Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study.

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.

Inequalities in diagnosis and registration of pediatric very rare tumors: a European study on pleuropulmonary blastoma.

Very rare tumors (VRTs) account for up to 11% of childhood cancers. Dedicated national groups and registries only exist in some European countries. Pleuropulmonary blastoma (PPB) is a very rare intrathoracic pediatric tumor with a potentially severe prognosis. Due to its rarity, it sometimes goes unrecognized. We investigated PPB diagnostic capability and possible correlations between diagnostic performance and VRT-dedicated activities. The number of cases of PPB registered between 2000 and 2014 at pediatric oncology centers in Europe was compared with the number of expected cases. Data sources included VRT registries, population-based cancer registries, and hospital registries. Data were obtained for 25 countries, grouped into 4 geographical regions. The expected cases were 111, and the observed cases were 129. The observed-to-expected ratio was 1.86 for Northern Europe, 1.33 for Southern Europe, 1.22 for Central Europe, and 0.65 for Eastern Europe. More cases than expected were registered in all countries with an official VRT registry.Conclusion: The number of cases observed is consistent with expectations, but disparities exist across Europe. Difficulties in diagnosing PPB emerged in most Eastern countries. The incidence rate of PPB may be underestimated. The creation of VRT-dedicated groups and a European Registry for VRTs could help to reduce inequalities.What is Known:• Very rare pediatric tumors are often not recognized, despite representing almost 11% of childhood cancers .• Pleuropulmonary blastoma is a rare pediatric tumor with a poor prognosis.What is New:• The ability to diagnose and register pleuropulmonary blastoma varies in Europe.Registries dedicated to very rare pediatric tumors improve the diagnostic rates.• The incidence rate of pleuropulmonary blastoma may currently be underestimated.

Nephrotic syndrome and Hodgkin lymphoma in children. Report of two cases.

BACKGROUND: The association of nephrotic syndrome (NS) and Hodgkin's lymphoma (HL), although rare, is well recognised. In the majority of cases of HL, minimal change NS is detected. DESCRIPTION OF CASES: This report presents the occurrence of NS in two children with HL. In the first case, NS preceded the diagnosis of lymphoma by 3 months, while in the other child, the two disorders occurred simultaneously. In both cases, clinical manifestations and laboratory parameters (proteinuria) of NS resolved after effective treatment for active HL. CONCLUSION: Prolonged proteinuria may be a paraneoplastic syndrome and HL should be considered in the diagnosis as it is crucial for the management of both entities.

Maternal smoking during pregnancy and childhood lymphoma: a meta-analysis.

Results from epidemiological studies exploring the association between childhood lymphoma and maternal smoking during pregnancy have been contradictory. This meta-analysis included all published cohort (n = 2) and case-control (n = 10) articles; among the latter, the data of the Greek Nationwide Registry for Childhood Hematological Malignancies study were updated to include all recently available cases (-2008). Odds ratios (ORs), relative risks and hazard ratios were appropriately pooled in three separate analyses concerning non-Hodgkin lymphoma (NHL, n = 1,072 cases), Hodgkin lymphoma (HL, n = 538 cases) and any lymphoma (n = 1,591 cases), according to data availability in the included studies. An additional metaregression analysis was conducted to explore dose-response relationships. A statistically significant association between maternal smoking (any vs. no) during pregnancy and risk for childhood NHL was observed (OR = 1.22, 95% confidence interval, CI: 1.03-1.45, fixed effects model), whereas the risk for childhood HL was not statistically significant (OR = 0.90, 95% CI: 0.66-1.21, fixed effects model). The analysis on any lymphoma did not reach statistical significance (OR = 1.10, 95% CI = 0.96-1.27, fixed effects model), possibly because of the case-mix of NHL to HL. No dose-response association was revealed in the metaregression analysis. In conclusion, this meta-analysis points to a modest increase in the risk for childhood NHL, but not HL, among children born by mothers smoking during pregnancy. Further investigation of dose-response phenomena in the NHL association, however, warrants accumulation of additional data.

