Margarita Baka

In vitro fertilization and risk of childhood leukemia in Greece and Sweden.

Cancer risk in children born after in vitro fertilization (IVF) remains largely unknown. We aimed to investigate risk of leukemia and lymphoma following IVF using two nationwide datasets.

Fetal growth and childhood acute lymphoblastic leukemia: findings from the childhood leukemia international consortium.

Positive associations have been reported between the measures of accelerated fetal growth and risk of childhood acute lymphoblastic leukemia (ALL). We investigated this association by pooling individual‐level data from 12 case–control studies participating in the Childhood Leukemia International Consortium. Two measures of fetal growth—weight‐for‐gestational‐age and proportion of optimal birth weight (POBW)—were analysed. Study‐specific odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, and combined in fixed effects meta‐analyses. Pooled analyses of all data were also undertaken using multivariable logistic regression. Subgroup analyses were undertaken when possible. Data on weight for gestational age were available for 7,348 cases and 12,489 controls from all 12 studies and POBW data were available for 1,680 cases and 3,139 controls from three studies. The summary ORs from the meta‐analyses were 1.24 (95% CI: 1.13, 1.36) for children who were large for gestational age relative to appropriate for gestational age, and 1.16 (95% CI: 1.09, 1.24) for a one‐standard deviation increase in POBW. The pooled analyses produced similar results. The summary and pooled ORs for small‐for‐gestational‐age children were 0.83 (95% CI: 0.75, 0.92) and 0.86 (95% CI: 0.77, 0.95), respectively. Results were consistent across subgroups defined by sex, ethnicity and immunophenotype, and when the analysis was restricted to children who did not have high birth weight. The evidence that accelerated fetal growth is associated with a modest increased risk of childhood ALL is strong and consistent with known biological mechanisms involving insulin‐like growth factors.

Longitudinal assessment of immunological status and rate of immune recovery following treatment in children with ALL

We prospectively evaluated the immunological status, immune recovery and risk of infection in pediatric ALL patients treated on the BFM 95 protocol.

Maternal smoking during pregnancy and risk for childhood leukemia: A nationwide case–control study in Greece and meta-analysis†

Maternal smoking during pregnancy has been often implicated in the development of childhood leukemia with ambiguous results. Hence, we conducted a meta‐analysis aiming to summarize current evidence and quantify any tentative impact.

An integrated evaluation of socioeconomic and clinical factors in the survival from childhood acute lymphoblastic leukaemia: a study in Greece.

An evaluation of the role of socioeconomic factors in the survival of children with leukaemia, controlling for major clinical prognostic indicators, has been attempted in very few studies and the role of these factors may be different in various cultural settings. Our investigation aims to study the independent role of socioeconomic factors on the prognosis of childhood acute lymphoblastic leukaemia (ALL) in Greece. During a 7-year period (1996–2002) 293 cases of incident ALL were diagnosed and followed up in four Childhood Haematology-Oncology Units, which covered over half of all childhood ALL cases nationwide. At the time of diagnosis, information concerning age, gender, maternal schooling, maternal marital status, sibship size, distance of residence from the treating centre, attendance of day care centre and clinical information was recorded. The influence of these factors on survival was studied by modelling the data through Coxs proportional-hazards regression. After adjustment for clinical prognostic factors, children of mothers who were not currently married, were of low educational level or were living far from the treating centre tended to have lower survival (P-values 0.02, 0.14 and 0.08, respectively). There was also evidence that two factors that are predictive of disease occurrence, that is sibship size and attendance of day care centre, may also predict survival (P-values 0.04 and 0.26, respectively). In conclusion, socioeconomic factors are likely to influence survival from ALL at least in some sociocultural contexts. Moreover, there is evidence that factors that could affect incidence of ALL through modulation of herd immunity may also have prognostic implications for this disease.

Allergy and risk of acute lymphoblastic leukemia among children: A nationwide case control study in Greece

BACKGROUND Several reports point to inverse associations between allergies and ALL; yet, no study has explored this link using both self-reported-data on allergic history and biomarkers of atopic sensitization. METHODS Clinical information for the variables of interest was available for 252 out of 292 cases of childhood (0-14 years) ALL, newly diagnosed across Greece over a 4.5 year period as well as for 294 hospital controls. Allergen-specific-IgEs, as markers of allergic predisposition, against 24 most prevalent respiratory and food allergens, were determined, using an enzyme immunoassay procedure for 199 children with ALL and 113 controls. Cases were compared with controls through frequency distributions and unconditional multiple logistic regression models to estimate odds ratios (ORs) and 95% confidence-intervals (CIs) regarding associations of allergy with childhood ALL. RESULTS Self-reported-allergic history overall (OR: 0.49, 95% CI: 0.34-0.72) and practically each one of its main components (respiratory, food, any other clinical allergy) were strongly and inversely associated with ALL. Likewise, the serum IgE inverse association was of the same magnitude (OR: 0.43, 95% CI: 0.22-0.84) mainly contributed by food IgE (OR: 0.39, 95% CI: 0.18-0.83). CONCLUSION Beyond the already established inverse association of allergic history with childhood ALL, a same magnitude association is evident when serologic markers of allergic predisposition are used as an alternative measure of allergy. Further research with more appropriate study designs is needed to better understand possible associations between prior allergy and childhood ALL risk.

