Types of Cancer : Pancreatic Cancer

Definition

Pancreatic cancer begins 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 sugars.

Pancreatic cancer often has a poor prognosis, even when diagnosed early. Pancreatic cancer typically spreads rapidly and is seldom detected in its early stages, which is a major reason why it's a leading cause of cancer death. Signs and symptoms may not appear until pancreatic cancer is quite advanced and surgical removal isn't possible.

Symptoms

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

• Upper abdominal pain that may radiate to your back
• Yellowing of your skin and the whites of your eyes (jaundice)
• Loss of appetite
• Weight loss
• Depression

Causes

Pancreatic cancer occurs when cells in your pancreas develop genetic mutations. These mutations cause the cells to grow uncontrollably and to continue living after normal cells would die. These accumulating cells can form a tumor.

Understanding your pancreas
Your pancreas is about 6 inches (15 centimeters) long and looks something like a pear lying on its side. The pancreas is a crucial part of your digestive system. It secretes hormones, including insulin, to help your body process sugar. And it produces digestive juices to help your body digest food.

Types of pancreatic cancer
The types of cells involved in a pancreatic cancer help determine the best treatment. Types of pancreatic cancer include:

• Cancer that forms in the pancreas ducts (adenocarcinoma). Cells that line the ducts of the pancreas help produce digestive juices. The majority of pancreatic cancers are adenocarcinomas. Sometimes these cancers are called exocrine tumors.
• Cancer that forms in the hormone-producing cells. Cancer that forms in the hormone-producing cells of the pancreas is called endocrine cancer. Endocrine cancers of the pancreas are very rare.

Risk factors

Factors that may increase your risk of pancreatic cancer include:

• Smoking.
• Being overweight or obese.
• Personal or family history of chronic inflammation of the pancreas (pancreatitis).
• Personal or family history of pancreatic cancer.
• Family history of genetic syndromes that can increase cancer risk, including a BRCA2 gene mutation, Peutz-Jeghers syndrome, Lynch syndrome and familial atypical mole-malignant melanoma (FAMMM).
• Older age. Pancreatic cancer occurs most often in older adults. Most people diagnosed with pancreatic cancer are in their 70s and 80s.
• Being black. Pancreatic cancer occurs more frequently in blacks than in whites.

When to seek medical advice

See your doctor if you experience an unexplained weight loss, abdominal pain, jaundice, or other signs and symptoms that bother you. Many diseases and conditions other than cancer may cause similar signs and symptoms, so your doctor will check for these conditions as well as for pancreatic cancer.

Tests and diagnosis

Researchers are studying ways to detect pancreatic cancer early. However, it isn't clear who should undergo screening and which screening tests may most reliably find pancreatic cancer in its earliest stages. Currently no standard screening exists for pancreatic cancer.

Diagnosing pancreatic cancer
If your doctor suspects pancreatic cancer, you may have one or more of the following tests to diagnose the cancer:

• Ultrasound. Ultrasound uses high-frequency sound waves to create moving images of your internal organs, including your pancreas. The ultrasound sensor (transducer) is placed on your upper abdomen to obtain images.
• Computerized tomography (CT) scan. CT scan uses X-ray images to help your doctor visualize your internal organs. In some cases you may receive an injection of dye into a vein in your arm to help highlight the areas your doctor wants to see.
• Magnetic resonance imaging (MRI). MRI uses a powerful magnetic field and radio waves to create images of your pancreas.
• Endoscopic retrograde cholangiopancreatography (ERCP). This procedure uses a dye to highlight the bile ducts in your pancreas. During ERCP, a thin, flexible tube (endoscope) is gently passed down your throat, through your stomach and into the upper part of your small intestine. Air is used to inflate your intestinal tract so that your doctor can more easily see the openings of your pancreatic and bile ducts. A dye is then injected into the ducts through a small hollow tube (catheter) that's passed through the endoscope. Finally, X-rays are taken of the ducts. A tissue or cell sample (biopsy) can be collected during ERCP.
• Endoscopic ultrasound (EUS). EUS uses an ultrasound device to make images of your pancreas from inside your abdomen. The ultrasound device is passed through an endoscope into your stomach in order to obtain the images. Your doctor may also collect a sample of cells (biopsy) during EUS.
• Percutaneous transhepatic cholangiography (PTC). PTC involves injecting a dye into your liver to highlight your bile ducts. Your doctor carefully inserts a thin needle into your liver and injects the dye into the bile ducts in your liver. A special X-ray machine (fluoroscope) tracks the dye as it moves through the ducts.
• Biopsy. During a biopsy, your doctor obtains a small sample of tissue from the pancreas for examination under a microscope. A biopsy sample can be obtained by inserting a needle through your skin and into your pancreas (fine-needle aspiration). Or it can be done using endoscopic ultrasound to guide special tools into your pancreas where a sample of cells can be obtained for testing.

