title: Distribution of a single nucleotide polymorphism of insulin-like growth factor-1 in colorectal cancer patients and its association with mucinous adenocarcinoma.
abstract: OBJECTIVE
  To analyze the difference in the distribution of an insulin growth factor-1 (IGF-1) polymorphism (-2995 C/A) between young and old colorectal cancer (CRC) patients.
  
  
  METHODS
  Information from 950 CRC patients undergoing surgery at the Taipei Veterans General Hospital between 2000 and 2005 was collected. The IGF-1 polymorphism was analyzed in patients in extreme age ranges at the time of CRC onset (i.e., under the 20th and above the 80th percentiles, respectively). Associations between clinicopathological variables and the IGF-1 polymorphism were analyzed.
  
  
  RESULTS
  Young CRC patients had a higher frequency of advanced disease (58.7%) and mucinous adenocarcinoma (20%) than old CRC patients. Among old CRC patients, the frequency of the AA genotype of IGF-1 was 12.7% (24/189), which was significantly higher than in young patients (4.2%). Other clinicopathological factors including tumor location, differentiation, lymphovascular invasion, and TNM stage were not associated with the AA genotype of IGF-1. Mucinous differentiation (but not the other clinicopathological factors) was significantly associated with the CA/AA genotype of IGF-1 (39/195).
  
  
  CONCLUSIONS
  Older patients had a higher frequency of the AA genotype of IGF-1(-2995 C/A), while younger patients more often had advanced disease and mucinous adenocarcinoma.
authors.affiliation: Division of Colon and Rectal Surgery, Department of Surgery, Taipei Veterans General Hospital, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Jen-Kou
authors.initials: JK
authors.lastname: Lin
authors.forename: Ming-Yin
authors.initials: MY
authors.lastname: Shen
authors.forename: Tzu-Chen
authors.initials: TC
authors.lastname: Lin
authors.forename: Yuan-Tzu
authors.initials: YT
authors.lastname: Lan
authors.forename: Huann-Sheng
authors.initials: HS
authors.lastname: Wang
authors.forename: Shung-Haur
authors.initials: SH
authors.lastname: Yang
authors.forename: Anna Fen-Yau
authors.initials: AF
authors.lastname: Li
authors.forename: Shih-Ching
authors.initials: SC
authors.lastname: Chang
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000453:epidemiology / Q000235:genetics*; D017677:Age Distribution; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000235:genetics*; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic
chemical_list: D007334:Insulin-Like Growth Factor I