, 1112 patients). Median (interquartile range) trough plasma ASNase activity (14 ± 2 days post dose) following first and second induction doses and first DI dose was respectively 217 iu/l (144-307 iu/l), 265 iu/l (165-401 iu/l) and 292 iu/l (194-386 iu/l); 15% (138/910) samples showed subthreshold ASNase activity (<100 iu/l) at any trough time point. Older age was associated with lower (regression coefficient -9.5; p < 0.0001) and DI time point with higher ASNase activity (regression coefficient 29.9; p < 0.0001). Clinical hypersensitivity was observed in 3.8% (UKALL 2003) and 6% (UKALL 2011) of patients, and in 90% or more in Regimen C. A 7% (10/149) silent inactivation rate was observed in UKALL 2003. PEG-EcASNase schedule in UKALL paediatric trials is associated with low toxicity but wide interpatient variability. Therapeutic drug monitoring potentially permits optimisation through individualised asparaginase dosing.

Unsatisfactory quality of E. coli asparaginase biogenerics in India: Implications for clinical outcomes in acute lymphoblastic leukaemia.

BACKGROUND: The biotherapeutic asparaginase is a cornerstone of therapy in acute lymphoblastic leukaemia (ALL). With limited access to the original native Escherichia coli-derived asparaginase (EcASNase), a variety of EcASNase biogenerics are used in low-middle-income countries (LMICs). The variable quality of these biogenerics potentially influences clinical outcomes. PROCEDURE: Seven biogeneric EcASNases (P1-P7) marketed widely in India were evaluated, with P2 as an exemplar for in vivo monitoring. Therapeutic activity of P2 (10,000 IU/m2 /dose, intramuscular, every 72 hours) was monitored during induction therapy, and drug-related toxicities recorded. Molecular identity, purity and in vitro drug activity of seven biogenerics were characterised using multimodal analyses, and findings compared with reference EcASNase (R). RESULTS: In patients (N = 62) receiving P2, subtherapeutic asparaginase activity (<100 U/L) was observed in 66% (46/70) of trough timepoints (72 hours postdose) during induction. Twelve patients (19%), 11 with high-risk ALL, developed hypersensitivity. Isoforms of EcASNase were identified in all seven biogenerics. All generic products contained impurities with batch-to-batch variability. These included high levels of protein aggregates and host cell protein contamination. In vitro assays of EcASNase activity and leukaemia cell line cytotoxicity were not discriminatory. CONCLUSIONS: Our findings confirm widespread concerns over the unsatisfactory quality and therapeutic activity of native EcASNase biogenerics marketed in LMICs. Appropriate use of these products requires monitored studies to identify clinical suitability and determine appropriate dosing and schedule. For large parts of the world, assured access to high-quality asparaginases remains an unmet therapeutic need.

Efficacy and safety of a bortezomib and reduced-intensity cytarabine-based protocol, TMC ALLR1, for relapsed childhood ALL in India.

The feasibility of bortezomib (BZB) in induction and reduced cytarabine doses in intensification was evaluated in children with relapsed acute lymphoblastic leukaemia (rALL) at a single centre in India. Of 55 children with rALL, 23 received supportive care and 7 refused treatment, with a median survival of 2 (interquartile range 1-6) months. Twenty-two (88%) of 25 children who were treated achieved second remission and 9 (69%) of 13 had end-of-induction minimal residual disease of <10-4 . The lower cytarabine dose was associated with decreased hospitalisation. One-year event-free and overall survival for the treated group was 74·7% (95% confidence interval 52-88) and 79·6% (58-91) respectively.

A triple-probe FISH screening strategy for risk-stratified therapy of acute lymphoblastic leukaemia in low-resource settings.

Karyotyping along with a 3-probe fluorescence in situ hybridization (FISH) strategy was used to risk stratify therapy in 303 children with B-cell precursor acute lymphoblastic leukaemia. Of the 166 patients risk stratified, karyotype identified 91 (55%). FISH identified all karyotypes accurately, with the exception of hypodiploidy, and risk stratified an additional 75 patients. The frequency of ETV6-RUNX1 is lower and high hyperdiploidy, higher than reported in the west. An adapted 3-probe FISH strategy identified two patients with ETV6-ABL1 fusion who received imatinib. In limited-resource settings, a 3-probe FISH approach provides a practical approach for risk-stratified therapy in childhood ALL.

Targeting the 5T4 oncofetal glycoprotein with an antibody drug conjugate (A1mcMMAF) improves survival in patient-derived xenograft models of acute lymphoblastic leukemia.

