Does Smoking Increase Pancreatic Cancer Risk?

Smoking is a major risk factor for pancreatic cancer. Quitting can help reduce the chance of developing it.

Smoking may also increase the risk of death in people with pancreatic cancer.

This article explains the link between smoking and pancreatic cancer.

How Much Does Smoking Increase Pancreatic Cancer Risk?

Compared with never smoking, smoking increases pancreatic cancer risk twofold.

Approximately 25% of pancreatic cancers are linked to smoking, making it a major risk factor.

Cigar smoking and smokeless tobacco are also associated with increased pancreatic cancer risk.

A 2020 review reported that tobacco smoking may increase the risk of pancreatic ductal adenocarcinoma (PDAC), the most common pancreatic cancer, by approximately 70%.

A 2020 study suggested that unfiltered cigarettes and childhood smoke exposure increase risk. Black tobacco was associated with greater pancreatic cancer risk than blond tobacco, although all types increased risk.

How Does Smoking Increase Pancreatic Cancer Risk?

A 2022 review states that tobacco contains more than 7000 chemicals, at least 60 of which are proven carcinogens. These chemicals can cause cellular changes contributing to cancer.

Exactly How Does Smoking Affect the Pancreas?

Although the precise mechanism is unknown, reviews suggest several possibilities:

• Cell Damage: Tobacco smoke may damage pancreatic cells that produce digestive juices, causing abnormal growth and tumor formation. This has been observed in smoke-exposed mice and people who smoke heavily.
• Reduced Insulin Production: Smoking may cause hormone-producing pancreatic islet cells to release less insulin, which regulates blood glucose. Cells also produce more glucagon, increasing glucose. These effects increase diabetes risk, another pancreatic cancer risk factor.
• Inflammation and Scarring: Smoking can cause pancreatic inflammation and scarring, creating conditions that make cancer cell growth and spread easier. Tobacco carcinogens can damage DNA and accelerate cell multiplication.

A 2017 review also describes damage to pancreatic exocrine tissue, which supplies digestive juices to the intestine. PDAC develops in this tissue and accounts for more than 90% of pancreatic cancers.

Does Smoking Increase the Risk of Death From Pancreatic Cancer?

Continuing to smoke after diagnosis may reduce survival chances.

In a 2017 study of 1,037 patients, researchers compared survival in smokers and nonsmokers. Heavy smokers had greater mortality risk than nonsmokers, whereas former smokers had risks similar to never-smokers.

A 2019 review of 20 studies involving more than 2.5 million pancreatic cancer patients found higher mortality in both current and former smokers than never-smokers.

Does Quitting Reduce Pancreatic Cancer Risk?

Quitting can help reduce risk.

A 2023 review found that with each year after quitting, pancreatic cancer risk declined by 9%.

People with a 30-pack-year smoking history who quit before age 50 had risk similar to never-smokers.

The authors cited earlier research suggesting that substantial risk reduction may take 20-30 years. However, some studies suggested that risk may return to never-smoker levels within 5-15 years.

What Are Other Pancreatic Cancer Risk Factors?

Smoking is important, but other risk factors also exist.

These include:

• Obesity
• Diabetes
• Chronic pancreatitis
• Exposure to certain chemicals in metalworking or dry-cleaning industries
• Age: this cancer is more common after 45
• A family history of pancreatic cancer
• Certain genetic conditions, including:
  • Hereditary breast cancer
  • Hereditary breast and ovarian cancer syndrome
  • Hereditary pancreatitis
  • Familial atypical multiple mole melanoma syndrome
  • Peutz-Jeghers syndrome
  • Lynch syndrome. Pancreatic cancer is slightly more common in men and African Americans.

Frequently Asked Questions About Pancreatic Cancer

What Is the Median Age at Death From Pancreatic Cancer?

According to the United States National Cancer Institute (US-NCI), the median age is 72. Approximately 31.2% of pancreatic cancer deaths occur between ages 65-74.

What Are the Chances of Successful Treatment?

The chances of a complete cure are lower than for many other cancers. The United States National Cancer Institute (US-NCI) estimates a 5-year relative survival rate of 44.3% for regional disease and 3.2% for stage 4 or distant disease.

New treatments such as mRNA vaccines may reduce mortality over time, but remain in clinical trials and may take several years to become widely available.

Relative survival offers an idea of how long someone with a condition may live after diagnosis compared with people without it.

For example, a 5-year relative survival rate of 70% means someone with the condition is 70% as likely to survive 5 years as someone without it.

These are estimates. A healthcare professional can help explain how the condition may affect an individual.

Summary

Smoking approximately doubles pancreatic cancer risk and is linked to around 25% of diagnoses.

Tobacco chemicals can cause cellular changes, damage pancreatic exocrine tissue and affect hormone production. These effects may also increase diabetes risk, which is linked to pancreatic cancer.

Quitting may help reduce risk to the level of someone who has never smoked, but this can take decades.

A doctor can advise on quitting smoking and other steps to reduce pancreatic cancer risk.