Sex differences in prognosis for children with acute lymphoblastic leukemia

Prediction of Response to FDA-Approved Targeted Therapy and Immunotherapy in Acute Lymphoblastic Leukemia (ALL)

OPINION STATEMENT

Acute lymphoblastic leukemia (ALL) represents the predominant cancer in pediatric populations, though its occurrence in adults is relatively rare. Pre-treatment risk stratification is crucial for predicting prognosis. Important factors for assessment include patient age, white blood cell (WBC) count at diagnosis, extramedullary involvement, immunophenotype, and cytogenetic aberrations. Minimal residual disease (MRD), primarily assessed by flow cytometry following remission, plays a substantial role in guiding management plans. Over the past decade, significant advancements in ALL outcomes have been witnessed. Conventional chemotherapy has remarkably reduced mortality rates; however, its intensive nature raises safety concerns and has led to the emergence of treatment-resistant cases with recurrence of relapses. Consequently, The U.S. Food and Drug Administration (FDA) has approved several novel treatments for relapsed/refractory ALL due to their demonstrated efficacy, as indicated by improved complete remission and survival rates. These treatments include tyrosine kinase inhibitors (TKIs), the anti-CD19 monoclonal antibody blinatumomab, anti-CD22 inotuzumab ozogamicin, anti-CD20 rituximab, and chimeric antigen receptor (CAR) T-cell therapy. Identifying the variables that influence treatment decisions is a pressing necessity for tailoring therapy based on heterogeneous patient characteristics. Key predictive factors identified in various observational studies and clinical trials include prelymphodepletion disease burden, complex genetic abnormalities, and MRD. Furthermore, the development of serious adverse events following treatment could be anticipated through predictive models, allowing for appropriate prophylactic measures to be considered. The ultimate aim is to incorporate the concept of precision medicine in the field of ALL through valid prediction platform to facilitate the selection of the most suitable treatment approach.

Sex-based disparities in outcome in pediatric acute lymphoblastic leukemia: a Children's Oncology Group report

BACKGROUND

Boys with acute lymphoblastic leukemia (ALL) have historically experienced inferior survival compared to girls. This study determined whether sex-based disparities persist with contemporary therapy and whether patterns of treatment failure vary by sex.

METHODS

Patients 1 to 30.99 years old were enrolled on frontline Children's Oncology Group trials between 2004 and 2014. Boys received an additional year of maintenance therapy. Sex-based differences in the distribution of various prognosticators, event-free survival (EFS) and overall survival (OS), and subcategories of relapse by site were explored.

RESULTS

A total of 8202 (54.4% male) B-cell ALL (B-ALL) and 1562 (74.3% male) T-cell ALL (T-ALL) patients were included. There was no sex-based difference in central nervous system (CNS) status. Boys experienced inferior 5-year EFS and OS (EFS, 84.6% ± 0.5% vs 86.0% ± 0.6%, P = .009; OS, 91.3% ± 0.4% vs 92.5% ± 0.4%, P = .02). This was attributable to boys with B-ALL, who experienced inferior EFS (hazard ratio [HR], 1.2; 95% confidence interval [95% CI], 1.1-1.3; P = .004) and OS (HR, 1.2; 95% CI, 1.0-1.4; P = .046) after adjustment for prognosticators. Inferior B-ALL outcomes in boys were attributable to more relapses (5-year cumulative incidence 11.2% ± 0.5% vs 9.6% ± 0.5%; P = .001), particularly involving the CNS (4.2% ± 0.3% vs 2.5% ± 0.3%; P < .0001). There was no difference in isolated bone marrow relapses (5.4% ± 0.4% vs 6.2% ± 0.4%; P = .49). There were no sex-based differences in EFS or OS in T-ALL.

CONCLUSIONS

Sex-based disparities in ALL persist, attributable to increased CNS relapses in boys with B-ALL. Studies of potential mechanisms are warranted. Improved strategies to identify and modify treatment for patients at highest risk of CNS relapse may have particular benefit for boys.

Sex, gender, and retinoblastoma: analysis of 4351 patients from 153 countries

Objective

To investigate in a large global sample of patients with retinoblastoma whether sex predilection exists for this childhood eye cancer.

Methods

A cross-sectional analysis including 4351 treatment-naive retinoblastoma patients from 153 countries who presented to 278 treatment centers across the world in 2017. The sex ratio (male/female) in the sample was compared to the sex ratio at birth by means of a two-sided proportions test at global level, country economic grouping, continent, and for selected countries.

Results

For the entire sample, the mean retinoblastoma sex ratio, 1.20, was higher than the weighted global sex ratio at birth, 1.07 (p < 0.001). Analysis at economic grouping, continent, and country-level demonstrated differences in the sex ratio in the sample compared to the ratio at birth in lower-middle-income countries (n = 1940), 1.23 vs. 1.07 (p = 0.019); Asia (n = 2276), 1.28 vs. 1.06 (p < 0.001); and India (n = 558), 1.52 vs. 1.11 (p = 0.008). Sensitivity analysis, excluding data from India, showed that differences remained significant for the remaining sample (χ² = 6.925, corrected p = 0.025) and for Asia (χ² = 5.084, corrected p = 0.036). Excluding data from Asia, differences for the remaining sample were nonsignificant (χ² = 2.205, p = 0.14).

Conclusions

No proof of sex predilection in retinoblastoma was found in the present study, which is estimated to include over half of new retinoblastoma patients worldwide in 2017. A high male to female ratio in Asian countries, India in specific, which may have had an impact on global-level analysis, is likely due to gender discrimination in access to care in these countries, rather than a biological difference between sexes.

[Gender blindness in medical textbooks: the case of leukemias]

OBJECTIVE

To analyse the existence of sex-differences in the content on leukemias in the Haematology and Internal Medicine textbooks recommended in the Medical Degrees, 2019-2020, by comparison with the sex-differences recognized in the scientific literature.

METHOD

Manifest content analysis of the content of chapters on leukemias in the books on hematology and internal medicine, clinical haematology and haematology undergraduate. Analysis categories: epidemiology, etiopathogenesis, diagnosis, treatment and prognosis of leukemias.

RESULTS

Epidemiological information from the revised books has a greater consideration of sex differences in incidence and prognosis but does not contain data on mortality and survival. Etiopathogenesis is described in all books as the same physiological process for both sexes and no differences in the presentation of symptoms are described in any book. Three books describe a unique treatment that is assumed equal for both sexes; two books mention the treatment of acute myeloid leukemia in pregnant women and one in chronic myeloid leukemia. No book mentions sex-differences in pharmacokinetics, efficacy, or treatment toxicity, although there is greater evidence on unequal behavior between the sexes.

CONCLUSIONS

The contents of sex and gender differences in the leukemia chapters analyzed are insufficient compared to the evidence in the scientific literature today. Hematology textbooks might increase their scientific quality in future editions, including knowledge of sex-gender interaction in the sections of epidemiology, etiology, pathogenesis, diagnosis, treatment, prognosis, and consequences of leukemias, which will contribute to better professional practices, more efficient and equitable.

Sexual Dimorphism in Children and Adolescents With Acute Lymphoblastic Leukemia: Influence on Incidence and Survival

Acute lymphoblastic leukemia (ALL) incidence and poor prognosis are higher in male individuals. There is a lack of studies assessing the influence of sex in ALL. We documented this influence in a homogenous cohort. Three hundred three ALL Hispanic patients 1 to 20 years of age diagnosed over 10 years at a university hospital were evaluated. Patients were divided by sex and stratified by age. Survival rates were assessed by the Kaplan-Meier method, and the Cox model was used for univariate and multivariate analysis. The median age for female individuals was 6 years versus 9 years for male individuals (P=0.002). In the whole cohort, there was a male preponderance (P=0.025), with a 1.3 male-to-female ratio. For male individuals, the 5-year relapse-free survival was 46%; for female individuals, it reached 58.7%, (P=0.009). Male individuals 1-9 years of age had a lower 5-year relapse-free survival than female individuals, 51.5% versus 66.7% (95% confidence interval, 65.35-68.01; P=0.020); this was not the case for overall survival (P=0.660). The male-to-female ratio in the 10 to 15 years' group was 1.59, and 2.35 in the 16 to 20 years' group. Incidence and relapse of ALL were higher in male individuals. A skewed distribution in the 10 to 20 years' age group disproportionately affected male individuals, suggesting a hormonal influence.

