Determining the clinical significance of monoclonal gammopathy of undetermined si

描述(由申请人提供)：多发性骨髓瘤(MM)之前均有未确定意义的单克隆性伽马病(MGUS)。虽然MGUS的生物学意义已经确定，但其临床意义仍有待确定。MGUS通常是在患者体检时偶然发现的，这些患者的体征或症状暗示着MM和相关的恶性肿瘤。MGUS的患病率很高(50岁以上和70岁以上的人分别为3%和5%)，但转化为MM和相关恶性肿瘤的风险非常低(考虑到相互竞争的死因，每年为0.4%)。然而，专家建议对MGUS患者进行无限期的年度体检和实验室测试随访，即使目前没有可用的治疗方法可以防止恶变，也没有证据表明这种随访有助于更好的临床结果。事实上，随访可能会因为癌症预期而给患者带来心理痛苦，可能会给医疗保健系统带来巨大的经济负担(2008年有360万人患有MGU)，并可能减少获得癌症护理的机会(美国临床肿瘤学会预测，到2020年将缺少4000名血液肿瘤学家)。因此，必须明确MGUS的临床意义。为了实现这一目标，并利用监测流行病学和最终结果(SEER)计划和相关的医疗保险数据，我们的研究有两个具体目标。在目标1中，我们将确定MM和相关恶性肿瘤患者的总体和疾病特异性生存率是否存在差异，这些患者出现从头开始的症状，以及那些先前诊断为MGUS的患者。在目标2中，我们将比较这两组患者的主要癌症并发症(高钙血症、骨折和依赖透析的肾病)的发生率。在目标3中，我们将确定各种MGUS随访策略对临床结果的影响。我们将使用监测流行病学和最终结果(SEER)计划和相关的医疗保险数据。

DESCRIPTION (provided by applicant): Multiple myeloma (MM) is uniformly preceded by monoclonal gammopathy of undetermined significance (MGUS). While the biological significance of MGUS has been established, its clinical significance has yet to be determined. MGUS is generally discovered incidentally during the work-up of patients with signs or symptoms suggestive of MM and related malignancies. The prevalence of MGUS is high (3% and 5% of people age over 50 and 70 years, respectively), but the risk of transformation to MM and related malignancies is very low (0.4% per year after taking into account competing causes of death). Yet experts recommend indefinite annual follow- up of MGUS patients with physical examinations and laboratory tests, even though no currently available treatment can prevent malignant transformation and no evidence exists to suggest that such follow-up contributes to better clinical outcomes. In fact, follow-up may cause psychological distress to patients due to cancer anticipation, may represent an enormous economic burden on the health care system (3.6 million people in 2008 harboring MGUS), and may decrease access to cancer care (shortfall of 4000 hematologist- oncologists by 2020 projected by the American Society of Clinical Oncology). Therefore, the clinical significance of MGUS must be determined. Toward that goal, and utilizing the Surveillance Epidemiology and End Results (SEER) program and the linked Medicare data, our study has 2 specific aims. In Aim 1, we will determine whether there is a difference in overall and disease-specific survival between patients with MM and related malignancies who presented de novo and those who had a preceding diagnosis of MGUS. In Aim 2, we will compare the rates of major cancer complications (hypercalcemia, bone fracture, and dialysis- dependent kidney disease) between these 2 groups. In Aim 3, we will determine the impact of various MGUS follow-up strategies on clinical outcome. We will use the Surveillance Epidemiology and End Results (SEER) program and the linked Medicare data.