Breastfeeding and risk of childhood brain tumors: a report from the Childhood Cancer and Leukemia International Consortium

PURPOSE

Studies report mixed findings regarding the association of breastfeeding with childhood brain tumors (CBT), the leading causes of cancer-related mortality in young people. Our objective was to determine whether breastfeeding is associated with CBT incidence.

METHODS

We pooled data on N = 2610 cases with CBT (including 697 cases with astrocytoma, 447 cases with medulloblastoma/primitive neuroectodermal tumor [PNET], 167 cases with ependymoma) and N = 8128 age- and sex-matched controls in the Childhood Cancer and Leukemia International Consortium. We computed unconditional logistic regression models to estimate the odds ratio (OR) and 95% confidence interval (CI) of CBT, astrocytoma, medulloblastoma/PNET, and ependymoma according to breastfeeding status, adjusting for study, sex, mode of delivery, birthweight, age at diagnosis/interview, maternal age at delivery, maternal educational attainment, and maternal race/ethnicity. We evaluated any breastfeeding versus none and breastfeeding ≥ 6 months versus none. We subsequently performed random effects meta-analysis to confirm our findings, identify potential sources of heterogeneity, and evaluate for outliers or influential studies.

RESULTS

Breastfeeding was reported by 64.8% of control mothers and 64.5% of case mothers and was not associated with CBT (OR 1.04, 95% CI 0.94-1.15), astrocytoma (OR 1.01, 95% CI 0.87-1.17), medulloblastoma/PNET (OR 1.11, 95% CI 0.93-1.32), or ependymoma (OR 1.06, 95% CI 0.81-1.40). Results were similar when we restricted to breastfeeding ≥ 6 months and in meta-analyses.

CONCLUSION

Our data suggest that breastfeeding does not protect against CBT.

Medulloblastoma and primitive neuroectodermal tumors

Medulloblastomas and sPNETs remain highly problematic tumors to treat. Prognosis has improved over the past two decades, but many children who survive treatment have significant long-term sequelae. The improvements in outcome have been due to advances in surgical techniques, the wider use of chemotherapy, and the more judicious use of radiotherapy. For further improvements,the recent impressive discoveries concerning molecular mechanisms of embryonal tumor origin, development,and growth will need to be translated into molecularly based, risk-adapted therapy.

Supratentorial primitive neuroectodermal tumors: a Canadian pediatric brain tumor consortium report

INTRODUCTION

Supratentorial primitive neuroectodermal tumors (SPNET) are rare tumors accounting for only 2.5% of childhood brain tumors. The purpose of this study was to describe the range of treatment regimens used to treat pediatric SPNET in Canada and to identify prognostic factors for overall survival in this population.

METHODS

This study was a retrospective clinical analysis of SPNET patients treated over the last 10 years in Canada. A questionnaire was developed and distributed to all institutions in Canada who treat pediatric patients. Data were collected for patients <19 years of age who were diagnosed and treated for SPNET between 1995 and 2005.

RESULTS

Data were obtained for 48 eligible patients. The stages of patients for whom complete data were provided were 80, 3, and 16% for metastatic stage M0, M1, and M2/3, respectively. The best responses to therapy included complete response in 44%, partial response in 8%, still on therapy in 2%, progressive disease in 31%, toxic death in 2%, and no therapy given in 12%. The 4-year survival was 37.7 +/- 7.6%. The factors associated with an increase in survival were the use of radiation therapy and chemotherapy, and age >2 years. Overall survival was not affected by metastatic disease at diagnosis, tumor site, or degree of initial resection.

CONCLUSIONS

Survival is poor in SPNET patients but highest in those who received chemotherapy and radiation therapy. Further studies are needed to improve the survival of these patients.

Incidence and severity of postoperative cerebellar mutism syndrome in children with medulloblastoma: a prospective study by the Children's Oncology Group

OBJECT

Cerebellar mutism syndrome (CMS) is a unique postoperative syndrome typically arising 1 to 2 days after resection of a midline posterior fossa tumor; it consists of diminished speech progressing to mutism, emotional lability, hypotonia, and ataxia. Most descriptions have been limited to small institutional series using a retrospective chart review methodology.

