Most of the time, “pancreatic cancer” means pancreatic ductal adenocarcinoma — cancer that begins in the small tubes (ducts) inside the pancreas. A different type of cancer called a neuroendocrine tumor (NET) can also affect the pancreas.
Seattle Cancer Care Alliance (SCCA) offers comprehensive treatment for pancreatic cancer and pancreatic NETs from a team of experts who specialize in gastrointestinal cancers.
What is pancreatic cancer?
When cells begin to grow abnormally they can turn into cancer. Cancer cells do not respond to regular cell growth, division and death signals like they are supposed to. They also don’t organize normally. Instead they grow into a tumor, which may break through nearby tissues or spread to other parts of the body.
Understanding your pancreas
Your pancreas is in your abdomen, behind your stomach. It is surrounded by your small intestine, liver and spleen.
Most of your pancreas consists of exocrine cells. These cells produce and secrete enzymes that aid in the breakdown of foods.
- Lipase breaks down fats.
- Protease breaks down proteins.
- Amylase breaks down carbohydrates.
A small portion of your pancreas consists of endocrine cells. These cells produce and secrete hormones, including:
- Gastrin, which triggers release of acid in your stomach
- Insulin, which helps lower the level of sugar in your blood
Types of cancer in the pancreas
It is important to know whether a pancreatic tumor started in the exocrine cells or endocrine cells because there are different treatment strategies and prognoses for each type of tumor.
The term “pancreatic cancer” is often used to refer to cancer that started in the exocrine cells of the pancreas.
Most pancreatic cancers are exocrine cancers that begin in the ducts that carry pancreas juices and enzymes to the common bile duct, which empties into the first section of the small intestine (duodenum). The most common is pancreatic ductal adenocarcinoma.
Pancreatic cancer is often diagnosed at later stages, when the cancer has grown around major blood vessels or spread to other organs. Even then, there is a lot we can do to help control your symptoms and extend your life.
Tumors that start in the endocrine cells of the pancreas are called pancreatic NETs. They are also known as neuroendocrine tumors of the pancreas or islet cell tumors, and they are different from pancreatic ductal adenocarcinoma.
NETs can be either malignant (cancer) or benign (not cancer).
Malignant pancreatic NETs are very rare, accounting for about 1 percent of newly diagnosed cancers in the pancreas. Some secrete hormones (functional NETs), and others don’t (nonfunctional NETs).
There are several types of NETs, named for the type of endocrine cell where they began. The most common functional NETs are:
- Gastrinoma, which makes large amounts of the hormone gastrin
- Insulinoma, which makes too much of the hormone insulin
Pancreatic NETs can often be cured. Your treatment and prognosis depend on several factors, such as where the NETs are in your pancreas, whether the cancer has spread elsewhere and how healthy you are overall.
Learn more about pancreatic NETs symptoms and diagnosis here.
Most cancers in the pancreas, including nonfunctional pancreatic NETs, do not cause symptoms until they become large or spread to other parts of the body.
Exocrine pancreatic cancer is often advanced by the time it is found.
- One of the most pronounced symptoms is pain in the upper abdomen and back.
- At times the cancer may cause the gallbladder to swell.
- Because 80 percent of pancreatic cancers occur in the head of the pancreas, where they can block the bile duct, they may cause jaundice (yellowing of the skin or whites of the eyes and darkened urine).
- When cancer interferes with food processing, it can cause weight loss, pale and greasy stools, and vomiting and nausea after eating.
If you have signs or symptoms that could be from cancer in your pancreas, your doctor will start by asking about your medical history and family history and doing a physical exam.
If your doctor suspects you have exocrine pancreatic cancer, you may have one or more imaging studies, such as:
- Computed tomography (CT) scan — to look for any abnormal growth on your pancreas and cancer anywhere else in your body.
- Upper endoscopic ultrasound (upper EUS) — threading a flexible tube (endoscope) with an ultrasound probe through your mouth into your stomach to look at your tumor, determine whether it can be removed surgically and take cells for a biopsy (looking at them under a microscope to see if they are cancer).
- Magnetic resonance imaging (MRI) — to get a picture of your pancreas ducts if your major blood vessels are compressed or invaded by cancer and to look at your liver for signs that cancer has spread there.
- Endoscopic retrograde cholangiopancreatography (ERCP) — threading an endoscope through your mouth into your small intestine to look at your pancreas, inject dye that helps the area show up better on an X-ray or use a fine needle or brush to take cells for a biopsy. ERCP can also be used to place a stent to help relieve jaundice.
Traditionally, patients with pancreatic cancer have needed exploratory surgery to determine whether their pancreas should be removed. Now doctors often opt for the less invasive imaging procedures described above.
Tests for CA 19-9, a molecule released into the blood by some pancreatic tumor cells, can be useful in tracking the progression of the disease, but it is only 80 percent accurate in diagnosing pancreatic cancer.
What causes pancreatic cancer?
Very little is known about the exact cause of pancreatic cancer. Many studies have drawn links between the disease and various types of behaviors and genetic groups.
SCCA’s Gastrointestinal Cancer Prevention Program offers a personalized approach to risk assessment, screening and prevention for people at high risk for pancreatic cancer and other gastrointestinal cancers.
These factors may affect your risk for pancreatic cancer:
- Smoking — Adenocarcinomas are two to three times more common in heavy smokers than in nonsmokers.
- Age — Though pancreatic cancers are sometimes found in young people, most are found in people over 60.
- Sex — Men are more often diagnosed than women.
- Ethnicity —African-Americans, Ashkenazi Jews and Native Hawaiians have the highest rates of pancreatic cancer. Asians and Hispanics have the lowest rates.
- Diet — A diet high in meats and fats has been linked to increased risk.
- Environment — Pancreatic cancer is more common in people with prolonged exposure to pesticides, dyes, petrochemicals and other carcinogens.
- Family history — People with a parent or sibling who has had pancreatic cancer are three times more likely to also be diagnosed. A family history of colon cancer or ovarian cancer also increases the risk of pancreatic cancer.
How common is pancreatic cancer?
The American Cancer Society estimates that about 55,000 people in the United States will be diagnosed with pancreatic cancer (either exocrine or endocrine) each year.