Diabetes and pancreatic cancer: chicken or egg?

Pancreas. 2011 Apr;40(3):339-51. doi: 10.1097/MPA.0b013e318209e05d.


Objectives: Although half of all patients with pancreatic cancer are diabetic at the time of diagnosis, it remains unclear whether the diabetes associated with pancreatic cancer is a cause or an effect of the malignancy.

Methods: Epidemiologic studies were reviewed, the geographic prevalence of diabetes and the incidence of pancreatic cancer were examined, and clinical and laboratory studies were reviewed.

Results: Long-standing diabetes increases the risk of pancreatic cancer by 40% to 100%, and recent-onset diabetes is associated with a 4- to 7-fold increase in risk, such that 1% to 2% of patients with recent-onset diabetes will develop pancreatic cancer within 3 years. Treatment of diabetes or morbid obesity decreases the risk of pancreatic cancer, and metformin therapy decreases the risk due to both its antidiabetic and antineoplastic effects. Recent-onset diabetes associated with pancreatic cancer likely represents secondary or type 3 diabetes. The discrimination of type 3 diabetes from the more prevalent type 2 diabetes may identify the high-risk subgroup of diabetic patients in whom potentially curable pancreatic cancer may be found.

Conclusions: Type 2 and type 1 diabetes mellitus increase the risk of pancreatic cancer with a latency period of more than 5 years. Type 3 diabetes mellitus is an effect, and therefore a harbinger, of pancreatic cancer in at least 30% of patients.

Publication types

  • Review

MeSH terms

  • Biomarkers, Tumor / blood
  • Case-Control Studies
  • Causality
  • Diabetes Complications / epidemiology
  • Diabetes Complications / etiology*
  • Diabetes Mellitus / therapy
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / drug therapy
  • Diabetes Mellitus, Type 2 / epidemiology
  • Diabetes Mellitus, Type 2 / etiology
  • Female
  • Glucose / metabolism
  • Humans
  • Islet Amyloid Polypeptide / blood
  • Male
  • Metformin / therapeutic use
  • Pancreatic Neoplasms / complications*
  • Pancreatic Neoplasms / epidemiology
  • Pancreatic Neoplasms / etiology*
  • Pancreatic Neoplasms / prevention & control
  • Risk Factors
  • United States / epidemiology


  • Biomarkers, Tumor
  • Islet Amyloid Polypeptide
  • Metformin
  • Glucose