METHODS

The authors incorporated a CMS questionnaire in two large clinical trials (Children's Cancer Group [CCG] 9931, treatment for high-risk medulloblastoma/primitive neuroectodermal tumor; and CCG/Pediatric Oncology Group [POG] A9961, treatment for average-risk medulloblastoma) to prospectively survey for incidence, severity, and possible causes of CMS in children with newly diagnosed medulloblastoma. Information pertaining to 450 of the 463 patients enrolled in the studies was available for review (82 patients in CCG 9931, and 368 patients in CCG/POG A9961). Cerebellar mutism syndrome occurred in 107 (24%) of 450 children. Symptom intensity was judged to have been severe in 43%, moderate in 49%, and mild in 8% of these 107 patients. Mutism and ataxia were the features most frequently judged as severe. In both cohorts, preoperative brainstem invasion was the only feature that correlated with risk of CMS. One year after diagnosis, nonmotor speech/language deficits, neurocognitive deficits, and/or ataxia persisted in a significant fraction of patients.

CONCLUSIONS

Nearly one quarter of patients who underwent resection of a medulloblastoma developed symptoms of CMS, of which 92% were judged to be of moderate or severe intensity. Brainstem invasion by tumor was the only risk factor that correlated positively with CMS occurrence; there was a negative correlation with cerebellar hemisphere tumor location. As more radical resections are attempted for medulloblastoma, the potential for increased morbidity must be carefully weighed against prognostic factors, especially in patients with brainstem invasion.

Parental heat exposure and risk of childhood brain tumor: a Children's Oncology Group study

Medulloblastoma (MB) and primitive neuroectodermal tumor (PNET) are histologically similar brain tumors that occur mostly in children. As part of a comprehensive case-control study of MB/PNET, this study explored parental exposure to heat and electromagnetic fields as potential risk factors. Parents of 318 cases (<6 years of age at diagnosis in 1991-1997 and registered with the Children's Cancer Group) and 318 controls selected by random digit dialing were interviewed. In univariate analyses, moderately strong associations were observed for mother's sauna use close to conception (odds ratio = 3.8, 95% confidence interval (CI): 1.0, 13.7) or in the first trimester (odds ratio = 3.6, 95% CI: 0.7, 17.3) and for father's exposure in the 3 months before the pregnancy to sauna (odds ratio = 2.4, 95% CI: 1.3, 4.5), electric blanket (odds ratio = 2.0, 95% CI: 0.9, 4.3), or any heat source (for higher exposure: odds ratio = 2.5, 95% CI: 1.4, 4.6). In multivariate models, father's sauna use and father's exposure to any heat source were associated with MB/PNET in a dose-response fashion (for high exposure: odds ratio = 3.4, 95% CI: 1.2, 9.7, and odds ratio = 2.1, 95% CI: 1.1, 4.3, respectively). This new observation regarding paternal exposure to heat just prior to the index pregnancy deserves consideration in future animal and human studies of MB/PNET.

Risk of brain tumors in children and susceptibility to organophosphorus insecticides: the potential role of paraoxonase (PON1)

Prior research suggests that childhood brain tumors (CBTs) may be associated with exposure to pesticides. Organophosphorus insecticides (OPs) target the developing nervous system, and until recently, the most common residential insecticides were chlorpyrifos and diazinon, two OPs metabolized in the body through the cytochrome P450/paraoxonase 1 (PON1) pathway. To investigate whether two common PON1 polymorphisms, C-108T and Q192R, are associated with CBT occurrence, we conducted a population-based study of 66 cases and 236 controls using DNA from neonatal screening archive specimens in Washington State, linked to interview data. The risk of CBT was nonsignificantly increased in relation to the inefficient PON1 promoter allele [per PON1(-108T) allele, relative to PON1(-108CC): odds ratio (OR) = 1.4; 95% confidence interval (CI), 1.0-2.2; p-value for trend = 0.07]. Notably, this association was strongest and statistically significant among children whose mothers reported chemical treatment of the home for pests during pregnancy or childhood (per PON1(-108T) allele: among exposed, OR = 2.6; 95% CI, 1.2-5.5; among unexposed, OR = 0.9; 95% CI, 0.5-1.6) and for primitive neuroectodermal tumors (per PON1(-108T) allele: OR = 2.4; 95% CI, 1.1-5.4). The Q192R polymorphism, which alters the structure of PON1 and influences enzyme activity in a substrate-dependent manner, was not associated with CBT risk, nor was the PON1(C-108T/Q192R) haplotype. These results are consistent with an inverse association between PON1 levels and CBT occurrence, perhaps because of PON1's ability to detoxify OPs common in children's environments. Larger studies that measure plasma PON1 levels and incorporate more accurate estimates of pesticide exposure will be required to confirm these observations.

