What Is the #1 Cause of Pancreatic Cancer?

Pancreatic cancer causes are complex and may have a genetic component, but researchers agree that smoking and obesity are the top identifiable external causes for pancreatic cancer.

Pancreatic cancer occurs when cells in the pancreas grow out of control.

The most common type of pancreatic cancer is pancreatic adenocarcinoma, which accounts for about 95% of cases. Pancreatic neuroendocrine tumors (NETs), or islet cell tumors, are less common but tend to have a better prognosis.

Pancreatic cancer is thought to be caused by genetic mutations but the exact cause for these gene changes is unknown. 

Risk factors for developing pancreatic cancer include: 

• Tobacco use/smoking
  • One of the most common causes of pancreatic cancer 
  • About 25% of pancreatic cancers are thought to be caused by cigarette smoking
  • The risk of developing pancreatic cancer is two to three times higher than in non-smokers
• Age
  • Risk increases with age
  • About 90% of patients are over age 55
  • About two-thirds of patients are at least 65 years old
  • The average age at diagnosis is 70
• Being overweight or obese 
  • People with a body mass index (BMI) of 30 or more are about 20% more likely to develop pancreatic cancer
  • Gaining weight as an adult 
  • Carrying extra weight around the waistline even in people who are not overweight
  • Gender: men are slightly more likely to develop pancreatic cancer than women (this may be due to greater tobacco use in men)
• Race/ethnicity
  • African Americans are slightly more likely to develop pancreatic cancer than whites, Asians, or Hispanics
  • People of Ashkenazi Jewish heritage are more likely to develop pancreatic cancer
• Family history
• Poor diet
  • Regular consumption of fatty foods
• Chronic or heavy alcohol use
• Diabetes
• Chronic pancreatitis
• Chemical exposures
  • Workplace exposure to certain chemicals such as those used in the dry cleaning and metal working industries 
  • Pesticides, benzene, certain dyes, and petrochemicals 
• Inherited genetic syndromes 
  • Hereditary pancreatitis
  • Peutz-Jeghers syndrome 
  • Familial malignant melanoma and pancreatic cancer 
  • Hereditary breast and ovarian cancer (HBOC) syndrome
  • Lynch syndrome
  • Li-Fraumeni syndrome 
  • Familial adenomatous polyposis 
• Helicobacter pylori (H. pylori) infection
• Cirrhosis
• Hepatitis B infection (more research is needed on this possible connection)