Non-Hodgkin Lymphoma – Nodal and Extranodal: 20-Year Comparative Mortality, Survival & Biologic Behavior Analysis by Age, Sex, Race, Stage, Cell Morphology/Histology, Cohort Entry Time-Period and Disease Duration: A Systematic Review of 384,651 Total NHL Cases Including 261,144 Nodal and 123,507 Extranodal Cases for Diagnosis Years 1975-2016: (SEER*Stat 8.3.6)
Authors: Milano Anthony F. 
Published: September 2023

During the past 5 decades, there have been reports of increases in the incidence and mortality rates of non-Hodgkin lymphoma (NHL) in the United States and globally. The ability to address the epidemiologic diversity, prognosis and treatment of NHL depends on the use of an accurate and consistent classification system. Historically, uniform treatment for NHL has been hampered by the lack of a systematic taxonomy of non-Hodgkin lymphoma. Before 1982, there were 6 competing classification schemes with contending terminologies for NHL: the Rappaport, Lukes-Collins, Kiel, World Health Organization, British, and Dorfman systems without consensus as to which system is most satisfactory regarding clinical relevance, scientific accuracy and reproducibility and presenting a difficult task for abstractors of incidence information. In 1982, the National Cancer Institute sponsored a workshop1 that developed a working formulation designed to: 1) provide clinicians with prognostic information for the various types of NHLs, and 2) provide a common language that might be used to compare clinical trials from various treatment centers around the world. Studies imply that prognosis is dependent on tumor stage and histology rather than the primary localization per se.2 This study utilizes the National Cancer Institute PDQ adaptation of the World Health Organization’s (WHO) updated REAL (Revised European American Lymphoma) classification3 of lymphoproliferative diseases, and the SEER*Stat 8.3.6 database (released Aug 8, 2019) for diagnosis years 1975-2016. In this article, we make use of 40 years of data to examine patterns of incidence, survival and mortality, and selected cell bio-behavioral characteristics of NHL in the United States.

Objective. —To update trends in incidence and prevalence in the United States of non-Hodgkin lymphoma, examine, compare and contrast short and long-term patterns of survival and mortality, and consider the outcome impacts of anatomic location of NHL nodal and extranodal subdivisions, utilizing selected ICD-O-3 histologic oncotypes stratified by age, sex, race/ethnicity, stage, cell behavioral morphology and histologic typology, cohort entry time-period and disease duration, employing the statistical database of the National Cancer Institute SEER*Stat 8.3.6 program for diagnosis years 1975-2016.4

Methods.— A retrospective, population-based cohort study using nationally representative data from the National Cancer Institute’s (NCI) Surveillance, Epidemiology, and End Results (SEER) program to evaluate 384,651 NHL cases for diagnosis years 1975-2016 comparing multiple variables of age, sex, race, stage, cell behavioral morphology, cohort entry time-period, disease duration and histologic oncotype. Relative survival statistics were analyzed in two cohorts: 1975-1995 and 1996-2016. Survival statistics were derived from SEER*Stat Database: Incidence – SEER 9 Regs Research Data, November 2018 Submission (1975-2016) &lt;Katrina/Rita Population Adjustment&gt; released April 2019, based on the November 2018 submission.

Results.— Incidence rates, relative frequency distributions, survival and mortality by age, sex, stage and cell behavioral morphology, of adult nodal (N) and extranodal (EN) NHL in 2 entrant time-periods as recorded in the SEER Program of the National Cancer Institute for diagnosis years 1975-2016 (SEER Stat 8.3.6) are summarized. Shifts in trends over time are identified, and the findings are correlated with prognosis, including short and long-term observed (actual), expected and relative survival, median observed and relative survival, mortality rates and excess death rates per 1000 people.

Conclusions.— Trends in SEER incidence, prevalence, survival and mortality by age, sex, race, stage, cell behavioral morphology, cohort entry time-period, relative frequency and percent distribution, were examined to provide a current epidemiologic and medical-actuarial risk assessment framework for nodal (N) and extranodal (EN) non-Hodgkin’s lymphoma in the 1975-2016 timeframe.