Primitive neuroectodermal tumor of the head and neck: incidence, diagnosis, and management

Primitive neuroectodermal tumors are in the Ewing's sarcoma family of tumors and are composed of small round cells. Because of their rare occurrence, optimal therapy is challenging, particularly if they occur in the head and neck. Diagnosis is based on history, immunostaining with at least 2 neural markers, ultrastructural examination, and evidence of an abnormal t(11;22)(q24;q12) translocation as the hallmark for the Ewing's sarcoma family. The prognosis in general is poor because of overt metastasis at the time of diagnosis. Of 27 reported patients with primitive neuroectodermal tumors of the head and neck, 23 were less than 20 years of age. Most patients presented with a tumor in the nasal cavity, paranasal sinuses, or neck. Symptoms developed rapidly (3.6 months, on average), and a lethal outcome occurred in 9 patients. This highly malignant tumor requires an aggressive combination of radical resection, chemotherapy, and radiotherapy. A close follow-up with regular radiographic examination for at least 5 years is mandatory.

A national case-control study of Ewing's sarcoma family of tumours in Australia

Limited population-based epidemiologic information is available on Ewing's sarcoma family of tumours (ESFT), a rare group of neoplasms. Several associations have been noted on a few studies but results were not consistent, except for exposure to farming among cases and their parents. Here we present the non-farm findings of a nationwide case-control study of ESFT in children and young adults in Australia. The analysis included 106 persons with confirmed ESFT and 344 population-based controls selected randomly via telephone. Information was collected by interview (84% face to face). We found a strong and significant association of ESFT with hernias, in particular hernia repaired in hospital (OR = 5.6, 95% CI 1.3-6.4). Among other factors, there was a near doubling of risk for males, and male cases had their pubertal signs earlier (started shaving earlier) than male controls. There was also an increased risk of ESFT at higher levels of self-assessed exercise, but no other factor really stood out. For pregnancy-related factors, there was a tripling of risk for glandular fever, a doubling of risk for urinary tract infection and a near doubling of risk for X-rays during or just before pregnancy, but these estimates were not significant. In addition, there was a large number of inverse associations with medical conditions (specifically bone disorders), case exposure to medications, vaccinations and X-rays, with ultrasound during the pregnancy having the most certain effects. We conclude that, although the aetiology of ESFT remains obscure, overall there is strong evidence of an association with inguinal hernia; this can now be added to the farm-associated risk reported by others and us. The other associations reported here await replication and refinement in future studies.

Oligogenic segregation analysis of hereditary prostate cancer pedigrees: evidence for multiple loci affecting age at onset

Previous studies have suggested strong evidence for a hereditary component to prostate cancer (PC) susceptibility. Here, we analyze 3,796 individuals in 263 PC families recruited as part of the ongoing Prostate Cancer Genetic Research Study (PROGRESS). We use Markov chain Monte Carlo (MCMC) oligogenic segregation analysis to estimate the number of quantitative trait loci (QTLs) and their contribution to the variance in age at onset of hereditary PC (HPC). We estimate 2 covariate effects: diagnosis of PC before and after prostate-specific antigen (PSA) test availability, and presence/absence of at least 1 blood relative with primary neuroepithelial brain cancer (BC). We find evidence that 2 to 3 QTLs contribute to the variance in age at onset of HPC. The 2 QTLs with the largest contribution to the total variance are both effectively dominant loci. We find that the covariate for diagnosis before and after PSA test availability is important. Our findings for the number of QTLs contributing to HPC and the variance contribution of these QTLs will be instructive in mapping and identifying these genes.

