title: Epidemiology of metastatic hepatocellular carcinoma, a nationwide perspective.
abstract: BACKGROUND
  Hepatocellular carcinoma (HCC) is the most common primary tumor of the liver.
  
  
  OBJECTIVE
  The aim of this study was to describe the prevalence, trends, and predictors of metastatic HCC on a national scale.
  
  
  METHODS
  We used two nationwide datasets for our study: the University Health Consortium (UHC) and the Nationwide Inpatient Sample (NIS) databases. We included adults with a primary diagnosis of HCC from 2000 to 2011. We collected information regarding demographics, insurance, HCC risk factors, liver decompensation, and the sites and frequencies of metastases. Multivariable regression analysis was used to examine predictors of metastatic HCC. Trend analysis was performed to examine the change in metastatic HCC prevalence over time.
  
  
  RESULTS
  We included 25,671 and 26,054 HCC patients from UHC and NIS, respectively. Prevalence of metastatic HCC was 18 % with lung being the most frequent site (31 %). Compared with Caucasian, African American ethnicity was an independent predictor of metastasis in both the NIS [OR 1.13 (1.02-1.25)] and UHC [OR 1.4 (1.3-1.6)] databases. Lack of long-term insurance was associated with significantly higher prevalence of metastasis in both the NIS [OR 1.6 (1.4-1.9)] and UHC [OR 1.9 (1.6-2.2)] databases. There has been an increased prevalence of metastatic HCC over the last decade with an annual percentage change of +1.25 and +1.60 % (p = 0.03 and p = 0.08) for the NIS and UHC databases, respectively.
  
  
  CONCLUSIONS
  Metastasis is not rare among HCC patients and is rising in prevalence over the last decade. Lungs were the most common metastatic site. Ethnicity and insurance status are independent predictors of metastasis.
authors.affiliation: Department of Internal Medicine, Shands Hospital, University of Florida, 1600 SW Archer Road, PO BOX 100277, Gainesville, FL, 32610, USA, Ali.Abbas@medicine.ufl.edu.
authors.forename: Ali
authors.initials: A
authors.lastname: Abbas
authors.forename: Sabeen
authors.initials: S
authors.lastname: Medvedev
authors.forename: Nathan
authors.initials: N
authors.lastname: Shores
authors.forename: Lydia
authors.initials: L
authors.lastname: Bazzano
authors.forename: Ahmed
authors.initials: A
authors.lastname: Dehal
authors.forename: Jay
authors.initials: J
authors.lastname: Hutchings
authors.forename: Luis
authors.initials: L
authors.lastname: Balart
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D014481:United States / Q000453:epidemiology