Outcome of childhood acute Lymphoblastic leukemia in Egyptian children: a challenge for limited health resource countries

Cytogenetic abnormalities and TP53 and RAS gene profiles of childhood acute lymphoblastic leukemia in Morocco

BACKGROUND

Recurrent genetic abnormalities affecting pivotal signaling pathways are the hallmark of childhood acute lymphoblastic leukemia (ALL). The identification of these aberrations remains clinically important. Therefore, we sought to determine the cytogenetic profile and the mutational status of TP53 and RAS genes among Moroccan childhood cases of ALL.

METHODS

In total, 35 patients with childhood ALL were enrolled in the study. The diagnosis and treatment were established in the Pediatric Hematology and Oncology Center at the Children's Hospital of Rabat. Chromosome banding analysis and fluorescence in situ hybridization were used to detect genetic aberrations. Blood samples were screened for TP53 and RAS mutations using Sanger sequencing.

RESULTS

Of the 35 cases, 30 were B-lineage ALL (85.7 %). Moreover, a male predominance was observed. Cytogenetic analysis revealed chromosomal anomalies in 27 cases (77.1 %). The most frequent aberrations were high hyperdiploidy and BCR/ABL rearrangement. Interestingly, we found the rare t(15;16) and the t(8;14), which are uncommon translocations in pediatric B-ALL. The mutational analysis revealed Pro72Arg (rs1042522:C > G) and Arg213Arg (rs1800372:A > G) in TP53. In correlation with cytogenetic data, rs1042522:C > G showed a significant association with the occurrence of chromosomal translocations (p = 0.04). However, no variant was detected in NRAS and KRAS genes.

CONCLUSION

Our findings emphasize the significance of detecting chromosomal abnormalities as relevant prognostic markers. We also suggest a low occurrence of genetic variants among Moroccan children with ALL.

Cyclin D2 gene variance and expression level in pediatric acute lymphoblastic leukemia

BACKGROUND

Cyclin D2 (CCND2) is a crucial player in cell cycle regulation. CCND2 polymorphisms contribute to cancer predisposition.

OBJECTIVES

To evaluate the association of CCND2 rs3217927 single nucleotide polymorphisms (SNP) and its expression levels with acute lymphoblastic leukemia (ALL) susceptibility in Egyptian children and its potential prognostic role.

METHODS

The 5' nuclease allelic discrimination assay was used to evaluate the frequency of CCND2 rs3217927 SNP in 80 newly diagnosed children with ALL and 80 age- and sex-matched controls. CCND2 relative expression levels were determined by real-time quantitative polymerase chain reaction.

RESULTS

The genotype analysis revealed that the GG genotype and G allele were significantly more prevalent among ALL patients than controls (p ˂ .001). Regression analysis demonstrated that Egyptian children carrying only one G allele had about 31-fold increased risk to develop ALL compared to A allele carriers. CCND2 was overexpressed in ALL patients compared to controls (p < .001). The CCND2 overexpression was associated with the GG genotype and G allele (p < .001). Furthermore, G allele was an independent negative prognostic marker for central nervous system (CNS) involvement (odds ratio [OR] = 4.676; 95% confidence interval [CI]: 1.2-18.6), risk stratification (OR = 38; 95% CI: 7.7-188.2), and chemoresistance (OR = 9.864; 95% CI: 5.6-70.3) in ALL patients.

CONCLUSIONS

G allele of CCND2 rs3217927 SNP might be associated with increased risk for ALL in Egyptian children besides being an independent negative prognostic marker for their risk stratification and therapeutic outcome. CCND2 rs3217927 SNP genotyping might be used to demarcate ALL patients with aggressive disease phenotypes who may be candidate for alternative targeted therapeutic strategies.

Barriers to Care and Outcomes of Pediatric Acute Lymphoblastic Leukemia Treatment in the Gaza Strip

BACKGROUND

Childhood acute lymphoblastic leukemia (ALL) is the most common pediatric cancer worldwide. Although children in high-income countries enjoy survival rates of ~90%, children in countries with limited resources suffer from survival rates of <35%. No published data on pediatric cancer incidence, management, or outcomes in the Gaza Strip are available.