Incidence and trends in pediatric malignancies medulloblastoma/primitive neuroectodermal tumor: a SEER update. Surveillance Epidemiology and End Results

BACKGROUND

It has been suggested that cerebellar medulloblastoma (M) and primitive neuroectodermal tumors (PNET) arising elsewhere in the nervous system, represent a single entity (M/PNET), although this concept is controversial. Cancer registries permit population-based description of cases reported as medulloblastoma, those reported as PNET and description of the aggregate, M/PNET.

PROCEDURE

We reviewed the 768 cases of M/PNET (633 diagnosed medulloblastoma and 135 diagnosed PNET) among persons under 20 years of age in the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) database.

RESULTS

The incidence of M/PNET rose 23%, from 4 per 10(6) person-years in 1973-77 to 4.9 per 10(6) person-years in 1993-98. Cases reported as PNET were more likely than those reported as medulloblastoma to be supratentorial (30.4% vs. 1.9%, P < 0.001) and to be female (42.2% vs. 35.4%, P = 0.13). The difference in 5-year survival between the 600 children with infratentorial medulloblastoma vs. the 49 children with infratentorial PNET was not statistically significant (55% vs. 43%). Regardless of reporting diagnosis, survival was poorer among children age 0-3 years and those with supratentorial tumors. Children diagnosed in the more recent period from 1985-1998 had a longer median survival than children diagnosed in 1973-84 (4.9 years vs. 10 years, P < 0.05). Rates were 42% higher among Whites compared to Blacks (4.5/10(6) person-years vs. 3.1/10(6) person-years, P < 0.01).

CONCLUSIONS

We found M/PNET is increasing in incidence and more frequent among Whites. Given that medulloblastoma and PNET are histologically identical and have similar epidemiologic profiles, future studies should provide analyses that combine these entities.

Parental occupations and childhood brain tumors: results of an international case-control study

OBJECTIVE

To evaluate the role of parental occupations in the etiology of childhood brain tumors (CBT).

METHODS

Population-based case-control studies were conducted concurrently in seven countries under the coordination of the International Agency for Research on Cancer, gathering 1,218 cases and 2,223 controls. We report here the findings related to parental occupations during the 5-year period before the child's birth. Risk estimates related to a number of paternal and maternal occupations were obtained by unconditional logistic regression adjusted for age, sex, year of birth, and center, for all types of CBT combined and for the subgroups of astroglial, primitive neuroectodermal tumors (PNET), and other glial tumors.

RESULTS

An increased risk in relation with agricultural work was seen for all CBT combined and for other glial tumors. Increased risks for all tumors and PNET were seen for paternal occupation as an electrician; the same pattern held for maternal occupation when children under 5 were selected. Paternal occupation as a driver or mechanic, and maternal work in an environment related to motor-vehicles were associated with an increased risk for all CBT and astroglial tumors. More case mothers compared to control mothers were employed in the textile industry.

CONCLUSION

Our study reinforces previous findings relative to the role of parental work in agriculture, electricity, or motor-vehicle related occupations and maternal work in the textile industry. It does not confirm previous associations with work environments including aerospace, the chemical industry, or the food industry, or with maternal occupation as a hairdresser, a nurse, or a sewing machinist, and paternal occupation as a welder.

