Abstract B023: Monoclonal gammopathy of undetermined significance and multiple myeloma survival among Hispanics living in Puerto Rico

Abstract

Abstract Background: Monoclonal Gammopathy of Undetermined Significance (MGUS) is a pre-malignant condition that may progress to multiple myeloma (MM). The aim of this study was to investigate the effect of previous MGUS diagnosis on MM survival. Methods: Data from the Puerto Rico Central Cancer Registry-Health Insurance Linkage Database were analyzed. The study included incident cases of MM diagnosed between 2010 and 2016. Patients with a previous MGUS diagnosis were identified through a claims-based algorithm. Competing-risk modeling was used to estimate the impact of previous MGUS on MM survival, adjusting for sex, age, comorbidity index, and insurance. The results were stratified by sociodemographic characteristics. Results: Of the 1,205 patients diagnosed with MM, 9.7% (n=117) had a previous diagnosis of MGUS. Patients with a previous MGUS diagnosis were found to be older, with a higher comorbidity index, and had Medicare compared to those without a previous MGUS diagnosis. Additionally, these patients were less likely to die from MM (SHR: 0.48, 95%CI=0.33-0.71) than those without a previous MGUS diagnosis. The magnitude of the association between MGUS and MM mortality varied by sociodemographic characteristics. For example, patients between 40-69 years with a previous MGUS diagnosis were less likely to die from MM (SHR:0.23, 95%CI=0.09-0.60) than those without MGUS. Patients with MGUS and ≤1 comorbidity index were also less likely to die from MM (SHR:0.31, 95%CI=0.18-0.55) than those without MGUS with the same comorbidity index. Males with MGUS were less likely to die from MM (SHR:0.41, 95%CI=0.22-0.73), but the association was weaker among females. Patients with MGUS and Medicare were less likely to die from MM (SHR:0.43, 95%CI=0.25-0.74) than those without MGUS who also had Medicare. No significant association was found between MGUS and MM mortality among patients with other insurance types, other age groups, and other comorbidities index. Conclusion: Findings show that males, younger adults, and those with low comorbidity may benefit from a prior MGUS diagnosis, indicating that patients with a previous MGUS diagnosis may have improved survival due to earlier access to more effective treatments for MM. Further research is necessary to gain a comprehensive understanding of the underlying mechanisms. Citation Format: Maira Castañeda-Avila, Tonatiuh Suárez-Ramos, Carlos R. Torres-Cintrón, Axel Gierbolini-Bermúdez, Karen J. Ortiz-Ortiz. Monoclonal gammopathy of undetermined significance and multiple myeloma survival among Hispanics living in Puerto Rico [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B023.