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

描述(由申请人提供)：2002年，Medicare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。这种令人不安的悖论是众所周知的老年人在化疗临床试验中登记人数不足的结果。在缺乏有代表性患者的试验的情况下，治疗肿瘤学家、患者和政策制定者只能将在较年轻和相对健康的个人中进行的临床试验的结果推断到一般癌症患者，这些人往往较年长，并有更大的并存疾病负担。这种常见外推的许多基本结果都是未知的。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)和乳腺癌患者接受标准辅助化疗后的无病生存率(DFS)。DFS是试验中辅助化疗最重要的终点之一，代表癌症复发或死亡的时间。因此，这与临床医生在通常的护理环境中治疗患者有关。在这项应用中，我们的广泛目标是确定是否可以使用观察性医疗保险管理数据来准确测量患有结直肠癌和乳腺癌的老年患者的DFS。如果它被发现是准确的，DFS算法可能会有意义地推进“老年人癌症”的研究，这种癌症的增加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，一组是高度精选的1,539名老年乳腺癌和结直肠癌患者，他们在临床试验环境中接受了辅助化疗，另一组是较少选择的1,250名老年患者，他们患有相同部位和特定阶段的癌症，接受了名义上相同的辅助化疗，但在通常的护理环境中接受了治疗。通过研究这两个不同的队列，我们明确承认，在临床试验队列中表现良好的有效DFS算法在常规护理患者中可能表现不佳，这些患者构成了美国大多数癌症患者，他们是大量基于联邦医疗保险的老年癌症观察性研究的焦点。如果我们发现DFS可以在医疗保险数据中准确地衡量，我们将提供一个关键工具来加快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，将更清楚地了解(1)试验疗效与与临床试验者和治疗医生有关的有效性；(2)对日常护理的老年患者应用不同疗法的临床效果(CE)；(3)癌症护理的模式；(4)提供的护理质量；以及(6)特定化疗方案在老年人中的成本和效益。关于后一种情况，如果一种治疗方法不能延长DFS，或者确实如果它加速了死亡，联邦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，该工作检查了在日常护理的老年患者中癌症化疗的风险和好处，这在某种程度上涉及到上述所有领域。

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.