Nutrition and Thyroid Cancer Risk in the CTS Cohort

描述（由申请人提供）： 在过去10年中，妇女甲状腺癌发病率的增长速度超过了妇女或男子的任何其他癌症。然而，其原因在很大程度上仍然是未知的，尽管已经出现了几个与营养有关的有希望的途径。拟议的研究将使用以前收集的前瞻性数据来验证和扩展这些发现。此外，我们将讨论一个新出现的关于胰岛素对甲状腺癌风险影响的假设。我们的具体目标是：（1）评估乳头状甲状腺癌风险与（a）十字花科蔬菜和异硫氰酸酯之间的关系，使用新开发的数据库，以及（B）总体和腹部肥胖;以及（2）评估乳头状甲状腺癌风险与饮食因素之间的关联，所述饮食因素（a）与胰岛素水平正相关（即，精制谷物和血糖负荷）和（B）与胰岛素水平负相关（即，全谷物和纤维）。这些分析将在加州教师研究的背景下进行，包括117 646名妇女。在10年的随访期内（至2005年12月31日），预计在该队列中将诊断出154例乳头状甲状腺癌。癌症病例是通过与加州癌症登记处（CCR）的年度联系确定的，完成率超过99%。通过与参与者的联系和与各种数据库的链接，完成了对生命状态和继续加州居住的队列随访。使用经验证的食物频率调查问卷在基线时评估日常饮食摄入量。身高和体重在基线时自我报告，腰围和臀围在第一次随访时自我测量;这些测量值也在队列的子样本中与访谈者测量值进行了验证。将使用考克斯比例风险模型（以年龄为时间尺度并对出生队列进行调整）计算相对风险。这项研究的结果将对提高我们对这种不成比例地影响年轻女性的疾病的病因学的理解具有重要意义。

DESCRIPTION (provided by applicant): Over the past 10 years, the incidence of thyroid cancer in women has been increasing faster than any other cancer in either women or men. Yet its causes are still largely unknown, although several promising avenues related to nutrition have emerged. The proposed study will use previously collected, prospective data to verify and expand on these findings. In addition, we will address an emerging hypothesis regarding the impact of insulin on thyroid cancer risk. Our specific aims are: (1) to evaluate the relationship between papillary thyroid cancer risk and (a) cruciferous vegetables and isothiocyanates, using a newly developed database, and (b) overall and abdominal adiposity; and (2) to evaluate the association between papillary thyroid cancer risk and dietary factors that are (a) positively related to insulin levels (i.e., refined grains and glycemic load) and (b) inversely related to insulin levels (i.e., whole grains and fiber). These analyses will take place in the context of the California Teachers Study (CTS) and include 117,646 women. Over a ten- year follow-up period (through December 31, 2005), it is anticipated that 154 cases of papillary thyroid cancer will be diagnosed within this cohort. Cancer cases are identified through annual linkage with the California Cancer Registry (CCR) and are over 99% complete. Cohort follow-up for vital status and continued California residence is accomplished through contact with participants and linkage with various databases. Usual dietary intake was assessed at baseline using a validated food-frequency questionnaire. Height and weight were self-reported at baseline and waist and hip circumferences self-measured at the first follow-up; these measurements have also been validated against interviewer measurements in a subsample of the cohort. Cox proportional hazards models with age as the time scale and adjusting for birth cohort will be used to calculate relative risks. The results of this research will have important implications for improving our understanding of the etiology of this disease which disproportionately affects young women.