Absence of germline and somatic p53 alterations in children with sporadic brain tumors

Cancers of the central nervous system are the most common solid tumors of childhood. Although somatic alterations of the p53 tumor suppressor gene have been implicated in brain tumorigenesis, the role of germline p53 mutations in the development of childhood brain tumors has not been well defined. As a component of an ongoing extensive study of the epidemiology of childhood brain tumors, we prospectively examined the germline and tumor p53 gene status in 85 children without a family history of cancer who were diagnosed with a sporadic malignant central nervous system tumor. Using PCR/single-strand conformational polymorphism analysis and direct DNA sequencing, 85 children were screened for the presence of constitutional p53 sequence alterations in exons 2 and 4 through 11. No mutations were identified. Commonly reported sequence polymorphisms were observed at codon 72, as well as in 2 other previously described nucleotide residues. Forty-four brain tumor samples were available for analysis and of these 40 were paired with peripheral blood. Once again, no p53 mutations were found. Of the 5 germline samples with the 2 common polymorphisms, only one had a paired tumor sample for comparison and the tumor contained the same alteration as the germline. Of note, one tumor, a PNET of the cerebellum (medulloblastoma), showed loss of heterozygosity at codon 72. We can conclude that the frequency of germline and somatic p53 mutations in sporadic childhood brain tumors is very low, probably less than 1%, and there is no need to screen these patients routinely for their germline p53 status. However, the potential significance of LOH at codon 72 remains to be elucidated.

[Epidemiology of childhood brain tumors]

The German Childhood Cancer Registry (GCCR) was established in 1980. From 1980 to 1997 4,447 CNS tumours in children below 15 years of age have been reported to the registry. From 1988 to 1997 the average annual incidence was 2.5/100,000 children. This corresponds to 19.2% of the registered diseases. Compared with incidence rates reported from other developed countries one can estimate that there is about 25% underreporting of CNS tumours in the GCCR. This is in contrast to the relatively complete ascertainment of other childhood malignancies (above 95%). Based on 3012 incident cases from 1988 to 1997 the Kaplan-Meier-estimate of 5-year-survival probability is 65% for all CNS tumours and 54% for PNETs and gliomas. An active long-term-follow-up shows that 30% of 142 children with secondary neoplasms following primary lymphoid leukaemias developed a CNS tumour. Following any primary childhood malignancies 45 CNS tumours were recorded, amongst these were one third leukaemias. The paper reports first results from a population based case control study which included 466 children with CNS tumours and 2,458 healthy controls. These indicate an increased risk for children with low birth weight and for children whose mothers smoked during pregnancy. Additional data can be found in the Internet (http:¿info.imsd.uni-mainz.de/K_Krebsregister).

Medulloblastoma: clinical and biologic aspects

Medulloblastoma is the most common childhood primary CNS tumor, and treatment approaches have evolved over the past three decades. The biologic underpinnings of medulloblastoma are not fully characterized, but recent work has identified new, important directions for research. Stratification of patients with medulloblastoma into risk groups is the backbone of most ongoing therapeutic studies. Patients are usually characterized as being either average risk or poor risk, although an intermediate risk group may exist. Standard treatment for older children with medulloblastoma consists of radiation and, for most, chemotherapy. Children with nondisseminated disease at the time of diagnosis have been reported to have as high as an 80% five-year disease-free survival rate after treatment with reduced dose (2340 cGy) craniospinal irradiation, local boost radiation therapy (5500 cGy), and chemotherapy, given during and after radiation therapy. Preradiation chemotherapy has yet to be shown to be of benefit for children with medulloblastoma. Children with disseminated disease are a highly problematic subgroup of patients to treat. A variety of new approaches are being studied, most of which are intensifying chemotherapy either prior to or after radiation. Long-term survivors of medulloblastoma are at significant risk for permanent endocrinologic, cognitive, and psychological sequelae. Infants and very young children with medulloblastoma remain a difficult therapeutic challenge because they have the most virulent form of the disease and are at highest risk for treatment-related sequelae.

Immunohistochemical evaluation of small round cell tumors of childhood

OBJECTIVE

This study was done to evaluate the pediatric undifferentiated small round cell tumors with immunohistochemical staining.

SETTING

The present study included consecutive cases of small round cell tumors which were diagnosed in children (< 15 years) in the section of Histopathology at the Aga Khan University Hospital, Karachi during the period of two years.

METHODS

The group of undifferentiated small round cell tumors were evaluated immunohistochemically by using a panel of antibodies on sections from routinely processed, formalin fixed, paraffin embedded tissue blocks.