METHODS

A retrospective cohort study was undertaken for pediatric (below 12 y of age) ALL diagnoses admitted to the only pediatric cancer ward in the Gaza Strip between 2010 and 2015. Outcomes included event-free survival (EFS) and overall survival (OS) calculated by Kaplan-Meier estimates. Events were defined as induction failure, relapse, and death.

RESULTS

The 3-year EFS estimate was 80% (95% confidence interval [CI], 66%-89%). The EFS at 1 and 3 years for high-risk ALL was 55% (95% CI, 27%-76%) and 23% (95% CI, 4%-51%), respectively. The 3-year OS was 93% (95% CI, 82%-97%). The 3-year OS for high-risk ALL was 69% (95% CI, 30%-90%). All 84 (100%) patients required referral to an outside hospital for definitive ALL diagnoses and induction therapy. Forty-four (52%) patients required at least one additional referral.

CONCLUSIONS

The overall outcomes demonstrated relatively high survival rates at 3 years which may be artificially elevated due to exclusion of adolescents, limited follow up, and deceased patient charts unavailable. Structural determinants of health in Gaza lead to limited diagnostic and treatment capabilities, limited access to advanced medical training, and reliance on out-of-territory transfers for care. These barriers impact the access to comprehensive pediatric care within the Gaza Strip.

Treatment outcomes for childhood acute lymphoblastic leukemia in low-middle income country before minimal residual disease risk stratification

BACKGROUND

Outcome of childhood acute lymphoblastic leukemia (ALL) in low- and middle-income countries is lagging in many aspects including diagnosis, risk stratification, access to treatment and supportive care.

OBJECTIVE

to report the outcome of childhood ALL at Ain Shams University Children's Hospitals with the use of risk-based protocols before the implementation of minimal residual disease technology and to evaluate the use of double delayed intensification (DDI) in standard risk patients.

METHODS

Two hundred and twenty patients with ALL diagnosed between January 2005 and December 2014 were included in the study. Patients were treated according to a modified CCG 1991 and 1961 for standard and high risk respectively. Patients were stratified into three risk groups: standard risk (SR), high-risk standard arm (HR-SA), and high-risk augmented arm (HR-AA).

RESULTS

Among the whole cohort, the 10-year event-free survival (EFS) and overall survival (OS) were 78.1% and 84.3% respectively. Patients with Pre-B immunophenotype (IPT) had significantly better outcome than T-cell IPT (EFS 82.0% versus 58.6%, p < 0.001; OS 86.9% versus 69%, p = 0.003 for Pre-B and T-cell respectively). Among the SR group, patients treated with single delayed intensification (SDI) had comparable EFS and OS rates when compared to patients treated with DDI with EFS 82.4% versus 87.5%, p = 0.825 and OS 88.2% versus 93.5%, p = 0.638 for SDI and DDI groups, respectively.

CONCLUSION

The use of risk-based protocol with simple laboratory techniques resulted in acceptable survival outcome in resource limited settings. The use of double delayed intensification showed no survival advantage in patients with standard risk.

Treatment outcomes of children with acute lymphoblastic leukemia in a middle-income developing country: high mortalities, early relapses, and poor survival

OBJECTIVE

Acute lymphoblastic leukemia is the most common childhood cancer, yet surprisingly, very few studies have reported the treatment outcomes and the relapse rate of patients from low/middle-income countries.

METHOD

This study was a 5-year retrospective cohort study. It was conducted at Oncology Center of Mansoura University in Egypt and aimed to estimate the treatment outcomes and the relapse rates of newly diagnosed acute lymphoblastic leukemia in children.

RESULTS

Two hundred children suffering from acute lymphoblastic leukemia were studied; forty-six patients (23%) died during induction and most of those deaths were related to infection. Forty-one patients (27%) relapsed out of the 152 patients who achieved complete remission. The most common site of relapse was the bone marrow, followed by the isolated central nervous system, 53.7% and 31.7%, respectively. Seventy-eight percent of relapses occurred very early/early rather than later. The majority of relapse patients' deaths were related to infection and disease progression. The 5-year overall survival rate for patients was 63.1% (82.1% for non-relapsed compared to 36.6% for relapsed patients).

