Explaining gastric cancer survival differences among European countries.

Wide geographic variability in incidence and mortality rates for gastric cancer exists throughout the world despite persistent decreases over several decades. Variability in survival from gastric cancer is also evident and countries with higher incidence rates of gastric cancer show better survival rates than countries with lower incidence. The aim of this study was to identify reasons for the association between incidence and survival and to obtain survival estimates and differences corrected for this variation, thus facilitating further interpretation by clinical factors such as stage and treatment. Relative survival rates for gastric cancer derived from the EUROCARE-2 database for 47 cancer registries in 17 European countries were analyzed with regression methods to adjust differences by age, sex, period of diagnosis, subsite of the stomach, histologic type and stage at diagnosis. Overall, nearly 60% of the variability in gastric cancer relative survival was explained by differences in these variables. Factors are related to treatment and general management of patients is expected to explain the residual variability in gastric cancer survival between European countries. There is a need to improve completeness and standardization of detailed information collected on gastric cancer patients to allow detailed comparative analyses and interpretation. Copyright 2004 Wiley-Liss, Inc.