Do Medicare Claims Measure Cancer Relapse Patients: An External Validation Study

描述（由申请人提供）：2002年，医疗保险在新诊断的老年乳腺癌、结直肠癌和肺癌患者的化疗上花费了近10亿美元，但令人惊讶的是，人们对癌症化疗对这些患者的帮助或伤害程度知之甚少。这种令人不安的矛盾是由于在化疗临床试验中老年人的登记不足。在缺乏具有代表性的患者试验的情况下，治疗肿瘤学家、患者和政策制定者只能将在年轻和相对健康的个体中进行的临床试验的结果推断为一般癌症患者，这些患者往往年龄较大，有更大的合并症负担。这种常见外推的许多基本结果是未知的。例如，肿瘤学家甚至缺乏基本的观察性研究，报告老年结直肠癌（CRC）和乳腺癌患者在接受标准辅助化疗后的无病生存（DFS）。DFS是辅助化疗试验中最重要的终点之一，代表癌症复发或死亡的时间。因此，它与临床医生在常规护理环境中治疗患者有关。在这项应用中，我们的主要目的是确定观察性医疗保险管理数据是否可以用于准确测量老年结直肠癌和乳腺癌患者的DFS。如果发现它是准确的，DFS算法可能有意义地推进“老年人癌症”的研究，这越来越依赖于医疗保险数据来源。在我们的工作中，我们研究了两种类型的医疗保险患者，一种是在临床试验环境中接受辅助化疗的1539名老年乳腺癌和结直肠癌患者的高选择性队列，另一种是在常规护理环境中接受相同部位和阶段特异性癌症的1250名老年患者的低选择性队列，名义上接受相同的辅助化疗。通过研究这两个不同的队列，我们特别承认，在临床试验队列中表现良好的有效DFS算法可能在常规护理患者中表现不佳，这些患者构成了美国大多数癌症患者，并且是大量基于老年癌症的观察性医疗保险研究的焦点。如果我们发现DFS可以在医疗保险数据中精确测量，我们将提供一个关键的工具来加速与老年人癌症相关的几个领域的研究。在这些类型的研究成果中，将有一个更清晰的理解：(1)与临床试验人员和治疗医生相关的试验疗效与有效性；(2)不同治疗方法应用于日常护理老年患者的临床疗效（CE）；(3)癌症护理模式；(4)提供的护理质量；(6)老年人特定化疗方案的成本和收益。对于后者，如果一种疗法不能延长DFS，或者确实加速了死亡，医疗保险管理人员将需要重新考虑其报销。开发准确的DFS算法是扩展我们现有工作的前提，该工作检查了常规护理老年患者癌症化疗的风险和益处，这在一定程度上涉及上述所有领域。

DESCRIPTION (provided by applicant): Medicare spent nearly a billion dollars in 2002 on chemotherapy for newly diagnosed elderly breast, colorectal, and lung cancer patients, but surprisingly little is known about the extent to which cancer chemotherapies help or harm such patients. This unsettling paradox is the result of the well-described under- enrollment of the elderly on the clinical trials of chemotherapy. In the absence of trials with representative patients, treating oncologists, patients, and policy-makers are left to extrapolate results of clinical trials conducted in younger and comparatively healthier individuals to the general population with cancer, who tend to be older and have greater comorbid disease burdens. Many basic results of this common extrapolation are unknown. For example oncologists lack even basic observational studies reporting the disease-free survival (DFS) of elderly colorectal (CRC) and breast cancer patients following receipt standard adjuvant chemotherapy. DFS is one of the MOST important end-points in adjuvant chemotherapy in trials, representing the time to cancer relapse or death. Thus, it is relevant to clinicians treating patients in the usual care setting. In this application, our broad aim is to determine whether observational Medicare administrative data may be used to accurately measure DFS in elderly patients with CRC and cancer breast. If it is found to be accurate, the DFS algorithm may meaningful advance research in "cancer in the elderly" which increasing relies on Medicare data sources. In our work, we study two types of Medicare patients, a highly select cohort of 1,539 elderly breast and CRC patients who were treated with adjuvant chemotherapy in the clinical trial setting and a less select patient cohort of 1,250 elderly patients with the same site and stage-specific cancers and treated with nominally identical adjuvant chemotherapy, but in the usual care setting. By studying these two disparate cohorts, we specifically acknowledge that a valid DFS algorithm that performs well in the clinical trial cohort may not perform well in usual care patients, who form the majority of cancer patients in the United States and who are the focus of a wealth of observational Medicare-based studies of cancer in the elderly. If we find that DFS can be accurately measured in Medicare data, we will provide a critical tool to accelerate research in several fields relevance to cancer in the elderly. Among the fruits of these types of the research will be a clearer understanding of (1) trial efficacy vs. effectiveness which is relevant to both clinical trialists and treating physicians; (2) the clinical effectiveness (CE) of different therapies applied to usual care elderly patients; (3) the patterns of cancer care; (4) the quality of care delivered; and (6) the cost and benefit of specific chemotherapy regimens in the elderly. Regarding the latter, if a therapy does not extend DFS or indeed if it accelerates death, Medicare administrators would need to revisit its reimbursement. Developing an accurate DFS algorithm is a predicate to extending our existing work that examines the risks and benefits of cancer chemotherapy in usual care elderly patients, which touches, to some extent, on all area noted above.