Day 15 and Day 33 Minimal Residual Disease Assessment for Acute Lymphoblastic Leukemia Patients Treated According to the BFM ALL IC 2009 Protocol: Single-Center Experience of 133 Cases

Introduction: Childhood acute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by the acquisition of several genetic lesions in the lymphoid progenitors with subsequent proliferation advantage and lack of maturation. Along the years, it has been repeatedly shown that minimal residual disease (MRD) plays an important role in prognosis and therapy choice. The aim of the current study was to determine the prognostic role of MRD in childhood ALL patients in conjunction with other relevant patient and disease characteristics, thus showing the real-life scenario of childhood ALL. Patients and Methods: The retrospective study includes childhood ALL patients that were treated according to the BFM ALL IC 2009 between January 2016 and December 2018 at the Fundeni Clinical Institute, Bucharest, Romania. Results: None of the variables significantly influenced the induction-related death in our study. None of the variables independently predicted relapse-free survival (RFS) with the highest tendency for statistical significance being represented by poor prednisone response. Non-relapse mortality (NRM) was independently predicted by age, prednisone response, and day 33 flow cytometry-MRD (FCM-MRD). Overall survival (OS) was independently predicted by prednisone response and day 33 FCM-MRD. Event-free survival (EFS) was independently predicted by age, prednisone response, and day 33 FCM-MRD. Conclusion : Prednisone response, day 15 FCM-MRD, day 33 FCM-MRD, and the risk group represent the most important factors that in the current study independently predict childhood ALL prognosis.

The survival of patients enrolled in a global direct-to-patient cancer medicine donation program: The Glivec International Patient Assistance Program (GIPAP)

BACKGROUND

The Glivec International Patient Assistance Program (GIPAP) is a unique direct-to-patient program that provides imatinib (Glivec) at no cost to eligible patients in low- and middle-income countries (LMICs) with chronic myelogenous leukemia (CML) or gastrointestinal stromal tumor (GIST). This paper analyses the output, outcome and impact of the program between 2001 and 2014 using the data collected by the Max Foundation.

METHOD

We extracted data on GIPAP patients' country of residence, sex, diagnosis, date of enrollment in GIPAP, age at enrollment, case closure date, and reason for closure from The Max Foundation database covering the period 2001 to 2014. We used Kaplan-Meier method to assess the survival rate of patients in GIPAP and used the proportional hazard regression model to estimate the effect of different variables on patients' survival.

FINDINGS

About 63,000 GIPAP patients in 93 countries received over 71 million defined daily doses (DDD) of imatinib between 2001 and 2014. Our analysis showed that GIPAP patients had a 5-year survival rate of 89% which compares favorably to survival in high income countries despite the challenges of delivering cancer care in LMICs. Age at enrollment into the program, sex, duration between diagnosis and enrollment into program, year of enrollment, and patients' diagnosis (CML vs non-CML) were factors that influenced survival.

INTERPRETATION

The GIPAP program has improved the survival of CML and GIST patients in LMICs, most of whom would not have had access to imatinib in the absence of the donation and therapeutic support of the program.

FUNDING

This work was funded as part of Access Accelerated case studies. Access Accelerated is an initiative of more than 20 global biopharmaceutical companies in partnership with the World Bank and Union of International Cancer Control that seeks to reduce barriers to prevention, treatment and care for non-communicable diseases in LMICs.

How I treat newly diagnosed T-cell acute lymphoblastic leukemia and T-cell lymphoblastic lymphoma in children

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy that has historically been associated with a very poor prognosis. Nevertheless, despite a lack of incorporation of novel agents, the development of intensified T-ALL-focused protocols has resulted in significant improvements in outcome in children. Through the use of several representative cases, we highlight the key changes that have driven these advances including asparaginase intensification, the use of induction dexamethasone, and the safe omission of cranial radiotherapy. We discuss the results of recent trials to explore key topics including the implementation of risk stratification with minimal residual disease measurement and how to treat high-risk subtypes such as early T-cell precursor ALL. In particular, we address current discrepancies in treatment between different cooperative groups, including the use of nelarabine, and provide rationales for current treatment protocols for both T-ALL and T-lymphoblastic lymphoma.

Esophageal Varices in Adolescent and Young Adult Males with Acute Lymphocytic Leukemia

Hepatic late effects are not commonly reported in survivors of childhood leukemia. Four young male patients with acute lymphoblastic leukemia (ALL) were diagnosed with bleeding esophageal varices (EVs) during or shortly after completion of maintenance chemotherapy. EVs were identified from 0 to 60 months after completion of leukemia therapy. All four patients were men between 20 to 24 years old. Hematemesis was the most common presenting symptom. Associated features included splenomegaly, cytopenias, azole therapy, alcohol use, and hepatic iron overload. EVs may be an under-recognized complication of ALL therapy, with adolescent and young adult males at highest risk.

Factors associated with receipt of hematopoietic cell transplantation for acute lymphoblastic leukemia

AIM

To evaluate practice patterns of hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia.

MATERIALS & METHODS

We utilized the National Cancer Database to extract patient-level data of adults (aged 18-80 years) diagnosed with acute lymbhoblastic leukemia between 2003 and 2012. We performed multivariable logistic regression to determine variables associated with the use of HCT.

RESULTS

Out of a total of 11,871 patients, 12.7% received HCT. In a multivariate analysis, older age, male sex, higher Charlson co-morbidity score, nonacademic treatment center, poor education and Medicare/Medicaid or no insurance were associated with lower likelihood of receiving HCT.

CONCLUSION

Our study demonstrates variations in the utilization of HCT based on socioeconomic and health system factors.

Brain structure, working memory and response inhibition in childhood leukemia survivors

INTRODUCTION

Survival rates for children with acute lymphoblastic leukemia (ALL) approach 95%. At the same time, there is growing concern that chemotherapy causes alterations in brain development and cognitive abilities. We performed MRI measurements of white and gray matter volume to explore how variation in brain structure may be related to cognitive abilities in ALL survivors and healthy controls.

METHODS

The sample included 24 male ALL survivors who had completed contemporary treatment 3-11 years prior, and 21 age- and sex-matched controls. Participants were between 8 and 18 years old. Working memory and motor response inhibition were measured with the N-Back and Stop Signal Tasks (SST), respectively. Participants underwent 3T structural MRI to assess white and gray matter volumes overall, lobe-wise, and in cortical and atlas-identified subcortical structures. Mental health was assessed with the Child Behavioral Checklist.

RESULTS

ALL survivors performed more poorly on measures of working memory and response inhibition than controls. Frontal and parietal white matter, temporal and occipital gray matter volume, and volumes of subcortical white and gray matter structures were significantly reduced in ALL survivors compared with controls. Significant structure-function correlations were observed between working memory performance and volume of the amygdala, thalamus, striatum, and corpus callosum. Response inhibition was correlated with frontal white matter volume. No differences were found in psychopathology.