Staging pancreatic cancer
Once a diagnosis of pancreatic cancer is confirmed, your doctor will work to determine the extent, or stage, of the cancer. Your cancer's stage helps determine what treatments are available to you. In order to determine the stage of your pancreatic cancer, your doctor may recommend:

• Laparoscopy. Laparoscopy uses a lighted tube with a video camera to explore your pancreas and surrounding tissue. The surgeon passes the laparoscope through an incision in your abdomen. The camera on the end of the scope transmits video to a screen in the operating room. This allows your doctor to look for signs cancer has spread within your abdomen.
• Chest X-ray. A chest X-ray helps your doctor look for signs that cancer has spread to your lungs.
• CT scan. CT scans allow your doctor to see your pancreas and assess whether the cancer has spread to nearby tissues, lymph nodes or other organs.
• MRI. MRI images may show if the cancer has spread beyond the pancreas.
• Positron emission tomography (PET) scan. PET scans use a radioactive tracer injected into a vein in order to help your doctor look for areas where cancer has spread beyond the pancreas. PET scans aren't typically used for pancreatic cancer, but they may offer another way to examine unusual areas found with a CT scan or MRI.
• Bone scan. Bone scans use radioactive tracers to look for evidence that cancer cells have spread to your bones.
• Blood test. Your doctor may test your blood for specific proteins (tumor markers) shed by pancreatic cancer cells. One tumor marker test used in pancreatic cancer is called CA19-9. Some research indicates that the more elevated your level of CA19-9 is, the more advanced the cancer. But the test isn't always reliable, and it isn't clear how best to use the CA19-9 test results. Some doctors measure your levels before, during and after treatment. Others use it to gauge your prognosis.

Stages of pancreatic cancer
The stages of pancreatic cancer can be expressed in different ways. One description of the stages uses three broad categories:

• Resectable. All the tumor nodules can be removed.
• Locally advanced. The tumor can no longer be removed with surgery because the cancer has spread to tissues around the pancreas or into the blood vessels.
• Metastatic. At this stage, the cancer has spread to distant organs, such as the lungs and liver.

Another description of the stages uses numerals:

• Stage I. Cancer is confined to the pancreas.
• Stage II. Cancer has spread beyond the pancreas to nearby tissues and organs and may have spread to the lymph nodes.
• Stage III. Cancer has spread beyond the pancreas to the major blood vessels around the pancreas and may have spread to the lymph nodes.
• Stage IV. Cancer has spread to distant sites beyond the pancreas, such as the liver, lungs and the lining that surrounds your abdominal organs (peritoneum).

Complications

As pancreatic cancer progresses, it can cause complications such as:

• Jaundice. Pancreatic cancer that blocks the liver's bile duct can cause jaundice. Signs include yellow skin and eyes, dark-colored urine and very pale stools.

  Your doctor may recommend that a plastic or metal tube (stent) be placed inside the bile duct to hold it open. In some cases a bypass may be needed to create a new way for bile to flow from the liver to the intestines.

• 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. Radiation therapy may help stop tumor growth temporarily to give you some relief.

  In severe cases, your doctor may 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 small intestine (duodenum) can block the flow of digested food from your stomach into your intestines.

  Your doctor may recommend a tube (stent) be placed in your small intestine to hold it open. Or bypass surgery may be necessary to attach your stomach to a lower point in your intestines that isn't blocked by cancer.

• Weight loss. A number of factors may cause weight loss in people with pancreatic cancer. 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 properly processing nutrients from food because your pancreas isn't making enough digestive juices.

  Your doctor will work to correct the factors contributing to your weight loss. Pancreatic enzyme supplements may be recommended to aid in digestion. Try to maintain your weight by adding extra calories where you can and making mealtime as pleasant and relaxed as possible.

• Death. Pancreatic cancer leads to death for most people diagnosed with the disease. Even people diagnosed when their cancer is at an early stage face a high risk of recurrence and death.

Treatments and drugs

Treatment for pancreatic cancer depends on the stage and location of the cancer as well as on your age, overall health and personal preferences. The first goal of pancreatic cancer treatment is to eliminate the cancer, when possible. When that isn't an option, the focus may be on preventing the pancreatic cancer from growing or causing more harm. When pancreatic cancer is advanced and treatments aren't likely to offer a benefit, your doctor may suggest ways to relieve symptoms and make you as comfortable as possible.