CONCLUSION

There was a high incidence of induction deaths related to infection and high percentages of very early/early relapses, with high mortalities and low 5-year overall survival rates. These findings suggest the urgent need for modification of chemotherapy regimens to be suitable for the local conditions, including implementation of supportive care and infection control policies. There is also a requirement for antimicrobial prophylaxis during induction period combined with the necessary increase in government healthcare spending to improve the survival of acute lymphoblastic leukemia in Egyptian children.

ARID5B rs10821936 and rs10994982 gene polymorphisms and acute lymphoblastic leukemia: relation to disease susceptibility and outcome

ARID5B rs10821936 and rs10994982 single nucleotide polymorphism (SNP) have been associated with the risk of acute lymphoblastic leukemia (ALL) in different ethnic populations. We investigated the association between the ARID5B rs10821936 C > T, rs10994982 A > G, and susceptibility to ALL in a cohort of Egyptian individuals and investigated their role in relation to disease outcome. Real-time PCR typing was done for ARID5B rs10821936 and rs10994982 SNPs for 128 pediatric ALL (pALL), 45 adult ALL (aALL), and 436 healthy controls. Significant risk associations were found between the C allele (p < 0.001, OR = 2.02), CC genotype (p < 0.001, OR = 2.72), CT genotype (p = 0.011, OR = 1.45) of ARID5B rs10821936 and pediatric ALL especially T-ALL and adult ALL (p < 0.05). The CA haplotype (C allele of rs10821936 + A allele of rs10994982) was associated with the risk of ALL either pediatric ALL or adult ALL (p < 0.001). In the studied Egyptian population, it can be concluded that the C allele, CC, and CT genotypes of ARID5B rs10821936 and the CA haplotype may be a susceptibility risk factor for pediatric and adult ALL. However, the SNPs of ARID5B rs10821936 and rs10994982 were not found to be strongly associated with ALL outcomes.

Cytogenetic Profile and FLT3 Gene Mutations of Childhood Acute Lymphoblastic Leukemia

Background:

Childhood acute lymphoblastic leukemia (ALL) is characterized by recurrent genetic aberrations. The identification of those abnormalities is clinically important because they are considered significant risk-stratifying markers.

Aims:

There are insufficient data of cytogenetic profiles in Saudi Arabian patients with childhood ALL leukemia. We have examined a cohort of 110 cases of ALL to determine the cytogenetic profiles and prevalence of FLT3 mutations and analysis of the more frequently observed abnormalities and its correlations to other biologic factors and patient outcomes and to compare our results with previously published results.

Materials and methods:

Patients—We reviewed all cases from 2007 to 2016 with an established diagnosis of childhood ALL. Of the 110 patients, 98 were B-lineage ALL and 12 T-cell ALL. All the patients were treated by UKALL 2003 protocol and risk stratified according previously published criteria. Cytogenetic analysis—Chromosome banding analysis and fluorescence in situ hybridization were used to detect genetic aberrations. Analysis of FLT3 mutations—Bone marrow or blood samples were screened for FLT3 mutations (internal tandem duplications, and point mutations, D835) using polymerase chain reaction methods.

Result:

Cytogenetic analysis showed chromosomal anomalies in 68 out of 102 cases with an overall incidence 66.7%. The most frequent chromosomal anomalies in ALL were hyperdiploidy, t(9;22), t(12;21), and MLL gene rearrangements. Our data are in accordance with those published previously and showed that FLT3 mutations are not common in patients with ALL (4.7%) and have no prognostic relevance in pediatric patients with ALL. On the contrary, t(9;22), MLL gene rearrangements and hypodiploidy were signs of a bad prognosis in childhood ALL with high rate of relapse and shorter overall survival compared with the standard-risk group (P = .031).The event-free survival was also found to be worse (P = .040).

Conclusions:

Our data are in accordance with those published previously, confirming the overall frequency of cytogenetic abnormalities and their prognostic relevance.

Assessment of Obesity and Hepatic Late Adverse Effects in the Egyptian Survivors of Pediatric Acute Lymphoblastic Leukemia: a Single Center Study

Background

Childhood acute lymphoblastic leukemia (ALL) with current cure rates reaching 80% emphasizes the necessity to determine treatment-related long-term effects. The aim of this study is to estimate the prevalence of overweight, obesity, and hepatic late adverse effects in a cohort of ALL survivors treated at the Hematology and Oncology Unit, Pediatrics Department, Menoufia University, Egypt.

