title: Contributions of Subtypes of Non-Hodgkin Lymphoma to Mortality Trends.
abstract: BACKGROUND
  Non-Hodgkin lymphoma (NHL) comprises distinct tumor subtypes. Although mortality from NHL overall has changed dramatically in the United States over time, little is known about trends for subtypes, because death certificates do not record this information.
  
  
  METHODS
  Using data from U.S. Surveillance, Epidemiology, and End Results (SEER) areas, we assessed NHL mortality rates and mapped NHL deaths to incident NHL cases in SEER cancer registries. This allowed us to evaluate population-level mortality trends attributed to specific NHL subtypes (incidence-based mortality; IBM). We also describe NHL incidence and survival after NHL diagnosis by calendar year. We used Joinpoint to identify years when IBM and incidence rate trends changed slope.
  
  
  RESULTS
  Overall NHL mortality rates increased during 1975-1997, peaking at 10.9 per 100,000 person-years, then decreased subsequently in 1997-2011. Overall IBM rates mirror this trend during 1990-2011. For B-cell NHL subtypes, IBM rates decreased beginning in the mid-1990s, with yearly declines of -3.0% for diffuse large B-cell lymphoma (DLBCL), -2.7% for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), and -5.3% for follicular lymphoma. Incidence rates for these subtypes did not decrease until after 2003. Corresponding 5-year cancer-specific survival increased dramatically over time for DLBCL (from 37%-66%), CLL/SLL (69%-84%), and follicular lymphoma (69%-82%). IBM for peripheral T-cell lymphoma was flat during 2006-2011, although incidence increased.
  
  
  CONCLUSIONS
  Mortality due to three common B-cell NHL subtypes has fallen over time in the United States.
  
  
  CONCLUSIONS
  This decline reflects better survival after NHL diagnosis, likely from improved therapies, because the decline in NHL incidence occurred later.
authors.affiliation: Surveillance Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, Maryland. Department of Epidemiology and Biostatistics, The George Washington University Milken Institute School of Public Health, Washington DC. howladern@mail.nih.gov.
authors.forename: Nadia
authors.initials: N
authors.lastname: Howlader
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland.
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Morton
authors.affiliation: Surveillance Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, Maryland.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Feuer
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland. Université Paris Sud, Faculté de Médecine Paris Sud, Le Kremlin-Bicêtre, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Besson
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland.
authors.forename: Eric A
authors.initials: EA
authors.lastname: Engels
mesh_terms: D000328:Adult; D000367:Age Factors; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality*; D008224:Lymphoma, Follicular / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality*; D016411:Lymphoma, T-Cell, Peripheral / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality*; D009026:Mortality / Q000639:trends*; D009367:Neoplasm Staging; D011379:Prognosis; D018426:SEER Program; D015996:Survival Rate; D014481:United States / Q000453:epidemiology