Background: Gastric cancer often presents in a metastasized stage. We conducted a population-based study to evaluate trends in systemic treatment and survival of metastatic noncardia gastric cancer.
Patients and methods: All patients with noncardia adenocarcinoma of the stomach, diagnosed between 1990 and 2011 in the Eindhoven Cancer Registry area in the Netherlands were included (N = 4797). We conducted multivariable logistic regression analysis to evaluate trends in administration of palliative chemotherapy and multivariable proportional hazards regression analyses to evaluate trends in crude overall survival.
Results: The proportion of patients presenting with metastatic gastric cancer increased from 24% in 1990 to 44% in 2011 (P < 0.0001). The use of palliative chemotherapy increased, from 5% in 1990 to 36% in 2011, with a strong increase in particular after 2006 (P < 0.0001). Younger patients [<50 years: adjusted odds ratio (ORadj) 3.9, P < 0.001; 50-59 years: ORadj 1.7, P = 0.01] and patients with a high socioeconomic status (ORadj 1.7, P = 0.01) more often received chemotherapy. In contrast, older patients (70-79 years: ORadj 0.3, P < 0.001; 80+ years: ORadj 0.02, P < 0.001), patients with comorbidity (ORadj 0.6, P = 0.03), linitis plastica (ORadj 0.5, P = 0.03) and multiple distant metastases (ORadj 0.5, P = 0.01) were less often treated with chemotherapy. A large hospital variation was observed in the administration of palliative chemotherapy (9%-27%). Median overall survival remained constant between 15 [95% confidence interval (CI) 11.9-17.7] and 17 (95% CI 15.0-20.0) weeks (P = 0.10).
Conclusions: The increased administration of chemotherapy in patients with metastatic gastric cancer did not lead to an increase in population-based overall survival. Identification of the subgroup of patients which benefits from palliative chemotherapy is of utmost importance to avoid unnecessary treatment.
Keywords: chemotherapy; gastric cancer; hospital variation; metastasis; survival.