Socioeconomic status, area remoteness, and survival from childhood leukemia: results from the Nationwide Registry for Childhood Hematological Malignancies in Greece

The aim of the present nationwide Greek study is to assess whether survival from acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is modified by socioeconomic status (SES) and area remoteness. Detailed precoded information derived from a personal interview conducted by specially trained health personnel with the child guardians was available for 883 ALL and 111 AML incident childhood cases registered in the Nationwide Registry for Childhood Hematological Malignancies during the period 1996–2010. Parental socioprofessional category was recorded on the basis of ISCO68 and ISCO88 codes; the exact traveling distance between residence and the treating hospital was ad hoc calculated. Multivariate Cox’s proportional hazards models were applied to examine the mutually adjusted associations between survival and potential predictors. Children from a lower parental socioprofessional category experienced 40% worse survival (P=0.02) independent of age, sex, and ALL subtype, whereas those whose parents were married had better outcomes (rate ratio: 0.47, P=0.01). Urbanization of residence at diagnosis or ‘residence to treating hospital’ distance was not nominally associated with survival from ALL. By contrast, no noteworthy associations implicating SES were found for AML survival, probably because of the burden of the disease and small numbers. Lower SES indicators and a single-parenthood family milieu seem to be independently associated with unfavorable outcomes from childhood ALL. Area remoteness might not be a significant outcome predictor during recent years, following considerable improvements in the motorway infrastructures and care delivery patterns. This study may provide a valuable snapshot capturing the impact of socioeconomic covariates before the burst of the Greek financial crisis.

Prelabor cesarean delivery and early-onset acute childhood leukemia risk.

The long-term impact of cesarean delivery (CD) on the health of the offspring is being explored methodically. We sought to investigate the effect of birth by (a) prelabor and (b) during-labor CD on the risk of early-onset (⩽3 years) acute lymphoblastic leukemia (ALL), specifically of its prevailing precursor B (B-ALL) subtype. A total of 1099 incident cases of ALL (957 B-ALL), 131 of acute myeloid leukemia (AML), and their 1 : 1 age-matched and sex-matched controls, derived from the Nationwide Registry for Childhood Hematological Malignancies (1996–2013), were analyzed using multivariate regression models. A null association was found between prelabor and/or during labor CD and either ALL (B-ALL) or AML in the 0–14 age range. By contrast, birth by CD increased significantly the risk of early-onset ALL [odds ratioCD (ORCD)=1.57, 95% confidence interval (CI): 1.10–2.24] mainly on account of prelabor CD (ORprelaborCD=1.66, 95% CI: 1.13–2.43). The respective figures were even higher for the early-onset precursor B-ALL (ORCD=1.66, 95% CI: 1.15–2.40 and ORprelaborCD=1.79, 95% CI: 1.21–2.66), whereas no association emerged for early-onset AML. Prelabor CD, which deprives exposure of the fetus/infant to the presumably beneficial effect of stress hormones released in both vaginal labor and during labor CD, was associated exclusively with an increased risk of early-onset ALL, particularly the precursor B-ALL subtype. If confirmed, these adverse long-term outcomes of CD may point to re-evaluation of prelabor CD practices and prompt scientific discussion on the best ways to simulate the effects of vaginal delivery, such as a precesarean induction of labor.

Differences Between Younger and Older Patients with Childhood Hodgkin Lymphoma

From 1979 to 2006, 74 children with Hodgkins lymphoma were treated at our center. Among them, 15 (14 boys and 1 girl) and 59 (33 boys and 26 girls) patients were younger and older than 8 years, respectively. Six (40%) children among younger patients and 26 (44%) among older patients had advanced stage disease. We detected 3 (20%) relapses among younger patients and 5 (8.5%) among the older patients. All of younger patients are alive whereas three of the older patients have died. Second malignancy developed in one and three children among younger and older patients, respectively. The only difference that was detected concerning the age was a male predominance among the younger patients.

Optic pathway glioma in children: 10 years of experience in a single institution

ABSTRACT Optic pathway glioma (OPG) is a rare brain tumor that occurs more commonly during early childhood and is frequently associated with neurofibromatosis type 1 (NF1). In this study, our aim was to describe the characteristics, management, and outcome of patients with OPG. We retrospectively analyzed the clinical charts of all children diagnosed with OPG at our institution from 2003 to 2013. Twenty children (11 boys and 9 girls, median age: 5 and 3/12 years; NF1: 15/20) were diagnosed with OPG. The diagnosis was based on magnetic resonance imaging (MRI) findings. A biopsy was useful in 3 patients. The main reason for seeking medical advice was decreased vision (7/20 patients), whereas in 10/20 patients, the diagnosis was established during the routine follow-up for their NF1. Fifteen patients demonstrated MRI findings of optic nerve involvement and/or chiasmal tumor, whereas in 5 children, postchiasmal structures were also involved. Sixteen patients (16/20) received carboplatin-based regimens, whereas 4/20 patients were only under close observation. Six patients showed deterioration of visual acuity and/or imaging findings at the end of treatment and/or during their follow-up. Three of them (3/6) underwent tumor resection, whereas 1 (1/6) received radiation treatment. None of our patients had total blindness from both eyes. Half of our patients were diagnosed during follow-up for their NF1, the incidence of which was high in our group. Our data suggest that chemotherapy helps in the preservation of vision in the majority of children.