Distribution of primary site of hepatic metastases and prognosis of hepatic metastases at different primary sites

Abstract

Background Most of the time, the primary tumor of hepatic metastases is easy to find. However, sometimes this is a confusing question. The present study aimed to explore the distribution of primary sites of hepatic metastases and the prognosis of hepatic metastases at different primary sites. Methods Data on patients with hepatic metastases were obtained from the surveillance, epidemiology, and end results (SEER) database between 2010 and 2016. Descriptive statistics was used to analyze the distribution of primary sites, life table to calculate survival rate, Kaplan-Meier method to plot survival curves, and Cox univariate regression and multivariate regression analysis to assess prognostic factors. Results The median age of 151,821 patients was 67 years; 58.7% of the primary sites were derived from the digestive system, followed by the respiratory system (25.6%) and other sites (15.8%). Ten leading primary sites were lung (25.4%), colorectum (24.1%), pancreas (19.8%), stomach (4.5%), breast (4.1%), gallbladder and biliary system (3%), esophagus (2.7%), kidney and renal pelvis (2.1%), ovary (1.8%) and primary sites unknown (2%). The overall survival probability of patients with hepatic metastases at 6 months, 1 year, and 3 years was 44.5%, 28.7%, and 9.9%, respectively, with a median survival of 4 months. The prognosis of hepatic metastases from lymphoma (Hodgkin and non-Hodgkin), the small intestine, breast, and colorectum was relatively better, and that from primary sites unknown, urinary system (bladder, urethra), lung, and pancreas was quite poor. Conclusion The distribution of primary sites of hepatic metastases was different under different grouping conditions, but the lung, colorectum and pancreas were the top three sources. The prognosis of hepatic metastases from different primary sites varied greatly.