CONCLUSIONS

Compared with controls, a reduction in volume across brain regions and tissue types, was detectable in ALL survivors years after completion of therapy. These structural alterations were correlated with neurocognitive performance, particularly in working memory. Confirming these observations in a larger, more representative sample of the population is necessary. Additionally, establishing the time course of these changes-and the treatment, genetic, and environmental factors that influence them-may provide opportunities to identify at-risk patients, inform the design of treatment modifications, and minimize adverse cognitive outcomes.

Survival From Childhood Hematological Malignancies in Denmark: Is Survival Related to Family Characteristics?

BACKGROUND

Due to diverse findings as to the role of family factors for childhood cancer survival even within Europe, we explored a nationwide, register-based cohort of Danish children with hematological malignancies.

METHODS

All children born between 1973 and 2006 and diagnosed with a hematological malignancy before the age of 20 years (N = 1,819) were followed until 10 years from diagnosis. Kaplan-Meier curves and Cox proportional hazards models estimating hazard ratios (HR) and 95% confidence intervals (CI) were used to assess the impact of family characteristics on overall survival in children with hematological malignancies.

RESULTS

Having siblings and increasing birth order were associated with reduced survival from acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). Associations with AML were strongest and statistically significant. HRs of 1.62 (CI 0.85; 3.09) and 5.76 (CI 2.01; 16.51) were observed for the fourth or later born children with ALL (N = 41) and AML (N = 9), respectively. Children with older parents showed a tendency toward inferior ALL survival, while for AML young maternal age was related to poorer survival. Based on small numbers, a trend toward poorer survival from non-Hodgkin lymphoma was observed for children having siblings and for children of younger parents.

CONCLUSIONS

Further research is warranted to gain further knowledge on the impact of family factors on childhood cancer survival in other populations and to elaborate potential underlying mechanisms and pathways of those survival inequalities.

Differential inequality trends over time in survival among U.S. children with acute lymphoblastic leukemia by race/ethnicity, age at diagnosis, and sex

BACKGROUND

It is unclear how inequalities in survival among children with acute lymphoblastic leukemia (ALL) have changed over time in different race/ethnicity groups.

METHODS

Children diagnosed with a first primary malignant ALL at ages 0 to 19 years in 1975-2010 in the nine Surveillance, Epidemiology, and End Results cancer registries were included. Cumulative ALL mortalities were compared, and multivariable Cox regression analyses were applied to estimate ALL mortality HRs associated with race/ethnicity, age at diagnosis, and sex, adjusting for each other, within each diagnosis period (1975-1983, 1984-1991, 1992-1999, and 2000-2010).

RESULTS

Compared with non-Hispanic-whites (NH-whites), the HR in non-Hispanic-blacks (NH-blacks) dropped to 1.21 [95% confidence interval (CI), 0.74-1.96] in 2000-2010 from the largest inequality in 1984-1991 (HR, 2.09; 95% CI, 1.57-2.79); the HR in Hispanics increased, however, from 1.28 (95% CI, 0.98-1.66) in 1975-1983 to 1.95 (95% CI, 1.48-2.58) in 2000-2010. Asian/Pacific Islanders (API) and American Indian/Alaska Natives (AIAN) had HRs of 1.39 (95% CI, 0.92-2.11) and 2.31 (95% CI, 1.13-4.74), respectively, in 2000-2010 with nonstatistically significant increases over time. In 2000-2010, compared with NH-white counterparts, NH-blacks and APIs diagnosed at 1-9 years, Hispanics diagnosed at 1-9 and 10-19 years, and AIANs diagnosed at 10-19 years all had about twice the ALL mortality hazard rates; inequality was observed among API boys (HR, 1.61; 95% CI, 1.00-2.60) but not API girls.

CONCLUSIONS

Survival inequalities changed differently across subgroups of children with ALL.

IMPACT

Underlying causes of the differential trends need to be examined, such that targeted interventions can be developed to reduce inequalities.

Family circumstances and survival from childhood acute lymphoblastic leukaemia in West Germany

BACKGROUND

Little is known about the relationship between family characteristics and survival from childhood acute lymphoblastic leukaemia (ALL), which we studied for the first time in German children.

METHODS

ALL cases were diagnosed between 1992 and 1994 and information on family characteristics was collected during a previously conducted nationwide case-control study. Children were followed for 10 years after diagnosis, as few disease-related events occur afterwards. Cox proportional hazards models estimating hazard ratios (HR) were calculated using overall as well as event-free survival methods.

RESULTS

Second born children showed statistically significant better survival compared to first or later born children, with HRs ranging between 0.54 and 0.64 compared to firstborns. Somewhat poorer survival was observed for children having 3 or more siblings. A relationship was found for parental age at child's diagnosis, with poorer survival for children with younger parents (≤25 years of age at child's diagnosis), or with older fathers. The HR was statistically significant for fathers being ≥41years of age (HR of 2.1). No relationship between degree of urbanization of the place of residence at diagnosis and ALL survival was observed.

CONCLUSION

Family circumstances may have an impact on survival from childhood ALL in Germany. Further research is warranted to elaborate the relationship of specific family characteristics and ALL survival and to investigate possible differential adherence to therapy and interactions with physicians.

Hematopoietic stem cell transplantation following unsuccessful salvage treatment for relapsed acute lymphoblastic leukemia in children

BACKGROUND

For children who experience a re-induction failure or multiple recurrences following the first relapse of acute lymphoblastic leukemia (ALL), it is uncertain whether additional intensive chemotherapy aimed at hematopoietic stem cell transplantation (SCT) in complete remission (CR) or immediate SCT even in non-CR should be performed. This study aimed to investigate the impact of disease status at SCT on the outcomes of SCT for these children, whose prognosis is considered unquestionably poor even with SCT.

PROCEDURE

The medical records of 55 children with ALL who underwent SCT following the experience of re-induction failure (n = 25) or multiple relapses (n = 30) were retrospectively analyzed.

RESULTS

Twenty-one patients underwent SCT in CR (delayed CR2, CR3, and CR4) and 34 in non-CR (first or subsequent relapse). The probability of overall survival of patients with CR and with non-CR at SCT was 42.9% and 23.5% (P = 0.15), leukemia-free survival was 38.1% and 20.6% (P = 0.18), and the cumulative incidence of relapse at 2 years was 23.8% and 50%, respectively (P = 0.05). In multivariate analysis, non-CR at SCT was a significant risk factor for higher relapse incidence and male sex was a significant risk factor for lower survival.

CONCLUSIONS

Our results indicated that in case of tolerable patient condition, further re-induction chemotherapy might be reasonable so that SCT could be performed in CR, which might result in a low incidence of relapse after SCT. Novel approaches are required to induce CR for the treatment of children with relapsed/refractory ALL.

Mercaptopurine/Methotrexate maintenance therapy of childhood acute lymphoblastic leukemia: clinical facts and fiction

The antileukemic mechanisms of 6-mercaptopurine (6MP) and methotrexate (MTX) maintenance therapy are poorly understood, but the benefits of several years of myelosuppressive maintenance therapy for acute lymphoblastic leukemia are well proven. Currently, there is no international consensus on drug dosing. Because of significant interindividual and intraindividual variations in drug disposition and pharmacodynamics, vigorous dose adjustments are needed to obtain a target degree of myelosuppression. As the normal white blood cell counts vary by patients' ages and ethnicity, and also within age groups, identical white blood cell levels for 2 patients may not reflect the same treatment intensity. Measurements of intracellular levels of cytotoxic metabolites of 6MP and MTX can identify nonadherent patients, but therapeutic target levels remains to be established. A rise in serum aminotransferase levels during maintenance therapy is common and often related to high levels of methylated 6MP metabolites. However, except for episodes of hypoglycemia, serious liver dysfunction is rare, the risk of permanent liver damage is low, and aminotransferase levels usually normalize within a few weeks after discontinuation of therapy. 6MP and MTX dose increments should lead to either leukopenia or a rise in aminotransferases, and if neither is experienced, poor treatment adherence should be considered. The many genetic polymorphisms that determine 6MP and MTX disposition, efficacy, and toxicity have precluded implementation of pharmacogenomics into treatment, the sole exception being dramatic 6MP dose reductions in patients who are homozygous deficient for thiopurine methyltransferase, the enzyme that methylates 6MP and several of its metabolites. In conclusion, maintenance therapy is as important as the more intensive and toxic earlier treatment phases, and often more challenging. Ongoing research address the applicability of drug metabolite measurements for dose adjustments, extensive host genome profiling to understand diversity in treatment efficacy and toxicity, and alternative thiopurine dosing regimens to improve therapy for the individual patient.

