[Trends of stomach cancer incidence and mortality in Shandong province from 2012 to 2012 and predictions from 2023 to 2030].

Objective: We aimed to analyse the trend of incidence and mortality of stomach cancer in Shandong province from 2012 to 2022 and predict the development trend from 2023 to 2030. Methods: Data on incidence and mortality of stomach cancer in Shandong province from 2012 to 2022 were obtained from Shandong Cancer Registry. The incidence, age-specific incidence, mortality and age-specific mortality in different years, sexes and urban and rural areas were calculated, the rates were standardized based on the age composition of the Chinese standard population in 2000. The average annual percent change (AAPC) of incidence and mortality was calculated using Joinpoint software. The Bayesian age-period-cohort model was used to predict the trend of stomach cancer incidence and mortality from 2023 to 2030. Results: From 2012 to 2022, the stomach cancer age-standardized incidence rate (ASIR) and age-standardized mortality rate (ASMR) showed a decreasing trend. The ASIR decreased from 27.47/100 000 in 2012 to 16.06/100 000 in 2022 (AAPC=-5.10%, P＜0.001), and the ASMR decreased from 17.69/100 000 to 11.09/100 000 (AAPC=-5.52%, P＜0.001). The ASIR and ASMR of male, female, urban and rural population also showed downward trends. The incidence and mortality rates of men were always higher than those of women, and the difference between urban and rural areas is gradually narrowing. In 2022, the ASIR (16.09/100 000 in urban and 16.03/100 000 in rural) and the ASMR (11.10/100 000 in urban and 11.08/100 000 in rural) of stomach cancer between urban and rural areas were nearly identical. The Bayesian age-period-cohort model predicted that the ASIR of stomach cancer in Shandong would further decrease from 2023 to 2030 (AAPC=-0.51%, P=0.001), but the change tended to be smooth. The incidences in male (AAPC=-1.46%, P=0.010) and rural areas (AAPC=-1.21%, P＜0.001) were still expected to have a little room for decline. The trend of incidences in female and urban areas were not statistically significant. The trend of mortality was consistent with the incidence. Conclusions: The stomach cancer incidence and mortality in Shandong shows a decreasing trend and it is expected to decrease further by 2030. However, the trend tends to be smooth, and the disease burden should be reduced as early as possible for high-risk population and high-risk factors of stomach cancer.