Methods

In this case-control study, height, weight, and body mass index (BMI) were assessed for 35 pediatric ALL survivors and 35 healthy children. These parameters were plotted on the growth and WHO standard deviation charts for both males and females. Overweight and obesity were defined by BMI > 85^th and 95^th percentile respectively. Laboratory investigations were done in the form of iron profile, liver enzymes, total and direct bilirubin levels, serum urea &creatinine and detection of hepatitis C virus antibodies by ELISA.

Results

The weight and BMI were significantly greater in the survivors than controls (P value =0.002 and 0.039 respectively). ALT, total & direct bilirubin, serum ferritin and transferrin saturation were considerably higher in the survivors than the controls (P value = 0.03, 0.036, 0.044, 0.006 and 0.03 respectively). Ten (28.6%) of survivors had hepatitis C antibodies with none (0%) of controls (P value =0.02)

Conclusions

Pediatric ALL survivors are at increased risk of overweight/obesity, hepatic dysfunction in the form of elevated liver enzymes, bilirubin levels, and C viral hepatitis. Screening of those survivors for such complications should be considered.

The Impact of Socioeconomic Factors on the Outcome of Childhood Acute Lymphoblastic Leukemia (ALL) Treatment in a Low/Middle Income Country (LMIC)

Survival for childhood acute lymphoblastic leukemia (ALL) has improved significantly, but these benefits may not be available to many children from low and middle income countries, where reasons for treatment failure may be unique to their environment. We retrospectively reviewed data on pediatric (1 to 18 y or younger) patients with newly diagnosed ALL treated over 5 years at a children's cancer hospital in Pakistan. Patients were treated with modified Berlin-Frankfurt-Muenster -based therapy without risk stratification. There were 255 children with a median age of 7 years (mean, 7.65 y) and a male preponderance (M:F=1.6:1). 20% had T-ALL, one-third had white blood cells >50×10/L and 13.7% central nervous system disease. A majority (56.5%) was malnourished. In total, 49 (19.2%) died before the end of induction and 21 died in complete remission. Most deaths were infection-related. A total of 50 patients relapsed and 19 abandoned therapy after complete remission. Five-year overall survival is 52.9% with abandonment censored and 45.8% with abandonment as an event. Overall survival was related to socioeconomic status but not to known risk factors. The outcome of ALL at our center is suboptimal and associated with factors not commonly seen in developed countries. Special attention to early diagnosis, infection control, and parental educational are needed to improve the survival.

Identifying causes of variability in outcomes in children with acute lymphoblastic leukemia treated in a resource-rich developing country

BACKGROUND

The outcome of children with acute lymphoblastic leukemia (ALL) in developing countries is less favorable than in developed countries, primarily due to resource constraints. However, it is unknown whether the therapeutic results differ. Thus, we hypothesized that outcomes in resource-rich developing countries would be similar to those in industrialized regions.

PROCEDURE

We performed a retrospective analysis of 224 consecutive children with ALL, who were treated according to the Children's Cancer Group (CCG) protocols between January 2001 and December 2007. High-risk (HR) and standard-risk (SR) patients were treated with modified CCG-1961 and CCG-1991 protocols, respectively. Modifications included substitution of dexamethasone for prednisone in HR patients and addition of two intrathecal methotrexate treatments for CNS2 patients during induction. All patients received double delayed intensification with two interim maintenance phases.

RESULTS

Five-year overall survival (OS), event-free survival (EFS) and disease-free survival (DFS) were 84.7 ± 2.4%, 77.0 ± 2.9%, and 81.4 ± 2.7%, respectively. Remission was achieved in 98.1% of the patients. Induction failure and relapse rates were 1.9% and 15.1%, respectively. Death as the first event occurred in 6.4% of cases, of which 2.7% and 3.7% involved deaths in induction and remission, respectively. Interestingly, a significant reduction in induction deaths was observed over time.

CONCLUSIONS

Despite the encouraging results observed in the present study, our patients displayed significantly lower survival outcomes compared to subjects treated in major clinical trials conducted by leading leukemia cooperative groups. Furthermore, this work underscores the need for targeted interventions to reduce death as the first event in developing regions.