Determinants of overall survival of young adults with multiple myeloma: A National Cancer Database (NCDB) analysis of years 2004-2017.
Authors: Chaulagain Chakra Pani , Saba Ludovic , Liang Hong , Dominguez Barbara , Fu Chieh Lin 
Published: June 2023

8052 Background: There is paucity of real-world data on the outcomes of younger patients with multiple myeloma (MM). In this IRB approved retrospective analysis, the NCDB was used to evaluate the determinants of overall survival (OS) of young adults ≤ 50 years with MM who were treated at commission on cancer (CoC) accredited facilities across the USA. Methods: Using the NCDB, we identified N = 16,792 patients ≤ 50 years old diagnosed and treated for MM from 2004 to 2017. Multivariable cox regression analysis with backward elimination was utilized to identify the independent survival factors, using significance level of p < 0.05. Kaplan-Meier survival curves were generated and SAS version 9.4 was used to analyze the data. Results: Overall median survival time was 119 months; while survival rates of 1, 3, and 5-year were 90.6%, 78.0%, and 67.8%, respectively. Multivariable cox regression analysis with backward elimination method revealed that there were 13 significant independent survival factors: age, sex, race, ethnicity, Charlson-Deyo score, insurance status, facility type, median income, education level, distance to facility, year of diagnosis, hematopoietic stem-cell transplantation (HSCT), and treatment-regimen. Male patients were more likely to die compared to female patients (HR = 1.22, p < 0.0001). Black patients were predicted to have less death events compared to White patients (HR = 0.91, p = 0.004). In addition to that, Hispanic patients were more likely to die compared to non-Hispanics (HR = 1.2, p = 0.0006). Subjects who were treated in non-academic facilities were more likely to die compared to the ones who received care in academic centers (HR = 1.2, p < 0.0001). Moreover, patients with Medicare (HR = 1.65, p < 0.0001), Medicaid (HR = 1.49, p < 0.0001), and no insurance (HR = 1.63, p < 0.0001) had higher chance of death compared to those with private insurance. Patients with lower income < $38,000 were more likely to die compared to income ≥ $63,000 (HR = 1.19, p = 0.0007). Only 6.8% of patients underwent HSCT and 93.2% did not. Patients undergoing HSCT had worse OS compared to those treated without HSCT (HR = 0.36, p < 0.0001). Detailed analysis will be presented. Conclusions: In this large cohort of real-world data analysis of very young MM patients, we found that White and Hispanic patients age ≤ 50 years had significantly inferior survival compared to Black and non-Hispanic patients. Patients with lower income, lower education level, non-private insurance, and those without access to academic centers for MM care had worse survival outcomes. The findings can be useful for designing prospective studies addressing disparity and equitable access to MM care. Despite being a pivotal part of MM therapy, HSCT utilization in the real-world setting is minimal. The barriers to HSCT utilization and the reason why it is inferior to no-HSCT in real-world setting need to be identified and addressed.