Outcome in childhood acute lymphoblastic leukemia is prognosticated from levels of minimal residual disease after remission induction therapy. Higher levels of minimal residual disease are associated with inferior results even with intensification of therapy, thus suggesting that identification and targeting of minimal residual disease cells could be a therapeutic strategy. Here we identify high expression of 5T4 in subclonal populations of patient-derived xenografts from patients with high, post-induction levels of minimal residual disease. 5T4-positive cells showed preferential ability to overcome the NOD-scidIL2Rγnull mouse xenograft barrier, migrated in vitro on a CXCL12 gradient, preferentially localized to bone marrow in vivo and displayed the ability to reconstitute the original clonal composition on limited dilution engraftment. Treatment with A1mcMMAF (a 5T4-antibody drug conjugate) significantly improved survival without overt toxicity in mice engrafted with a 5T4-positive acute lymphoblastic leukemia cell line. Mice engrafted with 5T4-positive patient-derived xenograft cells were treated with combination chemotherapy or dexamethasone alone and then given A1mcMMAF in the minimal residual disease setting. Combination chemotherapy was toxic to NOD-scidIL2Rγnull mice. While dexamethasone or A1mcMMAF alone improved outcomes, the sequential administration of dexamethasone and A1mcMMAF significantly improved survival (P=0.0006) over either monotherapy. These data show that specifically targeting minimal residual disease cells improved outcomes and support further investigation of A1mcMMAF in patients with high-risk B-cell precursor acute lymphoblastic leukemia identified by 5T4 expression at diagnosis.

Whole-genome sequencing analysis of phenotypic heterogeneity and anticipation in Li-Fraumeni cancer predisposition syndrome.

The Li-Fraumeni syndrome (LFS) and its variant form (LFL) is a familial predisposition to multiple forms of childhood, adolescent, and adult cancers associated with germ-line mutation in the TP53 tumor suppressor gene. Individual disparities in tumor patterns are compounded by acceleration of cancer onset with successive generations. It has been suggested that this apparent anticipation pattern may result from germ-line genomic instability in TP53 mutation carriers, causing increased DNA copy-number variations (CNVs) with successive generations. To address the genetic basis of phenotypic disparities of LFS/LFL, we performed whole-genome sequencing (WGS) of 13 subjects from two generations of an LFS kindred. Neither de novo CNV nor significant difference in total CNV was detected in relation with successive generations or with age at cancer onset. These observations were consistent with an experimental mouse model system showing that trp53 deficiency in the germ line of father or mother did not increase CNV occurrence in the offspring. On the other hand, individual records on 1,771 TP53 mutation carriers from 294 pedigrees were compiled to assess genetic anticipation patterns (International Agency for Research on Cancer TP53 database). No strictly defined anticipation pattern was observed. Rather, in multigeneration families, cancer onset was delayed in older compared with recent generations. These observations support an alternative model for apparent anticipation in which rare variants from noncarrier parents may attenuate constitutive resistance to tumorigenesis in the offspring of TP53 mutation carriers with late cancer onset.

Pediatric Vaginal Yolk Sac Tumor: Reappraisal of Treatment Strategy in a Rare Tumor at a Unique Location.

Review of the management of 6 young girls with vaginal yolk sac tumor over 25 years showed that the α-fetoprotein levels normalized in 5/6 within 4 cycles of primary cisplatin, bleomycin, etoposide (PEB)/carboplatin, etoposide, bleomycin (JEB)/cisplatin, vinblastine, bleomycin (PVB) chemotherapy. Radioimaging revealed residual tissue but viable tumor was found in only 1 of 2 biopsied. Resection/biopsy is necessary to avoid giving additional primary chemotherapy or to identify patients who need different treatment. If markers do not decay appropriately, PEB/JEB/PVB chemotherapy should not be continued. Taxol-containing salvage chemotherapy regimens, adjuvant modern radiotherapeutic treatment, and fertility-saving curative surgery should then be considered. Despite having mostly advanced disease, 5/6 patients were cured, 2 with chemotherapy alone.

Relapsed Acute Lymphoblastic Leukemia.

Outcomes for children with acute lymphoblastic leukemia (ALL) have improved worldwide to >85%. For those who relapse, outcomes have remained static at ~50% making relapsed acute lymphoblastic leukemia one of the leading causes of death in childhood cancers. Those relapsing within 18 mo in the bone marrow have a particularly dismal outcome. The mainstay of treatment is chemotherapy, local radiotherapy with or without hematopoietic stem cell transplantation (HSCT). Improved biological understanding of mechanisms of relapse and drug resistance, use of innovative strategies to identify the most effective and least toxic treatment regimens and global partnerships are needed to improve outcomes in these patients. Over the last decade, new therapeutic options and strategies have been developed for relapsed ALL including immunotherapies and cellular therapies. It is imperative to understand how and when to use these newer approaches in relapsed ALL. Increasingly, integrated precision oncology strategies are being used to individualize treatment of patients with relapsed ALL, especially in patients with poor response disease.

