Colonoscopy: Practice Patterns and Limitations

描述(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直肠癌筛查的首选选择，通过息肉切除术，它可以移除癌前病变，并可能治愈早期癌症。尽管筛查结肠镜检查有积极的作用，但由于结肠镜检查后间歇性癌症的发生，目前人们对结肠镜检查的准确性提出了担忧。息肉摘除后的随访程序似乎也被相对过度使用。关于结肠镜检查的使用和结果，基于人群的数据相对较少。拟议的研究将包括两个部分，一个使用无癌症人群，另一个使用发生结直肠癌的患者。在第一阶段，将通过5%的随机抽样医疗保险索赔数据来确定接受结肠镜检查并切除息肉的患者队列。之前的索赔将根据结肠息肉或其他风险因素或结肠手术的既往病史进行搜索以进行分层。在索引息肉切除术后，将对索赔进行审查，以确定重复结肠镜检查和其他结肠镜检查的时间和结果，特别是在3年最小间隔之前进行结肠镜检查。实践模式将在患者、医生和设施的特点之间进行比较。在第二阶段，首次诊断为结直肠癌的患者将通过SEER登记文件进行识别。在含有早期癌症的息肉患者中，内窥镜切除的治疗结果将与手术切除进行比较，并将评估延迟的结果，包括后续手术的必要性。预测使用内窥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，将搜索先前声称的数据，以确定结肠镜检查的使用。将根据患者、医生、设施和小区域特征确定潜在漏诊或间歇性癌症患者的队列，并将其与其他患者进行比较。本申请中提出的研究将提供有关结肠镜检查在常规实践中的使用和潜在有效性的重要数据。鉴于普通人群越来越重视结肠镜检查作为首选的筛查检查，这些数据将有助于未来的政策决策。与公共健康相关：结直肠癌是美国第二致命的癌症，基本上可以通过切除息肉来预防。然而，在常规的临床实践中，人们对大肠息肉的治疗和转归知之甚少。利用大量联邦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，评估其在早期结直肠癌治疗中的有效性，并估计结肠镜检查潜在的漏检率。

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.