RESULTS

The category of undifferentiated small round cell tumors included rhabdomyosarcoma (23.2%), primitive neuroectodermal tumor (17.9%), non-Hodgkin's lymphoma (16.1%), neuroblastoma (14.2%), Ewing's sarcoma (10.7%) in order of frequency. Osteosarcoma (Small cell variant), retinoblastoma and medulloblastoma comprised 1.8% each. In seven cases (12.5%), the immunohistochemical analysis was inconclusive.

CONCLUSION

Immunohistochemistry is a very valuable diagnostic tool which helps in distinguishing the undifferentiated tumors especially small round cell tumors. The immunohistochemical staining needs to be performed routinely for undifferentiated tumors in diagnostic histopathology.

Incidence and survival of childhood CNS tumours in the Region of Lombardy, Italy

Incidence rates for CNS tumours in children of age 0-14 years in the Region of Lombardy, Italy, during the period 1988-93 were analysed; survival probability updated to December 1995 was also estimated. CNS tumours defined according to the International Classification of Diseases for Oncology codes were actively searched for. CNS tumours were diagnosed in 296 children. The age-standardized rates were 40.0 per million child years for both sexes together, and 45.3 for boys and 34.4 for girls. In all age groups, boys had a higher incidence than girls. The annual incidences were 13.7, 7.0, 5.8 for astrocytoma, medulloblastoma and ependymoma, respectively. The overall survival percentages at 5 and 8 years after diagnosis were 68 and 66, respectively. Prognosis was good for astrocytoma (5-year survival, 81%), and declined in the order: other gliomas (5-year survival, 76%); ependymoma (5-year survival, 62%), and medulloblastoma (5-year survival, 43%). The histological type of the tumour was the most powerful independent predictor of survival in children with a CNS tumour. Medulloblastoma/primitive neuroectodermal tumours appeared to have the highest risk of a poor prognosis compared with astrocytoma (relative risk, 3.27; 95% confidence interval, 1.81-5.91). Age at diagnosis and sex had no significant effect on survival. The incidence of childhood CNS tumours found in this study is higher than previously reported in Italy, and is one of the highest in the world from population-based data. Survival of children with brain tumours has improved greatly in recent years. These results suggest that children in Lombardy with CNS tumours had a good survival experience compatible with high quality of care.

Parental occupation and childhood brain tumors: astroglial and primitive neuroectodermal tumors

Data from a population-based case-control study in 19 counties in California and Washington State were used to investigate the association between parental employment and childhood brain tumors. Parents of 540 cases (including 308 astroglial and 109 primitive neuroectodermal tumors) and 801 controls diagnosed from 1984 to 1991 were interviewed. Analysis was completed for parents' self-reported industry of employment and job tasks during the five years preceding the birth of the child. Parents who worked in the chemical industry were at increased risk of having had children with astroglial tumors (fathers' odds ratio [OR] = 2.1; 95% confidence interval [CI], 1.1-3.9); mothers' OR = 3.3; 95% CI, 1.4-7.7), but no trend by duration of employment was seen for mothers. Children of fathers employed as electrical workers were at increased risk of developing brain tumors of any histologic type (OR = 2.3; 95% CI, 1.3-4.0).

Primitive peripheral neuroectodermal tumors Mayagüez Medical Center experience

Primitive neuroectodermal or neuroepithelial tumors are names used to describe neoplasias composed of undifferentiated cells resembling germinal cells of the embryonic neural tube. These tumors are small round cell malignancies of the neural crest origin arising outside the central and sympathetic nervous system. They are described as peripheral and central neuroectodermal tumors related to the original malignant cell. A great number of tumors are described under this classification in spite of the fact that there is no an universal acceptance that these small-cell neoplasms, regardless of their primary site, are derived from immature neuroectoderm tissue. Because one tumor resembles others in terms of its phenotypic expression, multiple specific studies such as clinical profile, ultrastructural, immunocytochemical, and cytogenetic features should be studied, since no single clinical or laboratory marker is by itself diagnostic. However, there is a chromosomal reciprocal translocation, t(11;22)(q24;q12), which is unique to Primitive Neuroectodermal Tumor (PNET).