Characterization of pediatric acute lymphoblastic leukemia survival patterns by age at diagnosis

Age at diagnosis is a key prognostic factor in pediatric acute lymphoblastic leukemia (ALL) survivorship. However, literature providing adequate assessment of the survival variability by age at diagnosis is scarce. The aim of this study is to assess the impact of this prognostic factor in pediatric ALL survival. We estimated incidence rate of mortality, 5-year survival rate, Kaplan-Meier survival function, and hazard ratio using the Surveillance Epidemiology and End Results (SEER) data during 1973–2009. There was significant variability in pediatric ALL survival by age at diagnosis. Survival peaked among children diagnosed at 1–4 years and steadily declined among those diagnosed at older ages. Infants (<1 year) had the lowest survivorship. In a multivariable Cox proportional hazard model stratified by year of diagnosis, those diagnosed in age groups 1–4, 5–9, 10–14, and 15–19 years were 82%, 75%, 57%, and 32% less likely to die compared to children diagnosed in infancy, respectively. Age at diagnosis remained to be a crucial determinant of the survival variability of pediatric ALL patients, after adjusting for sex, race, radiation therapy, primary tumor sites, immunophenotype, and year of diagnosis. Further research is warranted to disentangle the effects of age-dependent biological and environmental processes on this association.

Survival from childhood acute lymphoblastic leukaemia in West Germany: does socio-demographic background matter?

BACKGROUND

Sex, age, immunophenotype and white blood cell count at diagnosis are well accepted predictors of survival from acute lymphoblastic leukaemia (ALL) in children. Less is known about the relationship between socio-economic determinants and survival from paediatric ALL, studied here for the first time in German children.

METHODS

ALL cases were diagnosed between 1992 and 1994 and their parents interviewed during a previous nationwide case-control study. Children were followed-up for 10 years after diagnosis by the German Childhood Cancer Registry. Cox proportional hazards models estimating hazard ratios (HRs) were calculated to assess the impact of selected socio-demographic characteristics on overall and event-free survival.

RESULTS

Overall survival was 82.5%, with a higher proportion of girls than boys surviving (85% versus 81%). We found a non-linear relationship between age at diagnosis and survival, with poorer survival in infants and children aged >5 years. There was no association between socio-economic factors and survival or risk of relapse. For five levels of increasing family income, all HRs were close to one. No relationship was seen with parental educational level.

CONCLUSION

Socio-economic determinants did not affect ALL survival in West German children, in contrast to studies from some other countries. Dissimilarities in social welfare systems, including access to health care, lifestyle and differences in treatment may contribute to these differences in findings. Our observation of no social inequalities in paediatric ALL survival is reassuring, but needs continued monitoring to assess the potential impact of evolvement of treatment options and changes in paediatric health service.

Asparaginase in the treatment of non-ALL hematologic malignancies

Asparaginases are among the most effective agents against acute lymphoblastic leukemia (ALL) and are Food and Drug Administration-approved for the treatment of pediatric and adult ALL. However, the efficacy of these drugs for the treatment of other hematologic malignancies particularly acute myeloid leukemia is not well established. The mechanism of action of asparaginases has thought to be related to a swift and sustained reduction in serum L-asparagine, which is required for rapid proliferation of metabolically demanding leukemic cells. However, asparagine depletion alone appears not to be sufficient for effective cytotoxic activity of asparaginase against leukemia cells, because glutamine can rescue asparagine-deprived cells by regeneration of asparagine via a transamidation chemical reaction. For this reason, glutamine reduction is also necessary for full anti-leukemic activity of asparaginase. Indeed, both Escherichia coli and Erwinia chrysanthemi asparaginases possess glutaminase enzymatic activity, and their administrations have shown to reduce serum glutamine level by deamidating glutamine to glutamate and ammonia. Emerging data have provided evidence that several types of neoplastic cells require glutamine for the synthesis of proteins, nucleic acids, and lipids. This fundamental role of glutamine and its metabolic pathways for growth and proliferation of individual malignant cells may identify a special group of patients whose solid or hematologic neoplasms may benefit significantly from interruption of glutamine metabolism. To this end, asparaginase products deserve a second look particularly in non-ALL malignant blood disorders. Here, we review mechanisms of anti-tumor activity of asparaginase focusing on importance of glutamine reduction, pharmacology of asparaginase products, in vitro activities as well as clinical experience of incorporating asparaginase in therapeutic regimens for non-ALL hematologic malignancies.

Survival of adults with acute lymphoblastic leukemia in Germany and the United States

BACKGROUND

Adulthood acute lymphoblastic leukemia (ALL) is a rare disease. In contrast to childhood ALL, survival for adults with ALL is poor. Recently, new protocols, including use of pediatric protocols in young adults, have improved survival in clinical trials. Here, we examine population level survival in Germany and the United States (US) to gain insight into the extent to which changes in clinical trials have translated into better survival on the population level.

METHODS

Data were extracted from the Surveillance, Epidemiology, and End Results database in the US and 11 cancer registries in Germany. Patients age 15-69 diagnosed with ALL were included. Period analysis was used to estimate 5-year relative survival (RS).

RESULTS

Overall 5-year RS was estimated at 43.4% for Germany and 35.5% for the US (p = 0.004), with a decrease in survival with increasing age. Survival was higher in Germany than the US for men (43.6% versus 37.7%, p = 0.002) but not for women (42.4% versus 40.3%, p>0.1). Five-year RS estimates increased in Germany and the US between 2002 and 2006 by 11.8 and 7.3 percent units, respectively (p = 0.02 and 0.04, respectively).

CONCLUSIONS

Survival for adults with ALL continues to be low compared with that for children, but a substantial increase in 5-year survival estimates was seen from 2002 to 2006 in both Germany and the US. The reasons for the survival differences between both countries require clarification.

Cancer survival and excess mortality estimates among adolescents and young adults in Western Australia, 1982-2004: a population-based study

BACKGROUND

Data are limited on cancer outcomes in adolescents and young adults.

METHODS

Based on data from the Western Australian Data Linkage System, this study modelled survival and excess mortality in all adolescents and young adults aged 15-39 years in Western Australia who had a diagnosis of cancer in the period 1982-2004. Relative survival and excess all-cause mortality for all cancers combined and for principal tumour subgroups were estimated, using the Ederer II method and generalised linear Poisson modelling, respectively.

RESULTS

A cancer diagnosis in adolescents and young adults conferred substantial survival decrement. However, overall outcomes improved over calendar period (excess mortality hazard ratio [HR], latest versus earliest diagnostic period: 0.52, trend p<0.0001). Case fatality varied according to age group (HR, oldest versus youngest: 1.38, trend p<0.0001), sex (HR, female versus male: 0.66, 95% confidence interval [CI] 0.62-0.71), ethnicity (HR, Aboriginal versus others: 1.47, CI 1.23-1.76), geographical area (HR, rural/remote versus urban: 1.13, CI 1.04-1.23) and residential socioeconomic status (HR, lowest versus highest quartile: 1.14, trend p<0.05). Tumour subgroups differed substantially in frequency according to age group and sex, and were critical outcome determinants.

