Rates of early mortality in acute promyelocytic leukemia patients: A SEER-based study.

e18500 Background: Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia (AML) that often presents with overt bleeding, thrombocytopenia, and coagulopathy. Prior to the use of anthracyclines and the development of all-trans-retinoic acid (ATRA), APL was known to be a fatal condition with high levels of early mortality. Although APL treatments have evolved over the years, early mortality only mildly decreased in the 1990s-2000s after introduction of ATRA therapy. There are limited studies evaluating the trends in early mortality rate of APL in recent years. Methods: Data was collected from the Surveillance Epidemiology and End Results (SEER) database using 17 registries from the years of 2000-2021. Selection criteria included diagnosis of APL with SEER-specific cause of death identified as death attributable to this cancer diagnosis. Early mortality (EM) in this population was defined as death within 30 days of diagnosis. Multivariate regression analysis was conducted using R-studio to calculate odds ratios (ORs) adjusted for covariates including age group, sex, race, and level of income. Joinpoint regression analysis was used to calculate the annual percentage change (APC) of early mortality for the selected time period. Results: Preliminary analysis of 5,200 patients, 2,617 males and 2,583 females, showed an overall early mortality rate (EMR) of 19.10% from the years of 2000-2021. Men were at higher odds of EM (OR = 1.20). White (N= 2,853), Hispanic (N= 1,304), Black (N= 546), and Asian or Pacific Islander (N = 442) patients comprised a majority of the study population. There was a statistically significant lower odds of EM in Hispanic (0.780, 95% CI 0.65-0.92, p = 0.0046), Black (0.750, 95% CI 0.59-0.96, p = 0.024), and Asian or Pacific Islanders (0.750, 95% CI 0.57-0.98, p = 0.045). There was a statistically significant decrease in EMR from 2000 to 2018 (27.85% vs 11.62% p = 1.62e-5). EMR significantly increased from 2018 to 2020 (11.62% vs 19.31%, p = 0.013) and 2021 (11.62% vs 20.07%, p = 0.006). Age adjusted Joinpoint analysis indicated a negative APC of EM between the years 2000-2018 (-5.22%, p=0.010), but showed a positive APC of EM (25.6%, p=0.049) from 2018-2021. Overall, EMR did not significantly change from 2000 and 2021 (p=0.061). Conclusions: Early mortality attributable to APL initially decreased between 2000-2018. There has been a statistically significant increase in EMR in this population from 2018-2021. Our study suggests that EMR remains high in APL despite advances in medical therapies and technology. It is possible that the COVID-19 pandemic may have contributed to the rise in EMR in this population, as EMR was shown to significantly increase from 2018 to 2020 and 2021. Further studies are needed to investigate the factors leading to this observation.