Trend breaks in incidence of non-cardia gastric cancer in the Netherlands

Introduction: The incidence of gastric cancer declined over the past decades. Recently, unfavorable trend breaks (i.e. rise in incidence) were seen for non-cardia cancer in younger age groups in the US. It is unclear whether these also occur in other Western countries. We aimed to analyze the gastric cancer incidence trends by age, sex, subsite and stage in the Netherlands. Methods: Data on all patients with gastric adenocarcinoma diagnosed from 1973 to 2011 (n=9093) were obtained from the population-based Eindhoven cancer registry. Incidence time trends (European standardized rates per 100,000) were separately analyzed by sex, age group (<60, 60-74, and >75 years), subsite, and pathological stage. Joinpoint analyses were performed to discern trend breaks, age-period-cohort analyses to examine the influence of longitudinal and cross-sectional changes. Results: The incidence of non-cardia cancer declined annually by 3.5% (95% CI -3.8; -3.3). However, in males <60 years, the incidence flattened since 2006, and tended to rise in those >74 years. This pertained to corpus cancers. The incidence of cardia cancer peaked in 1985 and decreased subsequently by 2.4% (95% CI -3.2; -1.5) yearly. The absolute incidence of stage IV disease at first diagnosis initially decreased, but then remained stable over the past 15-20 years. Conclusions: The incidence of non-cardia cancer declined over the past four decades in the Netherlands, but now seems to be stabilizing particularly in males. Unfavorable trend breaks are seen for corpus cancer in younger and older males. The trend breaks in the Netherlands are however not similar to those observed in the US.