Pancreatic Cancer

Pancreatic cancer is one of the most serious of all cancers. It develops when malignant cells form in the tissues of your pancreas — a large organ that lies horizontally behind the lower part of your stomach. Your pancreas secretes enzymes that aid digestion and hormones that help regulate the metabolism of carbohydrates.

Although pancreatic cancer accounts for just 2 percent of new cancer cases in the United States, it's the fourth leading cause of all cancer deaths. That's because pancreatic cancer spreads rapidly and is seldom detected in its early stages. Symptoms such as yellowing of the skin and whites of the eyes (jaundice), abdominal pain and unexplained weight loss may not appear until the disease is quite advanced. By that time, the cancer is likely to have spread (metastasized) to other parts of the body and surgical removal is no longer possible.

For years, little was known about pancreatic cancer. But researchers are beginning to understand the genetic basis of the disease — knowledge that may lead to new and better treatments. Just as important, you may be able to reduce your risk of pancreatic cancer with a few simple lifestyle changes.

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Signs and symptoms of pancreatic cancer often don't occur until the disease is advanced. When symptoms do appear, they may include:

• Upper abdominal pain that may radiate to your middle or upper back. About three-fourths of people with advanced pancreatic cancer experience abdominal pain when a tumor presses on surrounding organs and nerves. Pain may be constant or intermittent and is often worse after eating or when lying down. Because many conditions other than cancer can cause abdominal pain, it's important to discuss your symptoms carefully with your doctor.
• Loss of appetite and significant weight loss. Unintended weight loss is common in pancreatic cancer. Weight loss occurs in most types of cancer because malignant cells deprive healthy cells of nutrients. But the problem is compounded in pancreatic cancer, which often affects your ability to digest and absorb what you eat.
• Yellowing of your skin and the whites of your eyes (jaundice). Half of all people with pancreatic cancer develop jaundice, which occurs when bilirubin, a breakdown product of worn-out blood cells, accumulates in your blood. Normally, bilirubin is eliminated in bile, a fluid produced in your liver. But if a pancreatic tumor blocks the flow of bile, excess pigment from bilirubin may turn your skin and the whites of your eyes yellow. In addition, your urine may be dark brown and your stools white or clay-colored. Although jaundice is a common sign of pancreatic cancer, it's more likely to result from other conditions, such as gallstones or hepatitis.
• Itching. In the later stages of pancreatic cancer, you may develop severe itching when high levels of bile acids, another component of bile, accumulate in your skin.
• Nausea and vomiting. In advanced cases of pancreatic cancer, the tumor may block a portion of your digestive tract, usually the upper portion of your small intestine (duodenum), causing nausea and vomiting.
• Digestive problems. When cancer prevents pancreatic enzymes from being released into your intestine, you're likely to have a hard time digesting foods — especially those high in fat. Eventually, this may lead to weight loss — as much as 25 pounds or more — and malnutrition.
• Depression. Although most depression is not the result of pancreatic cancer, severe depression sometimes may be the first symptom of this disease.

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Your pancreas is about 6 inches long and looks something like a pear lying on its side. The wider end (head) is located near the center of your abdomen next to the upper part of your small intestine (duodenum). The main part (body) of the pancreas stretches behind your stomach, and the narrow end (tail) is on your left side, next to your spleen.

A part of your digestive system, your pancreas performs two essential functions. It produces digestive juices and enzymes that help break down proteins, carbohydrates and fats so the food you eat can be digested in your small intestine. It also secretes the hormones insulin and glucagon that regulate the way your body metabolizes sugar (glucose).

In order to carry out these different functions, your pancreas needs both exocrine and endocrine tissue. Endocrine glands, such as your pituitary and adrenals, secrete hormones directly into your bloodstream. Exocrine glands release substances into ducts or tubes that empty into your small intestine.

Most of your pancreas is composed of exocrine cells that produce digestive enzymes and juices. These cells are arranged in clusters and connected to a series of small ducts. Pancreatic juices flow from the cells through the ducts into the main pancreatic duct, which leads to your duodenum. The last portion of the bile duct, which carries bile from your liver and gallbladder, joins with the pancreatic duct just before it empties into your small intestine.

Your pancreas also contains small "islands" of endocrine cells located within the exocrine tissue. These cells, called the islets of Langerhans, secrete insulin and glucagon, along with somatostatin, which helps control the function of the other endocrine hormones.

Types of pancreatic cancer

Most pancreatic tumors originate in the exocrine duct cells or in the cells that produce digestive enzymes (acinar cells). Called adenocarcinomas, these tumors account for nearly 95 percent of pancreatic cancers.

Tumors that begin in the islet cells (endocrine tumors) are much less common. When they do occur, they may cause the affected cells to produce too much hormone. For example, tumors in glucagon cells (glucagonomas) might cause excess amounts of glucagon to be secreted, while tumors in insulin cells (insulinomas) may lead to an overproduction of insulin.

Tumors can also develop in the ampulla of Vater — the place where your bile and pancreatic ducts empty into your small intestine. Called ampullary cancers, these tumors often block the bile duct, leading to jaundice. Because even a small tumor can obstruct the bile duct, symptoms of ampullary cancer usually appear earlier than do symptoms of other pancreatic cancers.

