Five-year survival analysis of gastric cancer from population-based cancer registration data in Zhejiang province, China

Abstract

Objective: To analyze epidemiology of gastric cancer five-year survival distribution in Zhejiang population-based cancer registration. Methods: The follow-up data of registrated gastric cancer cases diagnosed from 2008 to 2019 in 22 national cancer registry areas of Zhejiang Province were collected and divided into three diagnostic periods: 2008-2011, 2012-2015 and 2016-2019 to calculate five-year observed survival rates (OSRs), five-year relative survival rates (RSRs) and five-year age-standardized relative survival rates (ARSRs). The distribution of population characteristics (including gender, urban/rural, age group and occupation) and clinical characteristics (including the highest diagnostic institution, sub-site, pathological type and degree of differentiation) of gastric cancer survival rates in each period were analysed. Results: 51 663 new cases of gastric cancer in 2008-2019 in the cancer registration area of Zhejiang Province were included in the analysis, and the ARSR of gastric cancer in 2008-2011, 2012-2015 and 2016-2019 showed an increasing trend (39.2%, 41.3% and 44.7%, respectively). In 2016-2019, the ARSR was similar across gender and urban and rural areas (44.4% for men and 45.7% for women; 44.9% in urban areas and 44.2% in rural areas); Among people with different occupations, the ARSR was highest among business and service workers (55.3%), the agriculture, forestry, animal husbandry and fisheries, water conservancy production workers and domestic workers were lower (41.5% and 43.2%, respectively). The highest diagnostic institution was the provincial hospital with a higher gastric cancer survival rate (47.0%) than the municipal (43.4%) and district (43.6%) levels. The ARSR for gastric cancer was relatively high in the lesser curvature (59.7%), pylorus (50.4%), antrum (49.3%), and greater curvature (48.7%), and lowest in cardia (38.9%). Among the major pathological types, adenocarcinoma (NOS) had an ARSR of 48.1%, mucinous adenocarcinoma 41.3%, imprinted cell carcinoma 39.4%, and squamous carcinoma 33.4%. The ARSR for highly differentiated, moderately differentiated, poorly differentiated and undifferentiated gastric cancers were 80.6%, 57.9%, 43.2% and 36.8%, respectively. Conclusion: The 5-year survival rate of gastric cancer in Zhejiang Province is high and on the rise, with similar survival rates in different genders, urban and rural areas, and significant differences in the survival rates of gastric cancer patients with different occupational groups, highest diagnostic institutions, tumour sub-sites, pathological types and differentiation degrees.