Incidence trends of gastroenteropancreatic neuroendocrine tumors in the United States from 1975 to 2012.

Abstract

231 Background: Although multiple studies document a rise in gastroenteropancreatic neuroendocrine tumor (GEP-NET) incidence over the past several decades, there are limited national data regarding recent trends. Using a population-based registry, we evaluated GEP-NET incidence trends in the US population from 1975-2012 by age and calendar year at diagnosis and year of birth. Methods: GEP-NET cases between 1975-2012 were identified from the most recent version of the Surveillance, Epidemiology, and End Results (SEER) registry based on histologic and site codes. We calculated overall annual incidence, age-adjusted incidence (number of cases per 100,000), annual percent change (APC), and average APC by 5 year age intervals. We also evaluated the incidence rates by age, period, and birth year cohorts. Results: We identified 22,744 patients with GEP-NETs. In adults age 25-39 years, GEP-NET incidence rates declined from the mid 1970s to early 1980s, then increased until 2012 (Table 1). In adults age 40 and older and between ages 15-24 years, incidence rates generally increased continuously from 1975 to 2012. Adults age 40-69 years demonstrated the most rapid increases in average APC, approximately 4-6% per year. Overall incidence rates were highest in adults age 70-84 years. Since the late 1880s, GEP-NET incidence has increased in consecutive birth cohorts. Conclusions: Our study demonstrates that more recent generations have had higher incidence rates than more distant generations. In addition, GEP-NETs are more common among older adults and the number of GEP NETs has increased in past decades. [Table: see text]