Pancreatic cancer begins in the tissues of your pancreas — an organ in your abdomen that lies behind the lower part of your stomach. Your pancreas releases enzymes that aid digestion and produces hormones that help manage your blood sugar.
Several types of growths can occur in the pancreas, including cancerous and noncancerous tumors. The most common type of cancer that forms in the pancreas begins in the cells that line the ducts that carry digestive enzymes out of the pancreas (pancreatic ductal adenocarcinoma).
Pancreatic cancer is seldom detected at its early stages when it's most curable. This is because it often doesn't cause symptoms until after it has spread to other organs.
Pancreatic cancer treatment options are chosen based on the extent of the cancer. Options may include surgery, chemotherapy, radiation therapy or a combination of these.
Signs and symptoms of pancreatic cancer often don't occur until the disease is advanced. They may include:
- Abdominal pain that radiates to your back
- Loss of appetite or unintended weight loss
- Yellowing of your skin and the whites of your eyes (jaundice)
- Light-colored stools
- Dark-colored urine
- Itchy skin
- New diagnosis of diabetes or existing diabetes that's becoming more difficult to control
- Blood clots
When to see a doctor
See your doctor if you experience any unexplained symptoms that worry you. Many other conditions can cause these symptoms, so your doctor may check for these conditions as well as for pancreatic cancer.
It's not clear what causes pancreatic cancer. Doctors have identified some factors that may increase the risk of this type of cancer, including smoking and having certain inherited gene mutations.
Understanding your pancreas
Your pancreas is about 6 inches (15 centimeters) long and looks something like a pear lying on its side. It releases (secretes) hormones, including insulin, to help your body process sugar in the foods you eat. And it produces digestive juices to help your body digest food and absorb nutrients.
How pancreatic cancer forms
Pancreatic cancer occurs when cells in your pancreas develop changes (mutations) in their DNA. A cell's DNA contains the instructions that tell a cell what to do. These mutations tell the cells to grow uncontrollably and to continue living after normal cells would die. These accumulating cells can form a tumor. When left untreated, the pancreatic cancer cells can spread to nearby organs and blood vessels and to distant parts of the body.
Most pancreatic cancer begins in the cells that line the ducts of the pancreas. This type of cancer is called pancreatic adenocarcinoma or pancreatic exocrine cancer. Less frequently, cancer can form in the hormone-producing cells or the neuroendocrine cells of the pancreas. These types of cancer are called pancreatic neuroendocrine tumors, islet cell tumors or pancreatic endocrine cancer.
Factors that may increase your risk of pancreatic cancer include:
- Chronic inflammation of the pancreas (pancreatitis)
- Family history of genetic syndromes that can increase cancer risk, including a BRCA2 gene mutation, Lynch syndrome and familial atypical mole-malignant melanoma (FAMMM) syndrome
- Family history of pancreatic cancer
- Older age, as most people are diagnosed after age 65
A large study demonstrated that the combination of smoking, long-standing diabetes and a poor diet increases the risk of pancreatic cancer beyond the risk of any one of these factors alone.
As pancreatic cancer progresses, it can cause complications such as:
- Weight loss. A number of factors may cause weight loss in people with pancreatic cancer. Weight loss might happen as the cancer consumes the body's energy. Nausea and vomiting caused by cancer treatments or a tumor pressing on your stomach may make it difficult to eat. Or your body may have difficulty processing nutrients from food because your pancreas isn't making enough digestive juices.
Jaundice. Pancreatic cancer that blocks the liver's bile duct can cause jaundice. Signs include yellow skin and eyes, dark-colored urine, and pale-colored stools. Jaundice usually occurs without abdominal pain.
Your doctor may recommend that a plastic or metal tube (stent) be placed inside the bile duct to hold it open. This is done with the help of a procedure called endoscopic retrograde cholangiopancreatography (ERCP). During ERCP an endoscope is passed down your throat, through your stomach and into the upper part of your small intestine. A dye is then injected into the pancreatic and bile ducts through a small hollow tube (catheter) that's passed through the endoscope. Finally, images are taken of the ducts.
Pain. A growing tumor may press on nerves in your abdomen, causing pain that can become severe. Pain medications can help you feel more comfortable. Treatments, such as radiation and chemotherapy, might help slow tumor growth and provide some pain relief.
In severe cases, your doctor might recommend a procedure to inject alcohol into the nerves that control pain in your abdomen (celiac plexus block). This procedure stops the nerves from sending pain signals to your brain.
Bowel obstruction. Pancreatic cancer that grows into or presses on the first part of the small intestine (duodenum) can block the flow of digested food from your stomach into your intestines.
Your doctor may recommend that a tube (stent) be placed in your small intestine to hold it open. In some situations, it might help to have surgery to place a temporary feeding tube or to attach your stomach to a lower point in your intestines that isn't blocked by cancer.
You may reduce your risk of pancreatic cancer if you:
- Stop smoking. If you smoke, try to stop. Talk to your doctor about strategies to help you stop, including support groups, medications and nicotine replacement therapy. If you don't smoke, don't start.
- Maintain a healthy weight. If you are at a healthy weight, work to maintain it. If you need to lose weight, aim for a slow, steady weight loss — 1 to 2 pounds (0.5 to 1 kilogram) a week. Combine daily exercise with a diet rich in vegetables, fruit and whole grains with smaller portions to help you lose weight.
- Choose a healthy diet. A diet full of colorful fruits and vegetables and whole grains may help reduce your risk of cancer.
Consider meeting with a genetic counselor if you have a family history of pancreatic cancer. He or she can review your family health history with you and determine whether you might benefit from a genetic test to understand your risk of pancreatic cancer or other cancers.