Regional and inter-hospital differences in the utilisation of liver surgery for patients with synchronous colorectal liver metastases in the Netherlands

BACKGROUND: The objective of this study was to map referral patterns in patients with synchronous colorectal liver metastases (SCLM) and to investigate if type, volume and location of the hospital of diagnosis are associated with whether or not patients underwent liver resection. METHODS: This population-based study includes all patients diagnosed with SCLM between 2008 and 2012, based on the Netherlands Cancer Registry. To study inter-hospital variation, the proportion of patients undergoing liver surgery was calculated per hospital of diagnosis. Multivariable multilevel logistic regression analysis was used to investigate the association between hospital characteristics and liver resection. RESULTS: Of 10,520 patients with SCLM, 12% (n = 1259) underwent liver surgery. Of these patients, 58% (n = 733) were referred to another hospital to undergo liver surgery. In 53% of the patients (n = 647), liver resection was performed in a university hospital, in 39% (n = 482) in a dedicated liver centre and in 8% (n = 102) in a general hospital. There was a large inter-hospital variation in the proportion of patients undergoing liver resection (2-26%). In a multilevel logistic regression model, the odds of undergoing liver surgery were higher when patients were diagnosed in hospitals where liver surgery was performed compared with the general hospitals (dedicated liver centre: odds ratio 1.36 [95% confidence intervals 1.08-1.70], university hospital: odds ratio 1.69 [95% confidence intervals 1.22-2.34]). CONCLUSION: There is a large inter-hospital and inter-regional variation in the utilisation of liver resection. Patients diagnosed with SCLM in expert centres had a higher chance of undergoing liver resection