CONCLUSIONS

Marked progressive calendar-time improvement in overall outcomes was evident. Further research is required to disentangle the contributions of tumour biology and health service factors to outcome disparities between ethno-demographic, geographic and socioeconomic subgroups of adolescents and young adults with cancer.

Outcome of modified St Jude total therapy 13A for childhood acute lymphoblastic leukemia in the southeast region of Turkey

OBJECTIVE

To fill the gap in the current data on childhood acute lymphoblastic leukemia (ALL) in low-income and middle-income countries.

METHODS

This study included 106 children between the ages of 1 and 17 years with newly diagnosed ALL monitored between 1999 and 2010. All the patients were treated with the modified St Jude Total 13A treatment plan at the Pediatric Hematology Clinic at Harran University.

RESULTS

Sixty-eight (64.2%) patients were boys and 38 (35.8%) were girls. The median age at diagnosis was 5.9 ± 3.7 years. Thirty-eight (35.8%) children were classified as standard risk, 53 (39.3%) were intermediate risk, and 15 (14.2%) were high risk. Thirteen (12.3%) children died in induction before the remission date (43 d of remission induction). Of all the 93 (100%) patients who completed remission induction therapy and whose bone marrow were in remission, 5 (4.7%) had a bone marrow relapse, 1 (0.9%) had a retinal relapse, and 5 (4.7%) had secondary acute myeloid leukemia. At a median follow-up of 44 months (range, 0.36 to 135.5 mo), the estimated 5-year overall survival and event-free survival were 77.4 ± 5% and 68.9 ± 6.5%, respectively. The estimated 5-year overall survival for boys and girls was 76.5 ± 6% and 65.8 ± 8%, respectively (P = 0.182).

CONCLUSIONS

St Jude Total 13A treatment protocols to treat childhood ALL can be successfully adapted, which suggests that such an approach may be useful in low socioeconomic regions; however, it should be noted that secondary leukemia can occur at a high rate.

Sex variability in pediatric leukemia survival: large cohort evidence

Purpose. Sex disparities in pediatric leukemia have been previously reported, and male children continue to present with poorer survival. However, the observed disparities are not fully understood. This current study sought to examine disparities in survival by the sex, and to determine if tumor prognostic factors impact on these disparities. Patients and Methods. We used the Surveillance Epidemiology and End Results dataset of pediatric leukemia patients (ages 0–19 years) diagnosed in the United States from 1973 to 2006. There were 15,215 patients of whom 8,622 (65.7%) were boys and 6,593 (43.3%) were girls. The Kaplan-Meier survival estimates, log rank test, and Cox proportional hazard methods were used to assess the data. Results. The overall (both sexes) five-year survival rate was 67.9%. Girls had a survival rate of 70.1%, while the rate was 66.3% in boys. Girls had a significant 14% decreased risk of dying relative to boys, hazard ratio (HR) = 0.86, 99% CI = 0.80–0.93. There were significant differences between boys and girls with respect to tumor cell type, race, age at diagnosis, year of diagnosis, and number of primaries, P < 0.001. After controlling for these factors, the sex differences in survival persisted, with girls still less likely to die from leukemia compared to boys, adjusted HR (AHR) = 0.85, 99% CI = 0.72–1.00, P < 0.01. Conclusion. In a large population-based pediatric leukemia study, boys continued to show poorer survival. These disparities were not completely explained by treatment received, tumor prognostic or socio-demographic factors.

Challenges in implementing individualized medicine illustrated by antimetabolite therapy of childhood acute lymphoblastic leukemia

Predicting the response to medical therapy and subsequently individualizing the treatment to increase efficacy or reduce toxicity has been a longstanding clinical goal. Not least within oncology, where many patients fail to be cured, and others are treated to or beyond the limit of acceptable toxicity, an individualized therapeutic approach is indicated. The mapping of the human genome and technological developments in DNA sequencing, gene expression profiling, and proteomics have raised the expectations for implementing genotype-phenotype data into the clinical decision process, but also multiplied the complex interaction of genetic and other laboratory parameters that can be used for therapy adjustments. Thus, with the advances in the laboratory techniques, post laboratory issues have become major obstacles for treatment individualization. Many of these challenges have been illustrated by studies involving childhood acute lymphoblastic leukemia (ALL), where each patient may receive up to 13 different anticancer agents over a period of 2-3 years. The challenges include i) addressing important, but low-frequency outcomes, ii) difficulties in interpreting the impact of single drug or single gene response data that often vary across treatment protocols, iii) combining disease and host genomics with outcome variations, and iv) physicians' reluctance in implementing potentially useful genotype and phenotype data into clinical practice, since unjustified downward or upward dose adjustments could increase the of risk of relapse or life-threatening complications. In this review we use childhood ALL therapy as a model and discuss these issues, and how they may be addressed.

Methotrexate pharmacokinetics in childhood acute lymphoblastic leukaemia: a prognostic value?

WHAT IS KNOWN AND OBJECTIVE

In industrialized countries, acute lymphoblastic leukaemia (ALL) is the most frequent cancer in children aged less than 15 years. High-dose methotrexate is a common component of many chemotherapeutic protocols for childhood with ALL. Our objective was to retrospectively evaluate the pharmacokinetics and plasma levels of high-dose methotrexate as it relates to event-free survival (EFS) in children with ALL.

METHODS

Relapsed patients and subjects in EFS were compared for MTX serum concentrations 24, 36, 48 and 72 h after the start of 24 h infusion. Clearance (Cl), area under the curve (AUC) and volume of distribution (V(d) ) of the drug were estimated by the NONMEM computer program and also compared between both groups.

RESULTS AND DISCUSSION

Among 69 children included, 54 (78·3%) were still in EFS, whereas 15 (21·7%) relapsed. The difference between relapsed and EFS patients for the pharmacokinetic parameters studied was not significant. On the contrary, the cohort studied was representative and known prognostic factors for relapse in ALL were significantly associated with relapse.

WHAT IS NEW AND CONCLUSION

Serum concentrations and pharmacokinetic parameters of MTX are not associated with outcome in ALL. Prognoses based on single-drug pharmacokinetic estimates within a complex multiple-agent protocol appear to be unreliable. However, therapeutic drug monitoring of high-dose methotrexate remains a useful tool for early detection of impaired elimination and for avoiding systemic toxicity.

Assessment of dexrazoxane as a cardioprotectant in doxorubicin-treated children with high-risk acute lymphoblastic leukaemia: long-term follow-up of a prospective, randomised, multicentre trial

BACKGROUND

Doxorubicin chemotherapy is associated with cardiomyopathy. Dexrazoxane reduces cardiac damage during treatment with doxorubicin in children with acute lymphoblastic leukaemia (ALL). We aimed to establish the long-term effect of dexrazoxane on the subclinical state of cardiac health in survivors of childhood high-risk ALL 5 years after completion of doxorubicin treatment.

METHODS

Between January, 1996, and September, 2000, children with high-risk ALL were enrolled from nine centres in the USA, Canada, and Puerto Rico. Patients were assigned by block randomisation to receive ten doses of 30 mg/m² doxorubicin alone or the same dose of doxorubicin preceded by 300 mg/m² dexrazoxane. Treatment assignment was obtained through a telephone call to a centralised registrar to conceal allocation. Investigators were masked to treatment assignment but treating physicians and patients were not; however, investigators, physicians, and patients were masked to study serum cardiac troponin-T concentrations and echocardiographic measurements. The primary endpoints were late left ventricular structure and function abnormalities as assessed by echocardiography; analyses were done including all patients with data available after treatment completion. This trial has been completed and is registered with ClinicalTrials.gov, number NCT00165087.

