title: The Relationship between Metformin and Cancer in Patients with Type 2 Diabetes.
abstract: BACKGROUND
  Recently, several studies reported that the cancer incidence in type 2 diabetes patients is higher than in the general population. Although a number of risks are shared between cancer and diabetes patients, there have been few studies of its correlation. We evaluated the influences of several factors including low density lipoprotein cholesterol (LDL-C), albuminuria and use of metformin on the risk of cancer in patients with type 2 diabetes.
  
  
  METHODS
  We enrolled 1,320 patients with at least 5 years of follow-up and 73 patients were diagnosed with cancer during this period. The associations of the risk factors with cancer incidence were evaluated by multiple regression analysis. The subjects were placed into two subgroups based on metformin dosage (<1,000 mg/day, ≥1,000 mg/day) and we compared cancer incidence using analysis of covariance.
  
  
  RESULTS
  LDL-C and albuminuria were not significantly correlated with cancer risk. In contrast, metformin showed a reverse correlation with cancer risk (P=0.006; relative risk, 0.574). In the metformin nonadministration group, smoking, male gender, and high triglyceride levels tended to be contributing factors without statistical significance. Cancer occurence was lower in the low dose metformin group (less than 1,000 mg/day) (P=0.00).
  
  
  CONCLUSIONS
  These results suggest that the administration of low dose metformin in patients with type 2 diabetes may be associated with a reduced risk of cancer.
authors: Department of Internal Medicine, Yeungnam University College of Medicine, Daegu, Korea.
authors: Hyun Hee
authors: HH
authors: Chung
authors: Jun Sung
authors: JS
authors: Moon
authors: Ji Sung
authors: JS
authors: Yoon
authors: Hyoung Woo
authors: HW
authors: Lee
authors: Kyu Chang
authors: KC
authors: Won
keywords: Diabetes mellitus, type 2; Metformin; Neoplasms
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