Differences in the management and survival of metastatic colorectal cancer in Europe. A population-based study.

BACKGROUND The management regarding metastatic colorectal cancer throughout Europe is not well known. AIMS To draw a European comparison of the management and prognosis of metastatic colorectal cancers. METHODS Factors associated with chemotherapy administration were identified through logistic regressions. Net survival was estimated and crude probabilities of death related to cancer and other causes using a flexible cumulative hazard model. RESULTS Among the 13 227 patients with colorectal cancer diagnosed between 2010 and 2013 in cancer registries from 10 European countries, 3140 were metastatic. 62% of metastatic patients received chemotherapy. Compared to Spain, the related adjusted odds ratios ranged from 0.7 to 4.0 (P<0.001) according to country. The 3-year net survival by country ranged between 16% and 37%. The survival gap between countries diminished from 21% to 10% when adjusting for chemotherapy, age and sex. Geographical differences in the crude probability of death related to cancer were large for patients <70 or ≥80 years at diagnosis. CONCLUSION Heterogeneity in the application of European guidelines partly explain these differences. General health between populations, accessibility to a reference centre, or provision of health care could also be involved. Further population-based studies are warranted to disentangle between these possible explanations.