Maintenance Treatment in Acute Lymphoblastic Leukemia: A Clinical Primer.

Cure rates in pediatric acute lymphoblastic leukemia (ALL) currently approach 90% in the developed world. Treatment involves 6-8 mo of intensive multi-drug chemotherapy followed by 24 mo of maintenance treatment (ALL-MT). The cornerstone of ALL-MT is the daily administration of oral 6-mercaptopurine (6MP), a purine analogue. 6MP is combined with weekly oral methotrexate (MTX), an antifolate drug, to augment therapeutic activity. Some protocols include additional chemotherapy drugs (such as vincristine and corticosteroids) during MT. The objective of ALL-MT is to ensure uninterrupted treatment at the highest tolerated doses of 6MP and MTX. This requires periodic adjustments of 6MP and MTX doses throughout treatment. Tolerance is determined through regular clinical assessments and careful monitoring of blood counts. Tolerated drug doses vary widely among patients, influenced by genetic and non-genetic factors, and require individualized dosing. Suboptimal treatment intensity in ALL-MT is associated with inferior outcomes and results from failure to treat at highest tolerated drug doses and/or interruptions in treatment due to non-adherence or toxicity. Management of MT thus requires close supervision to ensure treatment adherence, periodic drug dose modifications, and treatment to tolerance, while minimizing treatment interruptions due to toxicity. The review highlights these challenges and discusses approaches and strategies for the management of MT, focusing on the Indian context.

Rational engineering of L-asparaginase reveals importance of dual activity for cancer cell toxicity.

Using proteins in a therapeutic context often requires engineering to modify functionality and enhance efficacy. We have previously reported that the therapeutic antileukemic protein macromolecule Escherichia coli L-asparaginase is degraded by leukemic lysosomal cysteine proteases. In the present study, we successfully engineered L-asparaginase to resist proteolytic cleavage and at the same time improve activity. We employed a novel combination of mutant sampling using a genetic algorithm in tandem with flexibility studies using molecular dynamics to investigate the impact of lid-loop and mutations on drug activity. Applying these methods, we successfully predicted the more active L-asparaginase mutants N24T and N24A. For the latter, a unique hydrogen bond network contributes to higher activity. Furthermore, interface mutations controlling secondary glutaminase activity demonstrated the importance of this enzymatic activity for drug cytotoxicity. All selected mutants were expressed, purified, and tested for activity and for their ability to form the active tetrameric form. By introducing the N24A and N24A R195S mutations to the drug L-asparaginase, we are a step closer to individualized drug design.

RAC2, AEP, and ICAM1 expression are associated with CNS disease in a mouse model of pre-B childhood acute lymphoblastic leukemia.

We developed a murine model of CNS disease to obtain a better understanding of the pathogenesis of CNS involvement in pre-B-cell acute lymphoblastic leukemia (ALL). Semiquantitative proteomic discovery-based approaches identified unique expression of asparaginyl endopeptidase (AEP), intercellular adhesion molecule 1 (ICAM1), and ras-related C3 botulinum toxin substrate 2 (RAC2), among others, in an invasive pre-B-cell line that produced CNS leukemia in NOD-SCID mice. Targeting RAC2 significantly inhibited in vitro invasion and delayed disease onset in mice. Induced expression of RAC2 in cell lines with low/absent expression of AEP and ICAM1 did not result in an invasive phenotype or murine CNS disease. Flow cytometric analysis identified an enriched population of blast cells expressing ICAM1/lymphocyte function associated antigen-1 (LFA-1)/CD70 in the CD10(+)/CD19(+) fraction of bone marrow aspirates obtained from relapsed compared with normal controls and those with primary disease. CD10(+)/CD19(+) fractions obtained from relapsed patients also express RAC2 and give rise to CNS disease in mice. Our data suggest that combinations of processes are involved in the pathogenesis of CNS disease in pre-B-cell ALL, support a model in which CNS disease occurs as a result of external invasion, and suggest that targeting the processes of adhesion and invasion unique to pre-B cells may prevent recurrences within the CNS.

Comparative treatment costs of risk-stratified therapy for childhood acute lymphoblastic leukemia in India.