FINDINGS

100 children were assigned to doxorubicin (66 analysed) and 105 to doxorubicin plus dexrazoxane (68 analysed). 5 years after the completion of doxorubicin chemotherapy, mean left ventricular fractional shortening and end-systolic dimension Z scores were significantly worse than normal for children who received doxorubicin alone (left ventricular fractional shortening: -0·82, 95% CI -1·31 to -0·33; end-systolic dimension: 0·57, 0·21-0·93) but not for those who also received dexrazoxane (-0·41, -0·88 to 0·06; 0·15, -0·20 to 0·51). The protective effect of dexrazoxane, relative to doxorubicin alone, on left ventricular wall thickness (difference between groups: 0·47, 0·46-0·48) and thickness-to-dimension ratio (0·66, 0·64-0·68) were the only statistically significant characteristics at 5 years. Subgroup analysis showed dexrazoxane protection (p=0·04) for left ventricular fractional shortening at 5 years in girls (1·17, 0·24-2·11), but not in boys (-0·10, -0·87 to 0·68). Similarly, subgroup analysis showed dexrazoxane protection (p=0·046) for the left ventricular thickness-to-dimension ratio at 5 years in girls (1·15, 0·44-1·85), but not in boys (0·19, -0·42 to 0·81). With a median follow-up for recurrence and death of 8·7 years (range 1·3-12·1), event-free survival was 77% (95% CI 67-84) for children in the doxorubicin-alone group, and 76% (67-84) for children in the doxorubicin plus dexrazoxane group (p=0·99).

INTERPRETATION

Dexrazoxane provides long-term cardioprotection without compromising oncological efficacy in doxorubicin-treated children with high-risk ALL. Dexrazoxane exerts greater long-term cardioprotective effects in girls than in boys.

FUNDING

US National Institutes of Health, Children's Cardiomyopathy Foundation, University of Miami Women's Cancer Association, Lance Armstrong Foundation, Roche Diagnostics, Pfizer, and Novartis.

Childhood cancer survival: a report from the United Kingdom Childhood Cancer Study

BACKGROUND

Improvements in diagnostic approaches and refinements to treatment protocols have resulted in 5-year survival levels above 70% for children diagnosed with cancer in economically developed parts of the world. For some cancers, including leukaemia and tumours of the central nervous system, age and sex have been identified as important prognostic indicators.

METHODS

We examined long-term survival, and affects of age and sex, in a population-based case-control study. Children (0-14 years) newly diagnosed with cancer were ascertained between 1991 and 1996 (n=4433). Follow-up information was obtained from the National Health Service (NHS) Information Centre for Health and Social Care which records all exits from the NHS including deaths.

RESULTS

For all cancer diagnoses combined, 5-year survival was 72.7% dropping to 67.9% at 15 years. As expected, survival differed between diagnostic subtypes ranging from 38.1% for intracranial embryonal tumours to 96.2% for Hodgkin lymphoma. Compared to girls, boys diagnosed with acute lymphoblastic leukaemia were at a higher risk of dying (RR=1.26, 95% CI 1.03-1.53), whereas boys diagnosed with an intracranial embryonal tumour were at a lower risk of death (RR=0.63, 95% CI 0.43-0.91).

CONCLUSION

Our initial findings are consistent with previous reports, and highlight the importance of considering differences by age and sex. The completeness and population-based nature of the original case-control study is an important feature which will provide the basis for future more detailed investigations linking disease determinants to outcome.

Prognostic factors in adult acute lymphoblastic leukaemia

Treatment of acute lymphoblastic leukaemia (ALL) in adults presents a formidable challenge. While overall results have improved over the past 3 decades, the long-term survival for patients aged less than 60 years is only in the range of 30-40% and is 10-15% if between 60 and 70 years and <5% for those over 70 years. The historic lack of clear-cut biological prognostic factors has led to over- or under-treatment of some patients. Response to initial therapy is an important prognosticator of outcome based on disease biology, as well as pharmacogenetics, which include the patient's response to drugs given. The more widespread availability of allogeneic transplantation and reduced-intensity regimens for older patients have opened up this curative modality to a greater number of patients. Hopefully, those options, as well as novel cytogenetic and molecular markers, will enable a better selection of patients who undergo intensive therapies and finally break the 30-40% cure barrier for adults with ALL.

Benefits of the Intermittent Use of 6-Mercaptopurine and Methotrexate in Maintenance Treatment for Low-Risk Acute Lymphoblastic Leukemia in Children: Randomized Trial From the Brazilian Childhood Cooperative Group—Protocol ALL-99

Purpose

To describe event-free survival (EFS) and toxicities in children with low-risk acute lymphoblastic leukemia (ALL) assigned to receive either continuous 6-mercaptopurine (6-MP) and weekly methotrexate (MTX) or intermittent 6-MP with intermediate-dose MTX, as maintenance treatment.

Patients and Methods

Between October 1, 2000, and December 31, 2007, 635 patients with low-risk ALL were enrolled onto Brazilian Childhood Cooperative Group for ALL Treatment (GBTLI) ALL-99 protocol. Eligible children (n = 544) were randomly allocated to receive either continuous 6-MP/MTX (group 1, n = 272) or intermittent 6-MP (100 mg/m2/d for 10 days, with 11 days resting) and MTX (200 mg/m2every 3 weeks; group 2, n = 272).

Results

The 5-year overall survival (OS) and EFS were 92.5% ± 1.5% SE and 83.6% ± 2.1% SE, respectively. According to maintenance regimen, the OS was 91.4% ± 2.2% SE (group 1) and 93.6% ± 2.1% SE (group 2; P = .28) and EFS 80.9% ± 3.2% SE (group 1) and 86.5% ± 2.8% SE (group 2; P = .089). Remarkably, the intermittent regimen led to significantly higher EFS among boys (85.7% v 74.9% SE; P = .027), while no difference was seen for girls (87.0% v 88.8% SE; P = .78). Toxic episodes were recorded in 226 and 237 children, respectively. Grade 3 to 4 toxic events for groups 1 and 2 were, respectively, 273 and 166 for hepatic dysfunction (P = .002), and 772 and 636 for hematologic episodes (P = .005). Deaths on maintenance were: seven (group 1) and one (group 2).

Conclusion

The intermittent use of 6-MP and MTX in maintenance is a less toxic regimen, with a trend toward better long-term EFS. Boys treated with the intermittent schedule had significantly better EFS.

Oral 6-mercaptopurine versus oral 6-thioguanine and veno-occlusive disease in children with standard-risk acute lymphoblastic leukemia: report of the Children's Oncology Group CCG-1952 clinical trial

The Children's Cancer Group 1952 (CCG-1952) clinical trial studied the substitution of oral 6-thioguanine (TG) for 6-mercaptopurine (MP) and triple intrathecal therapy (ITT) for intrathecal methotrexate (IT-MTX) in the treatment of standard-risk acute lymphoblastic leukemia. After remission induction, 2027 patients were randomized to receive MP (n = 1010) or TG (n = 1017) and IT-MTX (n = 1018) or ITT (n = 1009). The results of the thiopurine comparison are as follows. The estimated 7-year event-free survival (EFS) for subjects randomized to TG was 84.1% (+/- 1.8%) and to MP was 79.0% (+/- 2.1%; P = .004 log rank), although overall survival was 91.9% (+/- 1.4%) and 91.2% (+/- 1.5%), respectively (P = .6 log rank). The TG starting dose was reduced from 60 to 50 mg/m(2) per day after recognition of hepatic veno-occlusive disease (VOD). A total of 257 patients on TG (25%) developed VOD or disproportionate thrombocytopenia and switched to MP. Once portal hypertension occurred, all subjects on TG were changed to MP. The benefit of randomization to TG over MP, as measured by EFS, was evident primarily in boys who began TG at 60 mg/m(2) (relative hazard rate [RHR] 0.65, P = .002). The toxicities of TG preclude its protracted use as given in this study. This study is registered at http://clinicaltrials.gov as NCT00002744.