Why pancreatic cancer occurs

Healthy cells grow and divide in an orderly way. This process is controlled by DNA — the genetic material that contains the instructions for every chemical process in your body. When DNA is damaged, changes occur in these instructions. One result is that cells may begin to grow out of control and eventually form a tumor — a mass of malignant cells.

Researchers don't know exactly what damages DNA in the vast majority of cases of pancreatic cancer. But it is known that a small percentage of people develop the disease as a result of a genetic predisposition. That is, people who have a close relative, such as a parent or sibling, with pancreatic cancer have a higher risk of developing pancreatic cancer themselves.

In addition, a number of genetic diseases have been associated with an increased risk of pancreatic cancer, including familial adenomatous polyposis, nonpolyposis colon cancer, familial breast cancer associated with the BRCA2 gene, hereditary pancreatitis, and familial atypical multiple mole-melanoma syndrome — a serious type of skin cancer. This means that people who have a hereditary predisposition to develop these cancers are also more likely to develop pancreatic cancer.

Yet less than 10 percent of pancreatic cancers result from an inherited tendency. A greater number are caused by environmental or lifestyle factors, including:

• Smoking. This is probably the greatest known cause of pancreatic cancer.
• Diet. A diet high in animal fat and low in fruits and vegetables may increase your risk of pancreatic cancer.
• Chemical exposure. People who work with petroleum compounds, including gasoline and other chemicals, have a higher incidence of pancreatic cancer than people not exposed to these chemicals.
• Obesity and physical inactivity. Excess weight and a sedentary lifestyle may increase your risk of pancreatic cancer.

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The vast majority of pancreatic cancers occur in people older than 60. Other important risk factors include:

• Race. Black men and women have a higher risk of pancreatic cancer than do whites or Asians.
• Sex. More men than women develop pancreatic cancer.
• Cigarette smoking. If you smoke, you're two to three times more likely to develop pancreatic cancer than nonsmokers are.
• Abnormal glucose metabolism. Having diabetes may increase your risk of pancreatic cancer. Diabetes that's diagnosed after age 50 may be an early warning sign of pancreatic cancer in some people.
• Hereditary pancreatitis. Your chances of developing pancreatic cancer increase if you have hereditary chronic pancreatitis. Hereditary pancreatitis (HP) is a rare genetic condition marked by recurrent attacks of pancreatitis — a painful inflammation of your pancreas.
• Excess weight. According to some studies, people who are very overweight or obese may have a greater risk of developing pancreatic cancer than do people of normal weight.
• Sedentary lifestyle. If you tend to be sedentary, you may be twice as likely to develop pancreatic cancer as someone who's active. But even moderate exercise may cut your risk, even if you're overweight.
• Ulcer surgery. Some studies have shown an increased risk of pancreatic cancer among people who have undergone surgery for peptic ulcers — sores in the lining of the stomach or small intestine. The longer the amount of time that passes after the surgery, the higher the risk.

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Although it's not always possible to prevent pancreatic cancer, these lifestyle changes may help reduce your risk:

• Quit smoking. The single most important thing you can do to prevent pancreatic cancer is to stop smoking. Cigarette smoke contains carcinogens that can damage the DNA that regulates cell growth. Talk to your doctor about the best ways to quit, or contact the American Cancer Society for more information.
• Maintain a healthy weight. Being overweight increases your risk of pancreatic cancer. If you need to lose weight, keep in mind that a slow, steady loss is the healthiest way to reach your goals. Aim for no more than 1 to 2 pounds a week. Add 30 minutes of aerobic exercise — such as walking, jogging or biking — on most days, and you can double the amount of weight you lose.
• Exercise regularly. Experts believe that getting even a moderate amount of exercise every week can cut your risk of pancreatic cancer. For overall health, aim for 30 minutes of exercise on most days. If you're not used to exercising, start out slowly and work up to your goal.
• Eat a healthy diet. A diet high in fruits and vegetables and low in animal fat can reduce your risk of pancreatic cancer. The American Cancer Society recommends eating at least five servings of fruits and vegetables every day, along with six servings of foods from other plant sources such asbreads, cereals, rice and beans. In addition, try to limit fats to no more than 30 percent of your total calories. Only 10 percent of your calories should come from saturated fats.

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Treatment for pancreatic cancer depends on the stage and location of the cancer as well as on your age, overall health and personal preferences. Especially when cancer is advanced, choosing a treatment plan is a major decision, and it's important to take time to evaluate your choices.

You may also want to consider seeking a second opinion. This can provide additional information to help you feel more certain about the option you're considering.

The goal of treatment is always to eliminate the cancer completely. When that isn't possible, the focus may be on preventing the tumor from growing or causing more harm. In some cases, an approach called palliative care may be best. Palliative care refers to treatment aimed not at removing or slowing the disease, but at helping relieve symptoms and making you as comfortable as possible.

Treatment for Pancreatic Cancer include:

• Surgery
• Radiation Therapy
• Chemotherapy
• Clinical Trials

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Only about 24% of patients with cancer of the exocrine pancreas do not die of the disease within 1 year of diagnosis, and only about 4% have not died from the cancer 5 years after diagnosis. Even for those people diagnosed with local disease (has not spread to other organs), the 5-year relative survival rate is only 17%.

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* Text Resources: The Mayo Clinic Staff