Colonoscopy: Practice Patterns and Limitations

描述（由申请人提供）：结肠镜检查被许多专业和非专业团体认为是结肠直肠癌筛查的首选方法，由于息肉切除术，它可以去除癌前病变，并可能治愈早期癌症。尽管结肠镜筛查具有积极的作用，但由于结肠镜检查后可发生间隔期癌症，人们对目前结肠镜检查的准确性提出了担忧。在息肉切除后的随访中，似乎也存在相对过度使用的情况。关于结肠镜检查的使用和结果，基于人群的数据相对缺乏。拟议的研究将包括两个组成部分，一个使用无癌症人群，另一个使用突发结直肠癌患者。在第一阶段，将通过5%的医疗保险索赔数据随机抽样确定一组接受结肠镜检查并切除息肉的患者。将根据既往结肠息肉史或其他危险因素或结肠手术对先前的索赔进行搜索以进行分层。在指数息肉切除术后，将对患者进行检查，以确定重复结肠镜检查和其他结肠手术的时机和结果，特别关注在最小间隔3年之前进行的结肠镜检查。实践模式将比较病人，医生和设施的特点。在第二阶段，首次诊断为结直肠癌的患者将通过SEER注册文件进行识别。在包含早期癌症的息肉患者中，内镜切除治疗的结果将与手术切除治疗的结果进行比较，并测量延迟结果，包括后续手术的需要。预测使用内镜切除的因素将被确定，治疗倾向评分将被开发并用于比较结果。在所有发生癌症的患者中，将检索先前的索赔数据以确定结肠镜检查的使用。一组潜在漏诊或间隔期癌症患者将被确定，并根据患者、医生、设施和小区域特征与其他患者进行比较。本应用程序中提出的研究将为结肠镜检查在常规实践中的使用和潜在有效性提供重要数据。鉴于结肠镜检查在普通人群中越来越受到重视，这些数据将有助于为未来的政策决策提供信息。公共卫生相关性：结肠直肠癌是美国第二大致命癌症，在很大程度上可以通过切除息肉来预防。然而，在常规的临床实践中，对结肠直肠息肉的治疗和预后的认识有限。利用大量医疗保险患者的数据，我们将研究通过结肠镜切除息肉的实践模式，评估其在治疗早期结直肠癌中的有效性，并估计结肠镜检查的潜在漏检率。

DESCRIPTION (provided by applicant): Colonoscopy is considered by many professional and lay groups to be the preferred option for colorectal cancer screening and by virtue of polypectomy, it allows removal of premalignant lesions and possibly curative treatment of early stage cancers. Despite the positive attributes of screening colonoscopy, because of development of interval cancers following colonoscopy, concerns about the accuracy of colonoscopy as currently practiced have been raised. It also appears that there is relative overuse of the procedure for follow up after polyp removal. There is a relative paucity of population-based data regarding colonoscopy utilization and outcomes. The proposed study will include two components, one using a cancer-free population and one using patients with incident colorectal cancer. In the first phase, a cohort of patients undergoing colonoscopy with polypectomy will be identified through a 5% random sample of Medicare claims data. Previous claims will be searched to stratify according to a prior history of colon polyps or other risk factors, or colonic surgery. Following the index polypectomy, claims will be examined to determine the timing and outcome of repeat colonoscopy and other colonic procedures, with a particular focus on colonoscopies performed before the 3-year minimum interval. Practice patterns will be compared between patient, physician and facility characteristics. In the second phase, patients with a first diagnosis of colorectal cancer will be identified through SEER registry files. Among patients with a polyp containing early stage cancer, the outcome of treatment with endoscopic resection will be compared to surgical resection, and delayed outcomes, including the need for subsequent surgery will be measured. Factors that predict the use of endoscopic resection will be identified and propensity scores for treatment will be developed and used to compare outcomes. Among all patients with incident cancer, prior claims data will be searched to determine the use of colonoscopy. A cohort of patients with potentially missed or interval cancer will be identified and compared to other patients according to patient, physician, facility, and small area characteristics. The studies proposed in this application will provide important data about the use and potential effectiveness of colonoscopy in routine practice. Given the increased emphasis on colonoscopy as a preferred screening test in the general population, these data will help inform future policy decisions. PUBLIC HEALTH RELEVANCE: Colorectal cancer, the second most fatal cancer in the U.S., is largely preventable through the removal of polyps. However, there is only limited knowledge about the treatment and outcome of colorectal polyps in routine clinical practice. Using data from a large number of Medicare patients, we will study practice patterns for polyp removal via colonoscopy, evaluate its effectiveness in the treatment of early stage colorectal cancer, and estimate the potential failed detection rate at colonoscopy.