Gender Differences in Incidence Rates of Childhood B-Precursor Acute Lymphocytic Leukemia in Mississippi

The authors studied pediatric patients with B-precursor acute lymphocytic leukemia (ALL) to determine whether Mississippi’s gender incidences correlate with national statistics. Furthermore, data on gender incidences in each of the risk categories of low, standard, and high were collected. A retrospective chart review was performed of pediatric B-precursor ALL patients diagnosed at the Children’s Cancer Clinic at the University of Mississippi Medical Center from 1995 to 2005. The gender incidences in Mississippi were found to be comparable with the national average for ALL (1.34:1 vs 1.3:1) overall. However, the national average includes T-cell ALL, which is known to be significantly more prevalent in boys. Of greater significance, boys were noted to present with high-risk B-precursor ALL 4 times more than girls, suggesting the need for further investigation into possible causes of this phenomenon.

Oral 6-mercaptopurine versus oral 6-thioguanine and veno-occlusive disease in children with standard-risk acute lymphoblastic leukemia: report of the Children's Oncology Group CCG-1952 clinical trial

The Children's Cancer Group 1952 (CCG-1952) clinical trial studied the substitution of oral 6-thioguanine (TG) for 6-mercaptopurine (MP) and triple intrathecal therapy (ITT) for intrathecal methotrexate (IT-MTX) in the treatment of standard-risk acute lymphoblastic leukemia. After remission induction, 2027 patients were randomized to receive MP (n = 1010) or TG (n = 1017) and IT-MTX (n = 1018) or ITT (n = 1009). The results of the thiopurine comparison are as follows. The estimated 7-year event-free survival (EFS) for subjects randomized to TG was 84.1% (+/- 1.8%) and to MP was 79.0% (+/- 2.1%; P = .004 log rank), although overall survival was 91.9% (+/- 1.4%) and 91.2% (+/- 1.5%), respectively (P = .6 log rank). The TG starting dose was reduced from 60 to 50 mg/m(2) per day after recognition of hepatic veno-occlusive disease (VOD). A total of 257 patients on TG (25%) developed VOD or disproportionate thrombocytopenia and switched to MP. Once portal hypertension occurred, all subjects on TG were changed to MP. The benefit of randomization to TG over MP, as measured by EFS, was evident primarily in boys who began TG at 60 mg/m(2) (relative hazard rate [RHR] 0.65, P = .002). The toxicities of TG preclude its protracted use as given in this study. This study is registered at http://clinicaltrials.gov as NCT00002744.

Long-term results of Tokyo Children's Cancer Study Group trials for childhood acute lymphoblastic leukemia, 1984-1999

We report the long-term results of Tokyo Children's Cancer Study Group's studies L84-11, L89-12, L92-13, and L95-14 for 1846 children with acute lymphoblastic leukemia, which were conducted between 1984 and 1999. The value of event-free survival (EFS)+/-s.e. was 67.2+/-2.2% at 10 years in L84-11, which was not improved in the following two studies, and eventually improved to 75.0+/-1.8% at 10 years in L95-14 study. The lower EFS of the L89-12 reflected a high rate of induction failure because of infection and delayed remission in very high-risk patients. The L92-13 study was characterized by short maintenance therapy; it resulted in poor EFS, particularly in the standard-risk (SR) group and boys. Females did significantly better than males in EFS in the early three studies. The gender difference was not significant in overall survival, partly because >60% of the males survived after the testicular relapse. Randomized studies in the former three protocols revealed that intermediate- or high-dose methotrexate therapy significantly reduced the testicular relapse rate. In the L95-14 study, gender difference disappeared in EFS. Contrary to the results of larger-scale studies, the randomized control study in the L95-14 reconfirmed with updated data that dexamethasone 8 mg/m(2) had no advantage over prednisolone 60 mg/m(2) in the SR and intermediate-risk groups. Prophylactic cranial irradiation was assigned to 100, 80, 44, and 44% of the patients in the studies, respectively. Isolated central nervous system relapse rates decreased to <2% in the last two trials. Secondary brain tumors developed in 12 patients at 8-22 years after cranial irradiation. Improvement of the remission induction rates and the complete omission of irradiation are currently main objectives in our studies.

Immunohistochemical and other prognostic factors in B cell non Hodgkin lymphoma patients, Kampala, Uganda

BACKGROUND

Non Hodgkin lymphomas are the most common lymphomas in Uganda. Recent studies from developed countries have shown differences in survival for the different immunophenotypes. Such studies are lacking in Africa where diagnosis is largely dependent on morphology alone. We report immunohistochemical and other prognostic factors in B cell non Hodgkin lymphoma patients in Kampala, Uganda.

METHODS

Non Hodgkin lymphoma tissue blocks from the archives of the Department of Pathology, Makerere University College of Health Sciences, Kampala, Uganda, from 1991-2000, were sub typed using haematoxylin and eosin, Giemsa as well as immunohistochemistry. Using tissue micro array, 119 biopsies were subjected to: CD3, CD5, CD10, CD20, CD23, CD30, CD38, CD79a, CD138, Bcl-6, Bcl-2, IRTA-1, MUM1/IRF4, Bcl-1/cyclin D1, TdT, ALKc, and Ki-67/Mib1. Case notes were retrieved for: disease stage, chemotherapy courses received and retrospective follow up was done for survival.

RESULTS

Non Hodgkin B cell lymphomas comprised of Burkitt lymphoma [BL] (95/119) diffuse large B cell lymphoma (19/119), mantle cell lymphoma (4/119) and precursor B lymphoblastic lymphoma (1/119). For Burkitt lymphoma, good prognosis was associated with receiving chemotherapy, female gender and CD30 positivity. Only receiving chemotherapy remained significant after Cox regression analysis. Diffuse large B cell lymphomas with activated germinal centre B cell (GCB) pattern (CD10+/-, BCL-6+/-, MUM+/-, CD138+/-) had better survival (98.4 months; 95% CI 89.5 -107.3) than the others (57.3 months; 95% CI 35.5 - 79.0) p = 0.027 (log rank test).

CONCLUSIONS

Activated GCB diffuse large B cell lymphoma had a better prognosis than the others. For Burkitt lymphoma, not receiving chemotherapy carried a poor prognosis. Availability of chemotherapy in this resource limited setting is critical for survival of lymphoma patients.

Elevated mRNA level of hST6Gal I and hST3Gal V positively correlates with the high risk of pediatric acute leukemia

Altered sialylation occurs in essentially all types of human and experimental cancers. Although, aberrant sialylation is believed to mainly due to altered sialyltransferase (ST) level, so far, expression pattern of different STs in acute lymphoblastic leukemia has never been investigated. Accordingly, the aim of our study was to monitor the changes in mRNA expression of ST6Gal I, ST3Gal V and ST8Sia I in patients by real-time PCR, which may provide prognostic information useful in defining appropriate therapeutic options. Our data demonstrated that ST6Gal I and ST3Gal V mRNA were up-regulated in lymphoblasts whereas its presence was negligible in non-malignant donors. In contrast, ST8SiaI was downregulated in patients. The extents of linkage-specific sialylation of glycoconjugates were found to be associated with disease establishment. Additionally, ST6Gal I and ST3Gal V were positively correlated with the high risk of the disease (P=0.0032 and 0.0016). This differential ST level can be used as biomarker with the molecular method of quantitative PCR and may be useful to discriminate normal and cancer patients.

