Utility of CD36 as a novel addition to the immunophenotypic signature of RAM-phenotype acute myeloid leukemia and study of its clinicopathological characteristics

INTRODUCTION

In 2016, Children Oncology Group (COG) described a new high-risk subtype of acute myeloid leukemia (AML) with a distinct immunophenotypic-signature, RAM-phenotype (RAM-AML). Data on clinical and laboratory features of RAM-AML are still limited to COG report only. Herein, we report the clinicopathological characteristics and detailed immunophenotypic features of RAM-AML patients. In COG report, 38% of RAM-AML belonged to acute megakaryoblastic leukemia (AMKL)-subtype. Hence, we further compared the immunophenotypic features RAM-AML with non-RAM-AMKL diagnosed during the same study period.

METHODS

We included RAM-AML and non-RAM AMKL patients diagnosed between January 2017 and December 2019. We studied their morphological, cytochemical, immunophenotyping, cytogenetic, and molecular characteristics. Mean fluorescent intensity (MFI) and expression-pattern of immunophenotypic markers of RAM-AML were compared with non-RAM AMKLs patients.

RESULTS

We identified 11 RAM-AML (1%) and 21 non-RAM AMKL (1.9%) patients in 1102 pediatric-AML patients. Seven of 11 (63.64%) patients belonged to FAB-M7-subtype. CD56, CD117, and CD33 demonstrated overexpression, whereas CD45 and CD38 showed under-expression in RAM-AML patients. CD36 was consistently negative in RAM-AML, whereas moderate-bright positive in non-RAM AMKLs patients (p < 0.0001). On principle component analysis, addition of CD36 enhanced the visual-separation between RAM-AML and non-RAM AMKL clusters. Cytogenetic and molecular studies did not show any recurrent abnormality; however, RNA-sequencing study revealed CBFA2T3-GLIS2-fusion in three of seven (42.8%) RAM-AML patients.

CONCLUSION

We report the clinicopathological characteristics and the detailed immunophenotypic profile in the world's second series of RAM-AML patients. We further report a novel finding of CD36-negative expression as an additional parameter to the multidimensional immunophenotypic signature of this entity.

Machine learning derived genomics driven prognostication for acute myeloid leukemia with RUNX1-RUNX1T1

Panel based next generation sequencing was performed on a discovery cohort of AML with RUNX1-RUNX1T1. Supervised machine learning identified NRAS mutation and absence of mutations in ASXL2, RAD21, KIT and FLT3 genes as well as a low mutation to be associated with favorable outcome. Based on this data patients were classified into favorable and poor genetic risk classes. Patients classified as poor genetic risk had a significantly lower overall survival (OS) and relapse free survival (RFS). We could validate these findings independently on a validation cohort (n=61). Patients in the poor genetic risk group were more likely to harbor measurable residual disease. Poor genetic risk emerged as an independent risk factor predictive of inferior outcome. Using an unbiased computational approach based we provide evidence for gene panel-based testing in AML with RUNX1-RUNX1T1 and a framework for integration of genomic markers toward clinical decision making in this heterogeneous disease entity.

Assessment of tumor Epstein-Barr Virus status and its impact on outcomes in intermediate and high-risk childhood classic Hodgkin Lymphoma treated at a tertiary cancer center in India

Indian studies on EBV in childhood classic Hodgkin Lymphoma (cHL) have mainly analyzed the epidemiology of EBV-positive [EBV(+)HL] or negative HL [EBV(-)HL], with limited data on outcomes. We studied a large cohort of children with intermediate and high-Risk cHL for tumor EBV status and its impact on outcomes retrospectively. Of evaluable 189 patients, 84.7% had EBV(+)HL. Positive status was significantly associated with age ≤ 10 years (p < .001), males (p = .015), non-Nodular Sclerosis (NS) histology (p = .004) and inversely with bulky-mediastinal disease (p < .001). At a median follow-up of 29-months (range1-75), 3-year Event-Free Survival (EFS) for EBV(+)HL and EBV(-)HL was 93.6%(95%CI:89.8%-97.5%), 81.1%(95%CI:67.2%-97.9%), (p = .048) and Overall Survival (OS) was 94.9%(95%CI:91.6%-98.4%), 84.6%(95%CI:71.5%-100%), (p = .075) respectively. Three-year EFS was better in males (HR-0.267,95%CI:0.078-0.916, p = .036) in EBV(+)HL and in patients with serum-albumin > 3g/dL (HR-0.117,95%CI:0.019-0.705, p = .019) in EBV(-)HL. EBV is associated with most of intermediate and high-risk childhood cHL, occurs in younger male patients with non-NS histology, with reduced incidence of bulky-mediastinal disease and favorable survival in childhood cHL.