BACKGROUND: To evaluate the treatment cost and cost effectiveness of a risk-stratified therapy to treat pediatric acute lymphoblastic leukemia (ALL) in India. METHODS: The cost of total treatment duration was calculated for a retrospective cohort of ALL children treated at a tertiary care facility. Children were risk stratified into standard (SR), intermediate (IR) and high (HR) for B-cell precursor ALL, and T-ALL. Cost of therapy was obtained from the hospital electronic billing systems and details of outpatient (OP) and inpatient (IP) from electronic medical records. Cost effectiveness was calculated in disability-adjusted life years. RESULTS: One hundred and forty five patients, SR (50), IR (36), HR (39), and T-ALL (20) were analyzed. Median cost of the entire treatment for SR, IR, HR, and T-ALL was found to be $3900, $5500, $7400, and $8700, respectively, with chemotherapy contributing to 25%-35% of total cost. Out-patient costs were significantly lower for SR (p < 0.0001). OP costs were higher than in-patient costs for SR and IR, while in-patient costs were higher in T-ALL. Costs for non-therapy admissions were significantly higher in HR and T-ALL (p < 0.0001), representing over 50% of costs of in-patient therapy. HR and T-ALL also had longer durations of non-therapy admissions. Based on WHO-CHOICE guidelines, the risk-stratified approach was very cost effective for all categories of patients. CONCLUSIONS: Risk-stratified approach to treat childhood ALL is very cost-effective for all categories in our setting. The cost for SR and IR patients is significantly reduced through decreased IP admissions for both, chemotherapy and non-chemotherapy reasons.

Characteristics and outcomes of gallbladder cancer patients at the Tata Medical Center, Kolkata 2017-2019.

BACKGROUND: The north and north-eastern regions of India have among the highest incidence of gallbladder cancer (GBC) in the world. We report the clinicopathological charateristics and outcome of GBC patients in India. METHODS: Electronic medical records of patients diagnosed with GBC at Tata Medical Center, Kolkata between 2017 and 2019 were analyzed. RESULTS: There were 698 cases of confirmed GBC with a median age of 58 (IQR: 50-65) years and female:male ratio of 1.96. At presentation, 91% (496/544) had stage III/IV disease and 30% (189/640) had incidental GBC. The 2-year overall survival (OS) was 100% (95% CI: 100-100); 61% (95% CI: 45-83); 30% (95% CI: 21-43); and 9% (95% CI: 6-13) for stages I-IV, respectively (p = <0.0001).   For all patients, the 2-year OS in patients who had a radical cholecystectomy followed by adjuvant therapy (N = 36) was 50% (95% CI: 39-64), compared to 29% (95% CI: 22-38) for those who had a simple cholecystectomy and/or chemotherapy (N = 265) and 9% (95% CI: 6-14) in patients who were palliated (N = 107) (p = <0.0001). CONCLUSION: The combined surgical/chemotherapy approach for patients with stage II GBC showed the best outcomes. Early detection of GBC remains problematic with the majority of patients presenting with stage III-IV and who have a median survival of 9.1 months. Our data suggests that the tumor is chemoresponsive and multi-center collaborative clinical trials to identify alternative therapies are urgently required.

A Pilot Study to Determine the Utility of Automated Tissue Dissociator for Flowcytometry Based Evaluation of Hematolymphoid Tumor Tissue Biopsies.

Routine diagnostic biopsy tissue processing, conventional histology/immunohistochemistry (IHC) method is a multi-step and time consuming practice. With the advanced tissue dissociation protocols and panel designing, flow cytometric immunophenotyping (FCI) can be performed on diagnostic hematolymphoid tissue samples using single cell suspensions that economize steps and the time taken. Diagnostic tissue samples from lymph node, mediastinal mass, testicular biopsies and similar sites were dissociated using gentle MACS Octo-dissociator and FCI was performed thereafter. Oral tissue biopsy samples were also processed as a validation set for the protocol. 21 prospective tissue biopsy samples with suspected involvement by a known hematolymphoid neoplasm were processed and evaluated. These included B lymphoblastic lymphoma (n = 12), T lymphoblastic lymphomas (n = 3), Burkitts lymphoma (n = 3) and one case each of granulocytic sarcoma, Hodgkin lymphoma and granulomatous disease. Tissue FCI and IHC were found concordant with identified profile FCI obtained from blood/bone marrow analyses. FCI can produce a highly sensitive and reliable report, within hours, by processing fresh tumor tissue samples from suspected hematolymphoid malignancies. This method can be considered as an effective adjunct to IHC and can be applicable in routine clinical diagnostics, especially in cases that needs quick diagnosis and immediate clinical treatment.