Delayed exposure to infections and childhood lymphomas: a case-control study.

OBJECTIVES: Delayed exposure to common infections during childhood, have been implied to cause strong immunological response to a single infectious agent that eventually triggers leukemogenesis. The aim of the present study was to investigate whether decreased exposure to infections, as reflected in a more seronegative spectrum to several common infectious agents, is associated with increased risk for the development of childhood lymphomas. METHODS: All 125 children (up to 14 years old), with Hodgkin (HL, n = 52) and non-Hodgkin lymphomas (NHL, n = 73) diagnosed through the national network of childhood Hematology-Oncology units during an 8-year period were enrolled in the study along with 125 age- and gender-matched controls. Past exposure to nine common infections [respiratory syncytial virus (RSV), influenza A and B, parainfluenza type 1, adenovirus, Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes virus 6 (HHV6), Bartonella henselae] was assessed using serological markers. RESULTS: After controlling for possible confounding factors, the overall seronegativity status upon diagnosis was statistically significantly associated with NHL [odds ratio; 95% CI: 1.45 (1.10-1.93), p = 0.01] and less so with HL risk [odds ratio; 95% CI: 1.30 (0.83-2.05), p = 0.25]. A statistically significant association of seronegativity with the development of NHL was evident for RSV [odds ratio; 95% CI: 7.27 (1.59-33.28), p = 0.01], EBV [odds ratio; 95% CI: 6.73 (1.45-31.20), p = 0.01] and suggestive association for influenza B [odds ratio; 95% CI: 2.60 (0.90-7.55), p = 0.08] and influenza A [odds ratio; 95% CI: 2.35 (0.81-6.80), p = 0.11]. In contrast, there was no evidence for association of HL with negative serology for any of the infectious agents tested. CONCLUSIONS: The risk of lymphomas, especially NHL, might be higher when, due to lower exposure to several infectious agents, the relatively unmodulated immune system of a child is challenged by environmental stimuli that can trigger development of lymphomas. The results, however, need further confirmation, through more pertinent methodological designs.

Childhood leukaemias and lymphomas in Greece (1996-2006): a nationwide registration study.

BACKGROUND: Monitoring time trends in the incidence of childhood leukaemias and lymphomas requires efficient and continuous data collecting systems. In countries without official cancer registries, such as Greece, ad hoc nationwide registration of incident childhood leukaemias and lymphomas could help elucidate the underlying aetiology and monitor socioeconomic differentials in health care delivery. METHODS: We registered all cases and produced age, gender, type and immunophenotype specific figures and overall crude and age adjusted annual incidence rates and secular trends for 863 leukaemia and 311 lymphoma incident cases diagnosed in children <15 years of age across Greece during 1996-2006, namely the first 11 years of the Nationwide Registry for Childhood Hematological Malignancies. RESULTS: The epidemiological profiles of leukaemias/lymphomas in Greece are similar to those in industrialised countries. No secular trends are observed for either malignancy during the studied period. However, the calculated incidence for leukaemia (46.60 cases per 1 million children annually) is among the highest in the EU-27 (19% higher than average; p<0.001), whereas that for lymphoma (16.8 cases per 1 million children annually) is around the EU-27 average. CONCLUSIONS: Minimal secular changes in childhood leukaemias/lymphomas have been noted recently in the EU-27, which cannot be easily explained in countries with small populations. Therefore, centralised EU databases such as the Automated Childhood Cancer Information System (ACCIS) should be enlarged to generate sufficient statistical power for monitoring time trends. It would be interesting to explore whether different lifestyle patterns across the EU might be responsible for the observed excess leukaemia incidence in countries such as Greece.

Pleuropulmonary blastoma in the area of a previously diagnosed congenital lung cyst: report of two cases.