Investigating the clinical, hematological and cytogenetic profile of endoreduplicated hypodiploids in BCP-ALL

Ploidy, besides known translocations in lymphoblasts, is a strong predictor of prognosis in B- cell progenitor acute lymphoblastic leukemia (BCP-ALL). While hyperdiploidy with >50 chromosomes shows a favourable outcome, hypodiploidy with <45 chromosomes have a dismal clinical outcome. However, there exists a small subset where both the hypodiploid and hyperdiploid clones are apparent either by cytogenetics or flow cytometry and are defined partially masked hypodiploids or mosaics based on the percentage of clonal population. These patients are essentially hypodiploids, and show the hyperdiploid clone as a consequence of endoreduplication of the primary hypodiploid clone- A phenomenon of successive replication of genome without mitosis (cytokinesis) resulting in increased ploidy. In the current study, we present the complete clinical, hematological and cytogenetic profile of 11 such newly diagnosed mosaics or partially masked hypodiploid BCP-ALL cases.

High Response Rates and Promising Outcomes of Patients with Relapsed Ewing Sarcoma, Especially in Adolescents and Young Adults Treated on a Novel Hybrid Salvage Chemotherapy Regimen

Purpose: About 30%-35% of nonmetastatic and 60%-80% of metastatic Ewing Sarcoma (ES) will relapse post-treatment and outcomes after relapse continue to be poor over last several decades. Prognostic factors affecting survival after relapse of ES are also not robustly known. We present outcomes using a novel hybrid salvage protocol of four active chemotherapeutic agents in our cohort of patients after relapse of ES. Methods: This is a retrospective analysis of all consecutive relapsed ES patients treated with curative intent over 4 years (January 2012 to December 2015). All received 12-cycles of hybrid chemotherapy regimen with surgery/radiotherapy done after first 4 cycles. Event-free survival (EFS)/overall survival (OS) estimates were analyzed by Kaplan-Meier product-limit estimator. Cox regression analysis was performed to identify prognostic factors predicting outcome in relapsed ES. Results: Salvage regimen was given to 53/108 relapsed ES patients with the rest having opted for palliation upfront. Median age of the treated patients was 19 years (range: 4-40); male:female ratio was 2.7:1. Median time to first relapse was 18.8 months (range: 2.2-91). While 41/53 patients (77%) completed salvage therapy, 6 (11.3%) progressed and 6 (11.3%) abandoned treatment. Median follow-up of the study cohort is 31 months (range: 4-81). Of the analyzable cohort (n = 47), 30 (64%) had a second relapse or progression on salvage treatment. At last follow-up, 31 patients had died (including one due to toxicity and rest due to disease) and 16 patients were alive (14 with no active disease and 2 with disease). The 4-year EFS and OS are 28% and 37%, respectively, for the entire cohort. While adolescents and young adult patients (AYA) had a better survival (p-0.041), relapsed ES patients with shorter disease-free interval (DFI) (<24 months) had a poorer survival (p-0.004). The type of relapse (local or metastatic or combined) after primary treatment did not affect outcome after salvage therapy. Conclusions: We have used a novel hybrid chemotherapy protocol using four active agents in relapsed ES, which is well tolerated and shows promising results. Older age (≥15 years) and longer DFI (>24 months) portend better survival post-relapse. In our cohort of relapsed ES, AYAs fared better than others and type of relapse after primary treatment did not affect outcome after salvage therapy.

Metronomic Chemotherapy for Children in Low- and Middle-Income Countries: Survey of Current Practices and Opinions of Pediatric Oncologists

PURPOSE

Low- and middle-income countries (LMICs) experience the burden of 80% of new childhood cancer cases worldwide, with cure rates as low as 10% in some countries. Metronomics combines frequent administrations of low-dose chemotherapy with drug repurposing, which consists of using already-approved drugs for new medical applications. With wide availability, limited costs, and little infrastructure needs, metronomics can be part of constraint-adapted regimens in these resource-limited settings—with the understanding that metronomics shall not be a substitute for standard treatments when available and doable. Our study aims to describe the experience, practices, opinions, and needs in metronomics of physicians working in LMICs.

METHODS

An online questionnaire was sent to more than 1,200 physicians in pediatric oncology networks in LMICs. Items included the type of center, physician’s demographics, experience in pediatric oncology, and experience with current knowledge of metronomics. Opinions and perspectives were explored using multiple-answer and open questions.