Primary intracranial neoplasms of infancy and early childhood

We investigated the age-related location, gender distribution, and histology of 107 brain tumors in children under 4 years of age seen in our department between 1984 and 1997. The male-to-female ratio was 1.4 (62/45 cases) with a prevalence of supratentorial tumors (60/47 = 1.3); the main histological entity was astrocytoma (33.6%), followed by ependymoma (14.0%). In the 1st year of life 22 cerebral neoplasms became clinically apparent. A higher ratio for supratentorial tumors was revealed (17/5 = 3.4), but without gender preference, and primitive neuroectodermal tumors (PNET) were the most frequent (5/22). In the 2nd year 25 tumors were found. The male-to-female ratio was 1.5 (15/10) and the supratentorial-to-infratentorial ratio, 1.1 (13/12). The two most common entities were astrocytoma and ependymoma (6 cases each). In addition, a survey of previously published investigations into this subject was performed and a compilation of data on 1960, 545 and 1084 tumors in children below the age of 1, 2 and 4 years, respectively, was prepared, which makes it the most extensive review of brain tumors of infancy and early childhood yet undertaken.

p53 gene mutation in cerebral primitive neuroectodermal tumor in Taiwan

p53 mutation has been rarely reported in cerebral primitive neuroectodermal tumors (PNET). To determine the significance of p53 mutations in the development of cerebral PNET, we studied cerebral PNET samples from 14 patients, 8 females and 6 males with a mean age of 38 years (range 10 months to 77 years) who had total or subtotal surgical resection. Histological typing of PNET with neuronal (N) and non-neuronal (NN) differentiation groups revealed 8 and 6 cases, respectively. Six (43%) of the 14 patients had p53 mutation. The p53(+) and p53(-) groups had an age range of 19-77 with a mean of 49 years and 10 months to 57 years with a mean of 30 years, respectively. p53 expression between the PNET-N and PNET-NN groups was 5 of 8 (62.5%) and 1 of 6 (16.7%), respectively. The mutations contained 3 transitions, 2 transversions and 1 frameshift; none of them occurred at the site of 'hot-spot' residues (codons 175, 248, 273). The results suggest that: (1) p53 mutation in cerebral PNET tends to show a higher incidence of neuronal differentiation and occurs in the older age group in Taiwan, (2) there was no difference in survival time between the PNET-N and PNET-NN groups (7 months and 6 months) (P = 0.54), and between p53(+) and p53(-) groups (6 months and 7 months) (P = 0.57), and (3) PNET may be an entity of a heterogenous group of tumors with different genetic mechanisms controlling their trends of differential lineage. Further studies are needed to determine the significance of p53 mutations in PNET development, especially the role of carcinogens in the genesis of PNET in Taiwan.

Malignant laryngeal tumors in children: a 15-year experience with four patients

Malignant laryngeal neoplasms in children are uncommon and present diagnostic and therapeutic challenges. A 15-year retrospective review of laryngeal tumors at our institution identified four patients with malignant neoplasms. These children, 7 months to 16 years of age, were treated for squamous cell carcinoma, choriocarcinoma, rhabdomyosarcoma, and primitive neuroectodermal tumor. This report details these cases, emphasizing diagnostic approaches, treatment decisions (medical oncologic management, surgical resection), and rehabilitation measures for postlaryngectomy communication. A multi-institutional pediatric head and neck tumor registry would be a useful reference to assist with individual treatment decisions.

