Presentation (CTI)

OBJECTIVES: Radiographic screening for gastric cancer (GC) has been a national program in Japan since 1983. Endoscopic screening was added in 2016, and approximately half of all the municipalities have already introduced it. Since the implementation of cancer screening is entrusted to local municipalities, regional differences exist in the adoption of endoscopic screening, even at the prefecture level. Nationwide, the incidence and mortality rates of GC have decreased over the past decade, but the impact of endoscopic screening remains unclear. The impact of endoscopic screening was evaluated in the Fukui Prefecture where endoscopic screening was introduced simultaneously across all municipalities in 2016.
METHODS: The incidence and mortality rates of GC were assessed before and after the introduction of endoscopic screening in the Fukui Prefecture. Age-standardized rates (ASRs) for individuals under 75 years were calculated using annual reports of the national vital statistics and cancer registry. The pre-introduction period was defined as 2011 to 2015, and the post-introduction period as 2016 to 2020. Annual percentage decreases were compared for all causes, all cancers along with GC mortality and incidence rates.
RESULTS: After 2016, the ASRs of GC incidence decreased steeply, while the ASRs of GC mortality gradually declined after 2016. The annual percentage decrease in GC incidence was observed as 2.0% during the pre-introduction period and 5.2% during the post-introduction period. The annual percentage decrease for GC mortality was changed from 3.6% to 5.6%. Although the annual percentage decrease in all-cause mortality rates was similar between the two periods, it was larger in all cancer mortality in the post-introduction period.
CONCLUSIONS: In the Fukui prefecture, a more rapid decrease in gastric cancer mortality has been observed following the introduction of endoscopic screening, suggesting its potential effectiveness. However, the long-term impact should be reevaluated, considering the time-lag effect associated with cancer screening.