RESULTS

Of physicians, 17% responded. Of respondents, 54.9% declared that they had already used a metronomic regimen. The most frequently cited repositioned drugs were celecoxib (44%) followed by propranolol and valproic acid (17%). Respondents highlighted the advantages of outpatient use (20%) and expected low toxicity (24%). In considering the drawbacks of metronomics, 47% of responses highlighted the lack of scientific evidence or guidelines, 33% the availability or affordability of drugs, and 18% the problem of acceptance or compliance. Of physicians, 79% believed that use of metronomics will spread in LMICs in the near future and 98% of them were willing to participate in international metronomic protocols or registries.

CONCLUSION

Metronomics is already used in LMICs and is a potential answer to unmet needs in pediatric oncology. There is room for improvement in the availability of drugs and a necessity to develop collaborative protocols and research to generate level A evidence.

Post-induction Measurable Residual Disease Using Multicolor Flow Cytometry Is Strongly Predictive of Inferior Clinical Outcome in the Real-Life Management of Childhood T-Cell Acute Lymphoblastic Leukemia: A Study of 256 Patients

Background: Measurable/minimal residual disease (MRD) status is suggested as a powerful indicator of clinical-outcome in T-cell lymphoblastic leukemia/lymphoma (T-ALL). Contrary to B-cell ALL, reports on T-ALL MRD are limited and mostly based on molecular methods, mainly from developed countries. Multicolor flow cytometry (MFC)-based T-ALL studies are very few. Clinically relevant cut-off levels and ideal time-point for MRD assessment are still inconclusive. In view of lack of T-ALL MRD data from the developing world, we evaluated the prognostic value of MFC-based post-induction (PI)-MRD assessment in T-ALL in the context of standard practice. Methods: We included 256 childhood-T-ALL patients (age < 15 years) treated with a modified-MCP841 protocol, which uses high-dose cytarabine during consolidation, as a part of standard hospital practice. MRD was studied using 10-color 11-antibody MFC with any level of detectable disease being considered positive. Post-induction (PI)-MRD was available in all patients, and post-consolidation (PC) MRD was available mostly in PI-MRD-positive patients (n = 88). Results: Three years cumulative-incidence-of-relapse (3years-CIR) in PI-MRD-positive patients was inferior to negative patients (46.3% vs. 18.4%). The median relapse-free-survival (RFS), event-free-survival (EFS) and overall-survival (OS) with hazard ratio (HR) of PI-MRD-positive patients were 21.4 months vs not reached (p < 0.0001, HR-4.7), 21.6 months vs. not-reached (p = 0.0003, HR-2.01) and 37.3 months vs. not reached (p = 0.026, HR-1.64) respectively. RFS, EFS and OS of patients with PI-MRD<0.01% (n = 17) were as inferior as PI-MRD ≥ 0.01% in comparison with MRD-negative patients with HR of 4.7 (p < 0.0001), 2.45 (p = 0.0003), and 2.5 (p = 0.029), respectively. Three-years-CIR of patients with hyperleukocytosis (≥100 × 109/L) was also higher (50.5 vs. 27.6%) with inferior RFS, EFS, and OS. Among PI-MRD-positive patients, 3years-CIR, RFS, EFS, and OS of PC-MRD-positive were also inferior to that of negative patients. On multivariate analysis any-level detectable PI-MRD and hyperleukocytosis remained independently associated with inferior RFS, EFS, and OS. A combination of PI-MRD-positive status and hyperleukocytosis identified the patients with the worst clinical outcomes. Conclusion: Detectable PI-MRD using MFC was found to be the strong predictive factor of inferior clinical outcome in T-ALL patients. The combination of PI-MRD status and hyperleukocytosis provides the most influential tool for the management of T-ALL in resource constrained settings from developing world.

Sustainable care for children with cancer: a Lancet Oncology Commission

We estimate that there will be 13·7 million new cases of childhood cancer globally between 2020 and 2050. At current levels of health system performance (including access and referral), 6·1 million (44·9%) of these children will be undiagnosed. Between 2020 and 2050, 11·1 million children will die from cancer if no additional investments are made to improve access to health-care services or childhood cancer treatment. Of this total, 9·3 million children (84·1%) will be in low-income and lower-middle-income countries. This burden could be vastly reduced with new funding to scale up cost-effective interventions. Simultaneous comprehensive scale-up of interventions could avert 6·2 million deaths in children with cancer in this period, more than half (56·1%) of the total number of deaths otherwise projected. Taking excess mortality risk into consideration, this reduction in the number of deaths is projected to produce a gain of 318 million life-years. In addition, the global lifetime productivity gains of US$2580 billion in 2020-50 would be four times greater than the cumulative treatment costs of $594 billion, producing a net benefit of $1986 billion on the global investment: a net return of $3 for every $1 invested. In sum, the burden of childhood cancer, which has been grossly underestimated in the past, can be effectively diminished to realise massive health and economic benefits and to avert millions of needless deaths.

