We aimed to present the temporal and geographical trends in the incidence of stomach cancer in Golestan province, a high-risk area in Northern Iran. :

This cross-sectional study was conducted on stomach cancer cases from Golestan province during 13-year (2004-2016). Data on stomach cancer cases were obtained from the Golestan Population-based Based Cancer Registry (GPCR). Age-Standardized Incidence Rates (ASR) per 100,000 person-year were calculated by CanReg5 software. The Joinpoint regression analysis was used to assess the temporal trends in incidence rate of stomach cancer.

Overall, 2964 new cases of stomach cancer were registered in the GPCR during the study period.The number of new cases of stomach cancer increased by 22.33% (from 215 in 2004 to 263 in 2016), of which 18.14%, 25.12% and -20.93% were due to population size, population aging and risk, respectively. The ASR of stomach cancer was significantly higher in men (26.93) than women (12.16) (p-value<0.01). Our results showed decreasing trends in incidence of stomach cancer in Golestan men (from 31.99 in 2004 to 26.26 in 2016). The ASRs of stomach cancer in women were 11.36 and 12.18 in 2004 and 2016, respectively. We found a higher ASR of stomach cancer in rural (21.38) than urban (18.14) (p-value=0.03) population. Our findings suggested higher risk for stomach cancer in Eastern parts of Golestan province, especially Kalaleh city.

Our results emphasized high incidence rates of stomach cancer in Golestan province of Iran. We found temporal and geographical diversities in incidence rates of stomach cancer in this high-risk population. Further studies are warranted to determine the risk factors related to these trends.