Gastric cancer: a case study in Turkey.

Objective: The aim of this study was to determine age-specific incidence ratios, gastric cancer localization trend, histologic subtype and cancer related survival that whether have changed during the period from 1999 to 2010.

Materials And Methods: A total of 866 gastric cancer patients treated at the hospital were retrospectively evaluated. Categorical and continuous variables were summarized using descriptive statistics and were compared using the Chi-square and Mann-Whitney U-tests, respectively. Cancer related survival rates were estimated by the Kaplan-Meier method.

Results: The median age at diagnosis was 58 years. Trends concerning the median ages of the patients were increased (from 57 years to 59 years). The proportion of diffuse histological subtype gastric adenocarcinoma increased during the period from 1999 to 2010, and it was 27% between 1999 and 2002 and 32% between 2007 and 2010 (P = 0.04). The proportion of gastric adenocarcinoma localized in cardia increased during the period from 1999 to 2010, and was 7.2% between 1999 and 2002; and 22.5% in 2007 and 2010 (P = 0.004). For stage I that was diagnosed between 1999 and 2002, the relative survival was 67% and in patients diagnosed between 2007 and 2010 the rate was 85%. For stage II that was diagnosed between 1999 and 2002, the relative survival was 35% and in patients diagnosed between 2007 and 2010, the rate was 65%. Cox regression analysis was conducted based on age subgroup, diagnosis time, and gastric localization (proximal/distal) and for adenocarcinoma subtypes. Hazard ratio was 31.6 for stage IV (confidence interval [CI] = 10-42), 1.3 for cardia localization (CI = 1.04-1.6) and 1.37 for patients who had been diagnosed between 1999 and 2002 (1.14-1.78).

Conclusions: The ratio of median age at diagnosis and proximal gastric adenocarcinoma, diffuse histologic subtype increased between 1999 and 2010. Cancer related survival significantly improved for stage I and stage II. Cardia localization and time of diagnosis between 1999 and 2002 had significantly poor outcome on relative survival.