title: ABO blood type, long-standing diabetes, and the risk of pancreatic cancer.
abstract: OBJECTIVE
  To retrospectively study pancreatic cancer patients with respect to their ABO blood type and diabetes.
  
  
  METHODS
  Our analysis included a cohort of 1017 patients with pancreatic ductal cancer diagnosed at our hospital in Tokyo. They were divided into two groups: 114 patients with long-standing type 2 diabetes (DM group, defined as diabetes lasting for at least three years before the diagnosis of pancreatic cancer) and 903 patients without diabetes (non-DM group). Multivariate analysis was performed to identify factors that are associated with long-standing diabetes. The DM group was further divided into three subgroups according to the duration of diabetes (3-5 years, 5.1-14.9 years, and 15 years or more) and univariate analyses were performed.
  
  
  RESULTS
  Of the 883 pancreatic cancer patients with serologically assessed ABO blood type, 217 (24.6%) had blood type O. Compared with the non-DM group, the DM group had a higher frequency of blood type B [odds ratio (OR) = 2.61, 95%CI: 1.24-5.47; reference group: blood type A]. Moreover, male (OR = 3.17, 95%CI: 1.67-6.06), older than 70 years of age (OR = 2.19, 95%CI: 1.20-3.98) and presence of a family history of diabetes (OR = 6.21, 95%CI: 3.38-11.36) were associated with long-standing type 2 diabetes. The mean ages were 64.8 ± 9.2 years, 67.1 ± 9.8 years, and 71.7 ± 7.0 years in the subgroups with the duration of diabetes, 3-5 years, 5.1-14.9 years, and 15 years or more, respectively (P = 0.007). A comparison of ABO blood type distribution among the subgroups also showed a significant difference (P = 0.03).
  
  
  CONCLUSIONS
  The association of pancreatic cancer with blood type and duration of diabetes needs to be further examined in prospective studies.
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, Tokyo 113-8677, Japan. naoto_egawa@tmhp.jp
authors.forename: Naoto
authors.initials: N
authors.lastname: Egawa
authors.forename: Yingsong
authors.initials: Y
authors.lastname: Lin
authors.forename: Taku
authors.initials: T
authors.lastname: Tabata
authors.forename: Sawako
authors.initials: S
authors.lastname: Kuruma
authors.forename: Seiichi
authors.initials: S
authors.lastname: Hara
authors.forename: Ken
authors.initials: K
authors.lastname: Kubota
authors.forename: Terumi
authors.initials: T
authors.lastname: Kamisawa
mesh_terms: D000017:ABO Blood-Group System; D000368:Aged; D016009:Chi-Square Distribution; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications*; D005260:Female; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010190:Pancreatic Neoplasms / Q000097:blood / Q000209:etiology*; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012698:Serologic Tests; D013997:Time Factors
chemical_list: D000017:ABO Blood-Group System
keywords: ABO blood type; Diabetes mellitus; Pancreatic cancer; Risk factor; Screening