Detection of submicroscopic disease in the bone marrow and unaffected testis of a child with T-cell acute lymphoblastic leukemia who experienced "isolated" testicular relapse

Testicular relapse has an impact on the prognosis of boys with acute lymphoblastic leukemia (ALL). Because isolated testicular relapse often precedes hematological relapse, systemic therapy is required in addition to local therapy. However, a rationale for the use of a combination of systemic chemotherapy and local therapy is unclear. A 12-year-old boy with T-ALL suffered from isolated testicular relapse at 27 months after diagnosis. He was successfully treated with systemic chemotherapy with orchiectomy and prophylactic irradiation to the contralateral testis. We retrospectively estimated the minimal residual disease in the bone marrow (BM) and the testis by detection of clone-specific T-cell receptor rearrangement of leukemic cells. We detected leukemic cells in the affected testis at relapse, as well as in the BM at initial diagnosis. In addition, we confirmed submicroscopic disease in the unaffected testis and the BM at relapse. We conclude that molecular analysis could reveal the submicroscopic disease in the patient with apparently isolated testicular relapse. This finding may provide a rationale for intensified systemic treatment of patients with isolated testicular relapse.

P-glycoprotein activity predicts outcome in childhood acute lymphoblastic leukemia

Treatment of children with acute lymphoblastic leukemia (ALL) is based on P-glycoprotein (P-gp)-dependent cytostatics. We assessed the P-gp function in blast cells as a possible prognostic factor and its influence on the overall survival. P-gp function was measured using the verapamil-sensitive Rhodamine efflux. Cell samples from 7 of 45 (16%) patients revealed rhodamine-efflux positive blasts. There were no relations between the presence of P-gp, clinical characteristics (age, sex, hepatomegaly, and splenomegaly) and initial laboratory parameters (immunophenotype, white blood cells count, and serum lactate dehydrogenase) in ALL. P-gp activity plays a negative role, both for a remission achieved on day 33 and for susceptibility to steroid therapy. Children bearing rhodamine-efflux positive blasts had a significantly shorter 5-year overall survival of 35%, as compared with 74% in those negative for P-gp function. Lack of any association with clinical characteristic and initial laboratory parameters suggests that presence of P-gp is an independent prognostic factor.

Risk-adapted treatment of acute promyelocytic leukemia with all-trans retinoic acid and anthracycline monochemotherapy: long-term outcome of the LPA 99 multicenter study by the PETHEMA Group

A previous report of the Programa de Estudio y Tratamiento de las Hemopatías Malignas (PETHEMA) Group showed that a risk-adapted strategy combining all-trans retinoic acid (ATRA) and anthracycline monochemotherapy for induction and consolidation in newly diagnosed acute promyelocytic leukemia results in an improved outcome. Here we analyze treatment outcome of an enlarged series of patients who have been followed up for a median of 65 months. From November 1999 through July 2005 (LPA99 trial), 560 patients received induction therapy with ATRA plus idarubicin. Patients achieving complete remission received 3 courses of consolidation followed by maintenance with ATRA and low-dose chemotherapy. The 5-year cumulative incidence of relapse and disease-free survival were 11% and 84%, respectively. These results compare favorably with those obtained in the previous LPA96 study (P = .019 and P = .04, respectively). This updated analysis confirms the high antileukemic efficacy, low toxicity, and high degree of compliance of a risk-adapted strategy combining ATRA and anthracycline monochemotherapy for consolidation therapy.

Risk-adjusted therapy of acute lymphoblastic leukemia can decrease treatment burden and improve survival: treatment results of 2169 unselected pediatric and adolescent patients enrolled in the trial ALL-BFM 95

The trial ALL-BFM 95 for treatment of childhood acute lymphoblastic leukemia was designed to reduce acute and long-term toxicity in selected patient groups with favorable prognosis and to improve outcome in poor-risk groups by treatment intensification. These aims were pursued through a stratification strategy using white blood cell count, age, immunophenotype, treatment response, and unfavorable genetic aberrations providing an excellent discrimination of risk groups. Estimated 6-year event-free survival (6y-pEFS) for all 2169 patients was 79.6% (+/- 0.9%). The large standard-risk (SR) group (35% of patients) achieved an excellent 6y-EFS of 89.5% (+/- 1.1%) despite significant reduction of anthracyclines. In the medium-risk (MR) group (53% of patients), 6y-pEFS was 79.7% (+/- 1.2%); no improvement was accomplished by the randomized use of additional intermediate-dose cytarabine after consolidation. Omission of preventive cranial irradiation in non-T-ALL MR patients was possible without significant reduction of EFS, although the incidence of central nervous system relapses increased. In the high-risk (HR) group (12% of patients), intensification of consolidation/reinduction treatment led to considerable improvement over the previous ALL-BFM trials yielding a 6y-pEFS of 49.2% (+/- 3.2%). Compared without previous trial ALL-BFM 90, consistently favorable results in non-HR patients were achieved with significant treatment reduction in the majority of these patients.

Antimetabolite therapy for lesser-risk B-lineage acute lymphoblastic leukemia of childhood: a report from Children's Oncology Group Study P9201

Pediatric Oncology Group (POG) protocol 9201 enrolled children with lesser-risk B-lineage acute lymphoblastic leukemia (ALL) defined by age (1-9), white blood cell count (WBC) less than 50 x 10(9)/L (50,000/microL), DNA findings of trisomies 4 and 10 (or DNA index > 1.16), and lack of overt central nervous system (CNS) leukemia. After vincristine, prednisone, and asparaginase induction, 650 of 653 eligible patients attained remission (3 induction deaths) and received 6 courses of intravenous methotrexate (1 g/m(2)) with daily mercaptopurine. Weekly intramuscular methotrexate was added during maintenance; pulses of vincristine and prednisone were administered with periodic intrathecal chemotherapy. Treatment duration was 2.5 years. No alkylators, epipodophylotoxins, anthracyclines, or radiation were given. The 6-year event-free survival (EFS) was 86.6% with overall survival (OS) of 97.2%. Patients with less than 5% marrow blasts on induction day 15 had superior EFS. A difference not reaching conventional statistical significance (P = .068) was noted for superior outcomes in patients with trisomies of chromosomes 4 and 10 versus those lacking double trisomies. Sex, ethnicity, CNS status, and WBC were not predictive. This indicates the great majority of children with lesser-risk B-lineage ALL are curable without agents with substantial late effects.

Immunologic profile and outcome of childhood acute lymphoblastic leukemia (ALL) in Morocco

Immunophenotyping in leukemia offers a precise delineation of the hematopoietic lineage and differentiation stage of the malignant cell. In this study, we used flow cytometry to determine the frequency of the immunologic types of acute lymphoblastic leukemia (ALL) in Moroccan children. We analyzed 100 samples from ALL patients within an age ranging from 6 months to 16 years presented over a 4-year period (1996 to 2000). Immunophenotyping allowed classification into 2 major categories: T-ALL (37%) and B-ALL (63%), with a higher percentage of males (69%). Comparison of the clinical characteristics showed that the frequency of splenomegaly was similar in B-ALL and T-ALL patients (53% and 47%, respectively). Hepatomegaly and mediastinal masses were more often associated with T-ALL (62% and 71%, respectively). Splenomegaly, hepatomegaly, and mediastinal masses were more frequent in immature than mature B-ALL, whereas the reverse was observed for T-ALL. Complete remission was obtained in 88% and 84% of B-ALL and T-ALL, respectively and relapse after 1 year occurred in 30% and 37% of cases, respectively. CD10 expressing B-ALL showed a slightly higher complete remission rate, whereas the reverse was observed for CD10 expressing T-ALL. The overall 5-year survival rate of ALL was 38%, whereas patients with B-ALL showed better survival than children with T-ALL.