title: [The incidence differences among sex, geographical areas and mean age of diagnosis for liver cancer in China, 1989-2008].
abstract: OBJECTIVE
  Using the incidence data from 1989 to 2008 of liver cancer from population in cancer registration areas in China, the differences and changes of gender, urban and rural areas for liver cancer incidence in different years were studied, and the mean age of incidence was analyzed.
  
  
  METHODS
  The incidence data of liver cancer from National Cancer Registration database were sorted and checked. A total of 181 097 new liver cancer cases were collected, covering 711 843 051 person years from 1989 to 2008.Using Poisson regression model, Stratified by gender and areas, changes of incidence gender ratio, ratio of urban and rural, and mean age were analyzed.
  
  
  RESULTS
  After adjusting the age, the liver cancer incidence in male was about 3 times higher than that in females (ranging from 2.64-3.54), and the ratio change between male and female for the 20 years did not have statistically significant (P = 0.150). The incidence ratio between urban and rural areas has increased from 0.51 in 1989 to 0.61 in 2008 (P < 0.01). The mean ages of diagnosis for male and female increased from 57.14 years to 60.34 years, 61.69 years to 66.47 years, respectively from 1989 to 2008. The mean age of liver cancer diagnosis has increased in the 20 years (P < 0.01).
  
  
  CONCLUSIONS
  The liver cancer incidence between male and female did not change significantly among 20 years. The difference of liver cancer incidence between urban and rural areas has reduced, and the mean age of diagnosis was deferred.
authors.affiliation: National Cancer Center, National Center for Cancer Registries, Beijing 100021, China.
authors.forename: Siwei
authors.initials: S
authors.lastname: Zhang
authors.affiliation: National Cancer Center, National Center for Cancer Registries, Beijing 100021, China.
authors.forename: Rongshou
authors.initials: R
authors.lastname: Zheng
authors.affiliation: National Cancer Center, National Center for Cancer Registries, Beijing 100021, China.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zeng
authors.affiliation: National Cancer Center, National Center for Cancer Registries, Beijing 100021, China. Email: chenwq@cicams.ac.cn.
authors.forename: Wanqing
authors.initials: W
authors.lastname: Chen
mesh_terms: D017668:Age of Onset; D000368:Aged; D002681:China; D005260:Female; D006801:Humans; D015994:Incidence; D008113:Liver Neoplasms / Q000453:epidemiology*; D008297:Male; D012042:Registries; D012424:Rural Population; D014505:Urban Population