CHILDHOOD BRAIN TUMORS AND N-NITROSO EXPOSURES

儿童脑肿瘤（CBT）是最常见的实体瘤， 0-19岁儿童。 迄今为止进行的CBT流行病学研究 这表明，长期怀疑的BT风险因素，如电离 辐射、头部创伤和已知的遗传倾向 只有一小部分事故案例。 一个令人信服 实验模型表明，N-亚硝基化合物（NOC） 可能会导致人类的BT，特别是当暴露 经胎盘的 因为肿瘤是由 非人灵长类动物的经胎盘NOC暴露发生在 年轻的成年人以及未成年的动物，这似乎是合理的， 我们的CBT研究包括所有诊断到20岁的病例。 这 美国的研究，与同期的 国际研究，将是第一个专注于NOC/CBT 假说. 我们建议研究1984年以来诊断的所有原发性BT病例- 1990年生活在西部所有地区的0-19岁儿童 基于人口的肿瘤登记所覆盖的海岸;这 包括洛杉矶（LA）、弗朗西斯科（SF）、 和西雅图地区。 在旧金山和西雅图，我们希望采访 105名儿童的生物学母亲被诊断患有BT， 在洛杉矶，我们预计将采访300个病例 妈妈们 在每个区域中，随机数字拨号控制按 年龄和性别将按照对照组：病例组2：1的比例选择 西雅图和洛杉矶1：1。 我们希望完成对 510例CBT病例和720例对照的母亲以及1000名父亲。 调查问卷询问NOC暴露的来源，例如 饮食、饮用水、药品、化妆品、橡胶制品和 父母职业暴露。 所有病例的病理切片将由一名儿科医生审查。 神经病理学家 三个西海岸地区的数据将 单独分析，也将合并。 将合并的 西海岸研究将有足够的统计能力进行 对两种最常见的CBT组织学类型进行单独分析， 星形细胞瘤和髓母细胞瘤。 数据也将具有可比性 来自一项同期国际研究的数据。 的数据 拟议的西海岸研究将与来自 进行国际研究，以便能够对几个 不太常见的组织学类型。

Childhood brain tumors (CBT) are the most common solid tumor in children ages 0-19. Epidemiologic studies of CBT done to date suggest that long suspected BT risk factors such as ionizing radiation, head trauma and known genetic predispositions account for only a small proportion of incident cases. A compelling experimental model suggests that N-nitroso compounds (NOC) may cause BT in humans, particularly when exposure is transplacental. Since the tumors that are induced by transplacental NOC exposure of non-human primates occur in young adult as well as in immature animals it seems reasonable in our CBT study to include all cases diagnosed to age 20. This proposed U.S. study, in conjunction with the concurrent international study, will be the first to focus on the NOC/CBT hypothesis. We propose to study all cases of primary BT diagnosed from 1984- 1990 among children ages 0-19 living in all areas of the West Coast that are covered by population-based tumor registries; this includes 19 counties in the Los Angeles (LA), San Francisco (SF) and Seattle areas. In both SF and Seattle we expect to interview the biological mothers of 105 children with BT diagnosed during this 7 year period; in LA we expect to interview 300 case mothers. In each region random digit dial controls stratified by age and sex will be selected with a control:case ratio of 2:1 for SF and Seattle and 1:1 in LA. We expect to complete interviews with mothers of 510 CBT cases and 720 controls and with 1000 fathers. The questionnaire asks about sources of NOC exposure such as diet, drinking water, drugs, cosmetics, rubber products and parental occupational exposures. Pathology slides of all cases will be reviewed by a single pediatric neuropathologist. Data for each of the 3 West Coast regions will be analyzed separately and will also be pooled. The combined West Coast study will have sufficient statistical power to conduct separate analyses for the 2 most common histologic types of CBT- astrocytoma and medulloblastoma. Data will also be comparable with data from a concurrent international study. Data from the proposed West Coast study will be combined with data from the international study to enable separate analyses for several of the less common histologic types.