Abnormal Fecal Test Results Associated with Colorectal Cancer Incidence and Mortality

项目摘要/摘要 结直肠癌(CRC)是美国癌症相关死亡的第二大常见原因 (美国)。美国预防服务工作组已经建立了几种筛查模式，以早期发现 例如粪便免疫化学试验(FIT)和粪便潜血试验(FOBT)。FIT和FOBT是 美国常用的筛查工具。异常时必须在FIT/FOBT之后进行结肠镜检查 评估癌前病变和结直肠癌病变。文献稀少，结果多种多样。 关于以多快的速度完成后续工作的建议。研究提出了一个最佳的窗口 在异常FIT/FOBT后6个月至24个月的诊断性随访结果各不相同。 此外，研究主要来自台湾和以色列的国际人口。目前，只有 美国的一项研究调查了时间对结肠镜检查和结直肠结果的影响。仅限本研究 看的是结直肠癌的发病率和诊断分期，而不是结直肠癌死亡率。此外，研究人群是 仅限于加利福尼亚州。总体而言，未能完成诊断结肠镜检查与 异常的FIT/FOBT对CRC结果的影响还没有得到广泛的研究。我们的研究将使用国家 退伍军人事务部(VA)提供的电子健康记录和基于索赔的数据，以解决关键问题 通过评估诊断性结肠镜检查和多个结直肠癌终点之间的关系，发现文献中的空白。 首先，我们将研究暴露与未暴露的个体罹患偶发和致命性结直肠癌的风险。 用于诊断异常FIT/FOBT后的结肠镜检查(目标1)。接下来，我们将确定时间对 在接受诊断性结肠镜检查的个体中，结肠镜检查对结直肠癌发病率、诊断阶段、 和致命性癌症(目标2)。最后，我们将描述社会人口学和临床的程度 变量(如查尔逊合并症、年龄、种族)影响异常FIT/FOBT后的诊断完成 筛选试验(目标3)。

PROJECT SUMMARY/ABSTRACT Colorectal cancer (CRC) is the second most common cause of cancer-related mortality in the United States (US). The US Preventive Services Task Force has instituted several modes of screening for early detection of CRC, such as the fecal immunochemical test (FIT) and fecal occult blood tests (FOBT). FIT and FOBT are common screening tool used in the US. FIT/FOBT must be followed by diagnostic colonoscopy when abnormal to evaluate for precancerous and cancerous colorectal lesions. The literature is scarce and has varied results on recommendations for how quickly to complete follow-up time. Studies suggesting an optimal window for diagnostic follow-up vary their recommendations from 6 months to 24 months after abnormal FIT/FOBT. Additionally, studies mainly came from international populations in Taiwan and Israel. Currently, there was only one US study examining the effect of time to diagnostic colonoscopy and colorectal outcomes. This study only looked at CRC incidence and stage of diagnosis, and not CRC mortality. Additionally, the study population was limited to the state of California. Overall, the relationship between failure to complete diagnostic colonoscopy after an abnormal FIT/FOBT on CRC outcomes has not been widely studied. Our study will use national electronic health records and claims-based data from the Department of Veterans Affairs (VA) to address key gaps in the literature by evaluating the relationship between diagnostic coloscopy and multiple CRC endpoints. First, we will examine the risk for incident and fatal CRC cancer among individuals exposed versus unexposed to diagnostic colonoscopy after abnormal FIT/FOBT (Aim 1). Next, we will determine the effect of time to colonoscopy, among individuals exposed to diagnostic colonoscopy, on CRC incidence, stage at diagnosis, and fatal cancer (Aim 2). Lastly, we will characterize the extent to which sociodemographic and clinical variables (e.g. Charlson comorbidity, age, race) impact diagnostic completion after an abnormal FIT/FOBT screening test (Aim 3).