title: Epidemiological study of colorectal adenoma and cancer in symptomatic patients in China between 1990 and 2009.
abstract: OBJECTIVE
  The best cure for colorectal cancer (CRC) lies on its early diagnosis and treatment. We aimed to provide the epidemiological features of advanced colorectal adenoma (A-CRA) and CRC in symptomatic patients and to determine whether the incidences of A-CRA and CRC increased simultaneously in China between 1990 and 2009.
  
  
  METHODS
  A total of 157,943 patients who had undergone a colonoscopy from 1990 to 2009 were enrolled, of which 6,777 patients had A-CRA and 3,503 had CRC. They were compared with controls in a stratified analysis. The detection rates of A-CRA and CRC in the 1990s and 2000s were also compared.
  
  
  RESULTS
  The detection rate of A-CRA increased 1.88-fold over the two decades, while that of CRC increased 0.66-fold. The percentages of patients with A-CRA and CRC who were elder than 50 years were significantly higher in the 2000s than those in the 1990s (P = 0.000). The changes of location of A-CRA and CRC during the two decades indicated a shift of lesions from the distal colon to proximal colon.
  
  
  CONCLUSIONS
  There was a significant increase in detection rate of A-CRA in the 2000s, but CRC did not increase at a similar speed. Our results indicated that the early detection and removal of colorectal adenoma in symptomatic patients might decrease the incidence of CRC.
authors.affiliation: Department of Gastroenterology, Renji Hospital, Shanghai Jiaotong University School of Medicine Shanghai Institute of Digestive Disease, Shanghai.
authors.forename: Hui Min
authors.initials: HM
authors.lastname: Chen
authors.forename: Yu Rong
authors.initials: YR
authors.lastname: Weng
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
authors.forename: Jian Qiu
authors.initials: JQ
authors.lastname: Sheng
authors.forename: Ping
authors.initials: P
authors.lastname: Zheng
authors.forename: Cheng Gong
authors.initials: CG
authors.lastname: Yu
authors.forename: Jing Yuan
authors.initials: JY
authors.lastname: Fang
mesh_terms: D000236:Adenoma / Q000453:epidemiology*; D000328:Adult; D000368:Aged; D002681:China / Q000453:epidemiology; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013997:Time Factors