Pleuropulmonary blastoma (PPB) is a rare primary malignant pulmonary tumor in pediatric patients. We report the development of PPB in the area of a previous pulmonary cyst in two children, one boy and one girl 5 and 12 years old, respectively. We present the clinical and radiological findings. A short review of the literature is included.

Hickman-Broviac catheter-related infections in children with malignancies.

Infectious complications are frequently encountered following Hickman-Broviac (H-B) catheter insertion. The medical records of 164 children with malignancies who underwent H-B catheter insertion from March 1, 1988 to December 31, 1997 were reviewed retrospectively. During a 35,697 catheter-day period, 77 catheter-related infections occurred, including 50 catheter-insertion-site infections and 27 bloodstream infections. The risk for the development of catheter-related infections was 2.15 per 1000 catheter-days (1.4 and 0.75 per 1000 catheter-days for catheter-insertion-site and bloodstream infections, respectively). In 17 (63%) of 27 episodes of bloodstream infections, antimicrobial treatment controlled the infection without catheter removal. A previous catheter-insertion-site infection caused by Staphylococcus epidermidis (p=0.01), the occurrence of mechanical catheter complications (p=0.007), and a normal coagulation status of the host (p=0.03) were significantly associated with the development of catheter-related bloodstream infections. H-B catheters remain important in pediatric oncology. Due to the significant morbidity associated with the development of catheter-related bloodstream infections, risk factors found to increase the incidence rate of such infections must be identified and properly managed.

Electrical power lines and childhood leukemia: a study from Greece.

Residential proximity to electrical power lines of different voltage in relation to childhood leukemia was investigated through a case-control study undertaken in Greece during 1993-1994. The study comprised 117 incident cases of childhood leukemia and 202 age-, gender- and place-of-residence-matched controls. Four measures of exposure to magnetic fields were developed, using data provided by the Public Power Corporation of Greece: Voltage (V) divided by the distance (d), V/d2, V/d3 and an adaptation of the Wertheimer-Leeper code. Conditional-logistic-regression modeling was used to adjust for potential confounding influences of 18 variables. No significant trends of childhood leukemia risk with increasing exposure levels were noted, nor were there statistically significant elevations of disease risk at the higher exposure levels in each measure of exposure. These results do not support a causal link between residential proximity to electrical high-voltage wires and childhood leukemia risk, but in themselves do not refute a weak empirical association.

The risk profile of childhood leukaemia in Greece: a nationwide case-control study.

The risk profile of childhood leukaemia in Greece was studied through a case-control investigation that included all 153 incident cases of the disease, ascertained throughout the country during 1993 and 1994, and two hospital controls for every case matched for gender, age and place of residence. The data were analysed using conditional logistic regression and the associations are expressed in terms of adjusted odds ratios (OR) and their 95% confidence intervals. Cases were born to mothers of a higher standard education, the OR for an increment of four schooling years being 1.48 (1.17-1.87) and had higher birth weight, the OR for an increment of 500g being 1.36 (1.04-1.77). Pet ownership and birth after a pregnancy with anaemia were associated with increased risk, the ORs being 2.18 (1.14-4.16) and 2.60 (1.39-4.86) respectively. From the frequency analyses, indicative inverse associations were found with birth order, household crowding and previous hospitalization with allergic diseases, whereas indicative positive associations were found with diabetes mellitus during pregnancy and with neonatal jaundice. Substantial or significant elevations were not found with respect to maternal smoking and coffee drinking during pregnancy, diagnostic radiography and ultrasonographic examinations or blood transfusions. A significant inverse association with maternal consumption of alcohol could be due to multiple comparisons, but a detrimental effect can probably be excluded. A non-significant positive association with total shots of viral vaccinations and a weak non-significant inverse association with breast feeding were also found. We interpret the findings of this study as being compatible with acute childhood leukaemia being linked with delayed development of herd immunity to fairly common infectious agents, in conjunction with accelerated perinatal and early post-natal growth.