A comparison of asparaginase activity in generic formulations of E.coli derived L- asparaginase: In-vitro study and retrospective analysis of asparaginase monitoring in pediatric patients with leukemia

AIMS

L-asparaginase is an essential medicine in the treatment of pediatric acute lymphoblastic leukemia (ALL) and the quality of generic formulations is an area of concern. We compared nine generic formulations of L-asparaginase available in India with the innovator.

METHODS

The quality of formulations was assessed by measuring 72-hour trough asparaginase activity in children with ALL during induction following administration of 10,000 IU/m² of L-asparaginase. In-vitro analysis of the label claim was assessed by measuring activity of three generic formulations. Liquid chromatography-mass spectrometry (LC/MS) was used to determine the amount of host contaminant proteins (HCPs) in the formulations.

RESULTS

Between March 2015 to June 2018, 240 samples from 195 patients were analyzed. The number of samples analyzed ranged from 7-66 per generic brand (median: 18) and seven of the innovator. The proportion of generic formulations that failed to achieve a predefined clinical threshold activity of 50 IU/L ranged from 16.7% (2/12) to 84.9% (28/33) in the highest activity to lowest activity generic respectively. On other hand, all innovator samples had activity greater than 50 IU/L. In-vitro asparaginase activity in the three generic formulations tested ranged from 71.4-74.6% of the label claim (10,000 IU) compared to 93.5% for the innovator. LC/MS analysis of generic 5 identified 25 HCPs with a relative peptide count of 27.1% of the total peptides.

CONCLUSIONS

Generic formulations had lower asparaginase activity which raises serious clinical concerns regarding their quality. Until stringent regulatory enforcement improves the quality of these generics, dose adaptive strategies coupled with therapeutic drug monitoring need to be considered.

Clinical profile and outcome of classical Hodgkin lymphoma treated with a risk-adapted approach in a tertiary cancer center in India

BACKGROUND

Classical Hodgkin lymphoma (cHL) has excellent survival rates, but late effects are an issue and dictate modern approaches. We analyzed the clinical profile and outcome of cHL treated on a risk-adapted approach aimed at reducing late effects while improving historical outcomes at our center.

PROCEDURE

Children (≤15 years) consecutively treated for cHL from January 2013 through December 2016 were retrospectively analyzed. ¹⁸ FDG-PET-CT-based staging and response assessment was done after two cycles for early response (ERA) and end of chemotherapy (late-response assessment [LRA]) if not in complete response (CR; Deauville < 4) at ERA. Stages IA/IB/IIA were low risk (LR) and received two cycles of ABVD (adriamycin/bleomycin/vinblastine/dacarbazine). Stages IAX/IBX/IIAX/IIB/IIIA were intermediate risk (IR), and stages IIBE/IIBX/IIIAE/IIIAX/IIIB/IVA/IVB were high risk (HR). Both received two cycles of OEPA (oncocristine/etoposide/prednisolone/adriamycin). Those in ERA-CR received two cycles of ABVD if LR, and two and four cycles of COPDac (cyclophosphamide/oncocristine/prednisolone/dacarbazine), respectively, for IR and HR. Involved-field radiotherapy (IFRT) was given to bulky sites and ERA < CR. Those at LRA < CR (Deauville < 3) or progression at any stage received salvage regimens.

RESULTS

In the study period, 126 patients were identified who received the above protocol. There were 12 LR, and 114 advanced staged Hodgkin lymphoma (AHL) (18, IR; 96, HR) of which 91 (79.8%) had bulky sites. Eight (66.6%) LR and 93 (83%) AHL patients achieved ERA-CRs. IFRT was given to 4 (33.3%) LR patients with ERA < CR, and 92 (80.7%) of AHL (91 bulky sites; 1 ERA < CR). At a median follow-up of 31 months (range, 17-62), three-year event-free survival (EFS) and overall survival (OS) were both 100% for LR, and 94.4% (95% CI, 66.0%-99.2%) for IR, whereas for HR it was 90.3% (95% CI, 82.2%-94.8%) and 92.6% (95% CI, 85.2%-96.4%), respectively.

