Mortality-related risk factors and long-term survival after 4460 liver resections in Sweden-a population-based study

The objectives of this study were to analyze the outcome after hepatectomy and to identify contributing factors to mortality and long-term survival in a population-based setting.

A retrospective, nationwide register study was performed. All patients who underwent hepatectomy in Sweden between 2002 and 2011 were identified in the Swedish Hospital Discharge Registry using their unique personal identification numbers. This cohort was linked to the National Cancer Registry (cancer diagnosis), the National Registry of Causes of Death, and the Migration Registry. Survival analysis by Kaplan-Meier method was performed to assess long-term outcome. A Cox regression model was used to analyze risk factors affecting long-term survival.

Overall, 4460 hepatectomies were performed. The 30- and 90-day mortalities were 1.8 and 3.1 %, respectively. The overall 5- and 10-year survival rates for all diagnoses were 45 and 38 %, respectively. Independent risk factors for 5-year mortality were as follows: patient age, comorbidity, male gender, intrahepatic/extrahepatic cholangiocarcinoma, gallbladder cancer, extent of hepatectomy, and hepatectomies performed at non-university hospitals. Re-resection (78.1 % with diagnosis "metastasis") was performed on 374 patients. In these patients, mortality risk decreased by >50 % (HR 0.42; 95 %, CI 0.33-0.53).

In a population-based analysis, liver resections are done with a low mortality risk and good long-term outcome. Patients who underwent resection at a University Hospital showed a significant better outcome compared to patients resected at non-University Hospitals. These results support further centralization of liver surgery. Re-resection should be performed if feasible.