Primary cerebral lymphoma' characteristics, incidence, survival, and causes of death in the United States

Abstract

Purpose: This study aimed to provide an updated overview of primary central lymphoma (PCL) using a large cohort of 33 years. That being said, we attempted to examine the patient demographics, management plans and their outcome, causes of death and the time trends in overall incidence and mortality rates of these patients.

Methods: We conducted a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER) database between 1983 and 2016. We calculated the frequencies and the average annual age-adjusted rate (AAR) of PCL patients. Uni- and multivariable accelerated failure time regression were used to identify possible prognostic factors affecting the patients' survival. Furthermore, detailed causes of death were extracted and joint point regression analysis was done to examine incidence and mortality trends.

Results: We identified 2925 PCL cases. The AAR was 0.148 per 100,000. An increase in age was significantly associated with shorter survival (HR: 1.01, 95%CI = 1.01-1.01, P < .001), while a recent year of diagnosis after 1993-2002 and 2002 was associated with improved survival (HR: 0.76, CI = 0.65-0.89, P = .001), and (HR: 0.48, CI = 0.41-0.56, P < .001), respectively. Overall, the trend of mortality rates in PCL patients has declined over the past years (-1.38% per year).

Conclusion: Our results support the previous evidence by showing an increase in patients' survival over time. While most PCL-related deaths occur within the first year, subsequent slow progression was observed after the first few years of survival. More attention should be given to the other possible non-PCL causes of death, especially beyond ten years of survival.

Keywords: Causes of death; Incidence; PCL; Primary cerebral lymphoma; SEER; Survival.