Evaluating population-level outcomes in Chronic Lymphocytic leukemia in the era of novel therapies using the SEER registry

In the last decade, novel agents such as BTK and BCL-2 inhibitors have revolutionized treatment of CLL/SLL, with clinical trials showing improved overall survival compared to chemotherapeutic agents. However, studies examining whether they have improved overall survival at the population level are lacking. We evaluated this by conducting a retrospective analysis of CLL/SLL patients registered in the National Cancer Institute's surveillance epidemiology and end results (SEER) database, analyzing overall survival (OS) in periods pre- and post-availability of novel agents, along with demographic information. Our results showed that median OS significantly improved over time [7.8 years (2000-2005), 9.1 years (2006-2013), and not reached (2014-2018) (p<0.001)]. Compared to diagnosis in 2014-2018, diagnosis in earlier periods was associated with higher mortality risk (2000–2005-HR 1.39, 95% CI 1.28-1.37, p<0.001: 2006–2013-HR 1.09, 95% CI 1.06-1.13, p<0.001). Lower mortality risk was seen in patients age <85 years whereas median household income of <$75000 was associated with higher mortality. Our study provides real-world data suggesting a possible multifactorial contribution to improvement in survival, including availability of novel agents, better monitoring, and supportive care. They also show discrepancies in overall survival for CLL patients due to socioeconomic status and demographic factors.