Trends in primary central nervous system lymphoma incidence and survival in the U.S

Area of Science:

• Neuro-oncology
• Epidemiology
• Immunology

Background:

• Primary central nervous system lymphoma (PCNSL) incidence may be increasing in immunocompetent populations.
• Understanding trends requires excluding cases from immunocompromised individuals, such as those with human immunodeficiency virus (HIV) or transplant recipients.

Purpose of the Study:

• To estimate PCNSL incidence and survival trends specifically among immunocompetent individuals.
• To analyze the impact of HIV and transplant status on PCNSL rates and outcomes.

Main Methods:

• Utilized data from 10 Surveillance, Epidemiology and End Results (SEER) cancer registries (1992-2011).
• Excluded cases with reported HIV infection or death due to HIV.
• Estimated transplant recipient cases using the Transplant Cancer Match Study.
• Analyzed PCNSL trends and survival stratified by HIV status and age.

Main Results:

• PCNSL rates in the general population were significantly influenced by immunosuppressed cases, especially in younger men.
• Among immunocompetent individuals, PCNSL incidence increased significantly in men and women aged 65+ years (1.7% and 1.6% per year, respectively).
• PCNSL rates remained stable in other age groups among the immunocompetent.
• Five-year survival for PCNSL was poor overall (9.0% for HIV-infected cases).
• Five-year survival for HIV-uninfected cases improved from 19.1% (1992-1994) to 30.1% (2004-2006).

Conclusions:

• PCNSL incidence has risen among immunocompetent elderly adults but not younger adults.
• Survival for PCNSL patients, both HIV-infected and HIV-uninfected, remains poor.
• The declining HIV prevalence in PCNSL cases impacts overall population trends.