International comparison of treatment strategy and survival in metastatic gastric cancer.

BackgroundIn the randomized Asian REGATTA trial, no survival benefit was shown for additional gastrectomy over chemotherapy alone in patients with advanced gastric cancer with a single incurable factor, thereby discouraging surgery for these patients. The purpose of this study was to evaluate treatment strategies for patients with metastatic gastric cancer in daily practice in five European countries, along with relative survival in each country. MethodsNationwide population-based data from Belgium, Denmark, the Netherlands, Norway and Sweden were combined. Patients with primary metastatic gastric cancer diagnosed between 2006 and 2014 were included. The proportion of gastric resections performed and the administration of chemotherapy (irrespective of surgery) within each country were determined. Relative survival according to country was calculated. ResultsOverall, 15 057 patients with gastric cancer were included. The proportion of gastric resections varied from 81 per cent in the Netherlands and Denmark to 183 per cent in Belgium. Administration of chemotherapy was 392 per cent in the Netherlands, compared with 632 per cent in Belgium. The 6-month relative survival rate was between 390 (95 per cent c.i. 378 to 402) per cent in the Netherlands and 541 (521 to 569) per cent in Belgium. ConclusionThere is variation in the use of gastrectomy and chemotherapy in patients with metastatic gastric cancer, and subsequent differences in survival.