title: Altering trend of clinical characteristics of colorectal cancer: a report of 3,607 cases.
abstract: OBJECTIVE
  Incidence of colorectal cancer in China has increased since 1980s. The epidemiologic character of colorectal cancer in China is similar to that in high prevalence districts. The distributions among different regions are different, with high incidence in the Eastern coastal regions and low incidence in the Western inland. This study was to explore the clinical characteristics of colorectal cancers in Heilongjiang province in 1981-2005.
  
  
  METHODS
  A total of 3607 patients with pathologically confirmed colorectal cancer who were hospitalized to Tumor Hospital of Harbin Medical University, Heilongjiang province, in 1981-2005 were divided into 5-year groups. Their clinical data were analyzed.
  
  
  RESULTS
  The annual hospitalization number of colorectal cancer patients in 1985-2005 was increased by 8.5%. The median age increased by seven years. There was no significant change in the male to female ratio of the patients. The proportion of rectal cancer decreased by 13.6%, while the proportions of both right and left hemi-colon cancers increased by 6.8%; the proportion of colorectal cancer at Dukes' A increased by 3.8%, while the proportion of colorectal cancer at Dukes' D decreased by 8.1%.
  
  
  CONCLUSIONS
  In the past 25 years, the incidence of colorectal cancer has increased in Heilongjiang province with an increase in median age; the male to female ratio has no significant change. The incidence of rectal cancer and proportion of Dukes' A cancer have increased.
authors.affiliation: Department of Colorectal Surgery, Tumor Hospital, Harbin Medical University, Harbin, Heilongjiang, PR China.
authors.forename: Shi-Xiong
authors.initials: SX
authors.lastname: Jiang
authors.forename: Xi-Shan
authors.initials: XS
authors.lastname: Wang
authors.forename: Chang-Hui
authors.initials: CH
authors.lastname: Geng
authors.forename: Gui-Yu
authors.initials: GY
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D013997:Time Factors