title: The prevalence of colorectal neoplasia in patients with gastric cancer: a Korean Association for the Study of Intestinal Disease (KASID) Study.
abstract: OBJECTIVE
  The goal of this study was to determine the prevalence of colorectal neoplasia, using colonoscopy surveillance, in a cohort of patients with gastric cancers.
  
  
  BACKGROUND
  The association between gastric cancer and colorectal cancer has been conflicting.
  
  
  METHODS
  A total of 543 patients (males, 362; females, 181) with gastric cancer were matched with 2 persons from the population without a diagnosis of gastric cancer as confirmed by endoscopy according to age (+/-2 y), sex, date of colonoscopy examination (+/-2 wk), and endoscopist. Main Outcome was the prevalence of colorectal neoplasia diagnosed by colonoscopy.
  
  
  RESULTS
  A significantly higher colorectal cancer prevalence was found in the gastric cancer group, that is, 19 of 543 (3.5%) versus 14 of 1086 (1.3%; P<0.001). The odds of developing colorectal cancer were higher in the presence of gastric cancer (odds ratios, 3.46; 95% confidence interval: 1.51-7.91). Four of the 119 (3.4%) gastric cancer patients below 50 years of age had colorectal cancer in contrast with no cases in the matched controls. The prevalence of colorectal adenoma was higher in the gastric cancer group, with a prevalence of 215 in 543 (39.6%) versus 311 in 1086 (28.6%; P<0.001). The risk of adenoma was also greater among gastric cancer patients (odds ratios, 1.76; 95% confidence interval: 1.34-2.25).
  
  
  CONCLUSIONS
  Our data reveal a higher prevalence and risk of colorectal cancer in patients diagnosed with gastric cancer, particularly in patients below 50 years of age. Additional studies are needed to explore the geographical differences in the association between gastric cancer and colon cancer.
authors: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, South Korea.
authors: Dong Il
authors: DI
authors: Park
authors: Seung Ha
authors: SH
authors: Park
authors: Tae Woo
authors: TW
authors: Yoo
authors: Hyun Soo
authors: HS
authors: Kim
authors: Suk-Kyun
authors: SK
authors: Yang
authors: Jeong-Sik
authors: JS
authors: Byeon
authors: Bong Min
authors: BM
authors: Koh
authors: Jin Oh
authors: JO
authors: Kim
authors: Ki-Nam
authors: KN
authors: Shim
authors: Yoon Tae
authors: YT
authors: Jeen
authors: Bo In
authors: BI
authors: Lee
authors: Kyu Yong
authors: KY
authors: Choi
authors: Hang Lak
authors: HL
authors: Lee
authors: Dong Soo
authors: DS
authors: Han
authors: Ilhyun
authors: I
authors: Baek
authors: Cheol Hee
authors: CH
authors: Park
authors: Seun Ja
authors: SJ
authors: Park
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology; D000367:Age Factors; D000368:Aged; D016022:Case-Control Studies; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology; D004724:Endoscopy; D005260:Female; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary; D015995:Prevalence; D011446:Prospective Studies; D013274:Stomach Neoplasms / Q000473:pathology*