CONCLUSIONS

Children with HL have favorable outcomes with manageable toxicities when treated on a risk-stratified and adapted approach. A high proportion of AHL have bulky disease necessitating IFRT, a concern that will have to be factored in future strategies.

Phase I/II Study of Palliative Triple Metronomic Chemotherapy in Platinum-Refractory/Early-Failure Oral Cancer

PURPOSE

Platinum-resistant oral cancer has a dismal outcome with limited treatment options. We conducted a phase I/II study to identify the optimal biologic dose (OBD) of methotrexate when given along with erlotinib and celecoxib and to assess the efficacy of this three-drug regimen in advanced oral cancer.

METHODS

Patients with platinum-resistant or early-failure squamous cell carcinoma of the oral cavity were eligible for this study. They were orally administered erlotinib 150 mg once per day, celecoxib 200 mg twice per day, and methotrexate per week. The primary end point of phase I was to determine the OBD of methotrexate, and that of phase II was to determine the 3-month progression-free survival. The OBD of methotrexate was determined on the basis of the clinical benefit rate at 2 months and circulating endothelial cell level at day 8, using a de-escalation model. Pharmacokinetic evaluation was performed during phase I. Phase II consisted of an expansion cohort of 76 patients.

RESULTS

Fifteen patients were recruited in phase I, and 9 mg/m2 methotrexate was identified as the OBD. A total of 91 patients were recruited, and the median follow-up was 6.8 months (range, 0 to 16.8 months). The 3-month progression-free survival rate was 71.1% (95% CI, 60.5% to 79.3%), the 6-month overall survival rate was 61.2% (95% CI, 49.2% to 67.8%), and the response rate was 42.9% (95% CI, 33.2% to 53.1%; n = 39). The mean Functional Assessment of Cancer Therapy-Head and Neck Trial Outcome Index score at day 8 was improved by 6.1 units (standard deviation, 13.6 units) and was maintained around this magnitude ( P = .001).

CONCLUSION

Triple oral metronomic chemotherapy with erlotinib, methotrexate, and celecoxib is efficacious in platinum-refractory oral cavity cancers and represents a new therapeutic option in patients with poor prognosis.

Outcomes in Treatment-Naïve Patients With Metastatic Extremity Osteosarcoma Treated With OGS-12, a Novel Non-High-Dose Methotrexate-Based, Dose-Dense Combination Chemotherapy, in a Tertiary Care Cancer Center

Purpose

Metastatic osteosarcoma is largely treated with high-dose methotrexate (HDMTX)–based therapy, especially in the pediatric population. This mandates complex pharmacokinetic monitoring in a costly inpatient setting to mitigate unpredictable serious toxicities. Hence, a non-HDMTX–based regimen is worth exploring, especially in India and low- and middle-income countries.

Materials and Methods

All consecutive treatment-naïve patients with metastatic osteosarcoma were prospectively treated on the novel OGS-12 protocol consisting of sequential doublets of doxorubicin, cisplatin, and ifosfamide. Four cycles were administered as neoadjuvant therapy followed by planned curative intent surgery and metastasectomy when feasible, followed by four cycles of adjuvant chemotherapy. Baseline characteristics, histologic response, event-free survival (EFS), overall survival (OS), and toxicity data were prospectively collected.

Results

Three hundred seventeen patients were enrolled onto the OGS-12 protocol from 2011 to 2014, of whom 80 (25%) had metastatic disease; median age was 17 years. The majority of patients were nutritionally challenged with high-risk features. At presentation, 83% of patients (66 patients) had lung metastases. After neoadjuvant chemotherapy, 57% of patients were histologically good responders. Four-year EFS and OS rates were 24% and 27%, respectively, in the intent-to-treat population and 27% and 29%, respectively, in the per-protocol analysis. Significant grade 3 or 4 toxicities were febrile neutropenia (51%), thrombocytopenia (36%), and anemia (54%). Histologic response was an independent predictor for EFS and OS in patients who underwent surgery. Surgical intervention was found to be significant for survival in univariable analysis.

Conclusion

The novel, low-cost, non-HDMTX–based, dose-dense OGS-12 regimen has shown comparable outcomes to international standards in metastatic osteosarcomas and is worthy of wider clinical application. An aggressive multimodality approach may result in long-term survival in a select group of patients and, hence, is worth considering.