The prognostic analysis of different metastatic patterns in advanced liver cancer patients: A population based analysis

BACKGROUND: The prognostic impact of different distant metastases pattern in liver cancer is unexplored still now. The aim of this study is to analyze the metastasis patterns and prognosis differences for patients with stage IV liver cancers. METHODS: A SEER analysis was performed. Overall survival and cancer-specific survival were calculated by the Kaplan-Meier method. Multivariable Cox regression models were used to further analyze survival outcome and other prognostic factors. RESULTS: A total of 37526 eligible cases were retrieved in the Surveillance, Epidemiology, and End Results database. Among these patients, stage of IV liver cancer accounted for 14.80% (5555/37526) at initial diagnosis. Patients who suffered bone, brain or lung metastasis occupied 55.61% (3089/5555). Comparing with other two single metastases, the patients with brain metastasis exhibited worst overall survival whose mean of survival was 4.758 months. Multivariate analysis with Cox hazard regression model showed that metastatic site was an independent prognostic factor of overall survival and cancer-specific survival in patients with single metastasis (P<0.05). The results of univariate analysis showed that metastatic pattern was significantly correlated with overall survival (P = 0.038) and cancer-specific survival (P = 0.035) of patients with two sites. CONCLUSIONS: Lung was the most common site of single metastasis for liver cancers. Patients with bone metastasis had best survival outcome comparing with other two distant metastases. Patients with two metastatic sites, where one of them is the lung tends to have a slight trend to a worse outcome.