Risk factors for astrocytic glioma and primitive neuroectodermal tumor of the brain in young children: a report from the Children's Cancer Group

We conducted a matched case-control study to investigate risk factors for the two most common types of brain tumors in children, astrocytic glioma and primitive neuroectodermal tumor (PNET). Since the study focused on gestational exposures, we restricted it to young children because these exposures would be expected to act early in life. Parents of 155 astrocytic glioma cases, 166 PNET cases, and controls identified by random digit dialing completed telephone interviews. Few associations occurred with the hypothesized risk factors, which were gestational exposure to alcohol, hair coloring products, farms, and substances containing N-nitroso compounds (passive smoking, makeup, incense, new cars, pacifiers, baby bottles, beer). Of the products studied that contain N-nitroso compounds, only beer was associated with a significantly increased risk of either tumor type [odds ratio (OR) for PNET = 4.0; 95% confidence interval (CI), 1.1-22.1; P = 0.04]. Elevated ORs for PNET were observed for farm residence of the mother during the pregnancy (OR = 3.7; 95% CI, 0.8-23.9; P = 0.06) and of the child for at least a year (OR = 5.0; 95% CI, 1.1-46.8; P = 0.04). Significant associations with astrocytoma were observed for mother's use of kerosene (OR = 8.9; 95% CI, 1.1-71.1; P = 0.04) and birth by Caesarean section (OR = 1.8; 95% CI, 1.1-3.2; P = 0.03). History of miscarriage was associated with a lower risk of PNET (OR = 0.5; 95% CI, 0.3-0.9; P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Maternal diet and risk of astrocytic glioma in children: a report from the Childrens Cancer Group (United States and Canada)

N-nitroso compounds and their precursors, nitrites and nitrates, have been hypothesized as risk factors, and vitamins C and E, which inhibit N-nitroso formation, as protective factors for brain tumors. A case-control study of maternal diet during pregnancy and risk of astrocytoma, the most common childhood brain tumor, was conducted by the Childrens Cancer Group. The study included 155 cases under age six at diagnosis and the same number of matched controls selected by random-digit dialing. A trend was observed for consumption of cured meats, which contain preformed nitrosamines (a class of N-nitroso compounds) and their precursors (adjusted odds ratio [OR] for highest quartile of intake relative to lowest = 1.7, P trend = 0.10). However, no strong trends were observed for nitrosamine (OR = 0.8, P = 0.60); nitrite (OR = 1.3, P = 0.54); nitrate (OR = 0.7, P = 0.43); vitamin C (OR = 0.7, P = 0.37); or vitamin E (OR = 0.7, P = 0.48). Iron supplements were associated with a significant decrease in risk (OR = 0.5, 95 percent confidence interval = 0.3-0.8). The effect of several dietary factors differed by income level, making interpretation of the results difficult. Future research should investigate the effect of dietary components not assessed in this study, as these may explain the disparate effects by income level. The results of this study provide limited support for the nitrosamine hypothesis.

Family history of cancer and seizures in young children with brain tumors: a report from the Childrens Cancer Group (United States and Canada)

The occurrence of cancer and neurological disorders in first- and second-degree relatives of children in the United States and Canada diagnosed with brain tumor before age six was investigated. A pair-matched case-control study with 155 astrocytoma and 166 primitive neuroectodermal tumor (PNET) cases was performed. Cases were identified through the Childrens Cancer Group. Controls were selected by random-digit dialing and matched to cases on age, race, and telephone area code and exchange. Childhood cancers were more common in PNET relatives compared with the general population (standardized incidence ratio [SIR] = 2.5, 95 percent confidence interval [CI] 1.1-4.8, P = 0.02) and with control relatives (odds ratio [OR] = 3.0, CI = 0.5-30, P = 0.29). For astrocytoma, nonsignificant excesses of brain tumor, leukemia/lymphoma, and childhood cancer occurred among case relatives compared with control relatives, but not compared with the general population. Astrocytoma cases were significantly more likely than controls to have a relative with seizures (OR = 2.5, CI = 1.2-4.9, P = 0.009), especially childhood seizures (OR = 3.4, CI = 1.2-12, P = 0.02), epilepsy (OR = 3.0, CI = 0.9-13, P = 0.08), and febrile convulsions (OR = 4.5, CI = 0.9-43, P = 0.07). A family history of stroke was not a risk factor for either type of brain tumor. These results suggest that some childhood brain tumors may result from a genetic susceptibility and that some risk factors may affect childhood astrocytoma and PNET differently.