Surgery
Only a small portion of pancreatic cancers are considered resectable — that is, they have a good chance of being removed completely with surgery. Once the cancer has spread beyond the pancreas to other organs, lymph nodes or blood vessels, surgery is usually no longer an option. When surgery is possible, your surgeon may recommend:

• Surgery for tumors in the pancreatic head. If your pancreatic cancer is located in the head of the pancreas, you may consider an operation called a Whipple procedure (pancreatoduodenectomy). The Whipple procedure involves removing the head of your pancreas, as well as a portion of your small intestine (duodenum), your gallbladder and part of your bile duct. Part of your stomach may be removed as well. Your surgeon reconnects the remaining parts of your pancreas, stomach and intestines to allow you to digest food.

  Whipple surgery carries a risk of infection and bleeding. It can cause temporary diabetes until your pancreas recovers from surgery. And some people experience nausea and vomiting that can occur if the stomach has difficulty emptying after surgery (delayed gastric emptying). Expect a long recovery after a Whipple procedure. You'll spend 10 days or more in the hospital and then recover for several more weeks at home.

• Surgery for tumors in the pancreatic tail and body. Surgery to remove the tail of the pancreas or the tail and a small portion of the body is called distal pancreatectomy. Your surgeon may also remove your spleen. Surgery carries a risk of bleeding and infection.

Research shows pancreatic cancer surgery tends to cause fewer complications when done by experienced surgeons. Don't hesitate to ask about your surgeon's experience with pancreatic cancer surgery. If you have any doubts, get a second opinion.

Radiation therapy
Radiation therapy uses high-energy beams to destroy cancer cells. You may receive radiation treatments before or after cancer surgery, often in combination with chemotherapy. Or, your doctor may recommend a combination of radiation and chemotherapy treatments when your cancer can't be treated surgically.

Radiation therapy can come from a machine outside your body (external beam radiation), or it can be placed inside your body near your cancer (brachytherapy). Radiation therapy can also be used during surgery (intraoperative radiation).

Chemotherapy
Chemotherapy uses drugs to help kill cancer cells. Chemotherapy can be injected into a vein or taken orally. You may receive only one chemotherapy drug, or you may receive a combination of chemotherapy drugs.

Chemotherapy can also be combined with radiation therapy (chemoradiation). Chemoradiation is typically used to treat cancer that has spread beyond the pancreas, but only to nearby organs and not to distant regions of the body. This combination may also be used after surgery to reduce the risk that pancreatic cancer may recur.

In people with advanced pancreatic cancer, chemotherapy may be combined with targeted drug therapy.

Targeted drug therapy
Targeted drug therapy is an emerging area of cancer treatment. Targeted drugs attack specific abnormalities within cancer cells. The targeted drug erlotinib (Tarceva) blocks chemicals that signal cancer cells to grow and divide. Erlotinib is usually combined with chemotherapy for use in people with advanced pancreatic cancer.

Many other targeted drug treatments are under investigation in clinical trials. One such drug being studied is cetuximab (Erbitux), which targets the same signals as erlotinib but goes about it a different way.

Clinical trials
Clinical trials are studies to test new forms of treatment, such as new drugs, new approaches to surgery or radiation treatments, and novel methods such as gene therapy. If the treatment being studied proves to be safer or more effective than are current treatments, it will become the new standard of care.

Clinical trials can't guarantee a cure, and they may have serious or unexpected side effects. On the other hand, cancer clinical trials are closely monitored by the federal government to ensure they're conducted as safely as possible. And they offer access to treatments that wouldn't otherwise be available to you.

Talk to your doctor about what clinical trials are available and whether these may be appropriate for you.

New treatments currently under investigation in clinical trials include:

• Drugs that stop cancer from growing new blood vessels. Drugs called angiogenesis inhibitors may help stop cancer from using new blood vessels to get the nutrients it needs to grow. Blood vessels also give cancer cells a pathway to spread to other parts of the body.
• Pancreatic cancer vaccines. Cancer vaccines are being studied to treat cancer, rather than prevent disease, as vaccines are traditionally used. Cancer treatment vaccines use various strategies to enhance the immune system to help it recognize cancer cells as intruders. In one example, a vaccine may help train the immune system to attack a certain protein secreted by pancreatic cancer cells.

Prevention

Although there's no proven way to prevent pancreatic cancer, you can take steps to reduce your risk, including:

• Quit smoking. If you smoke, quit. Talk to your doctor about ways to help you quit, including support groups, medications and nicotine replacement therapy. If you don't smoke, don't start.
• Maintain a healthy weight. Being overweight increases your risk of pancreatic cancer. If you need to lose weight, aim for a slow, steady weight loss — 1 or 2 pounds (0.5 or 1 kilogram) a week. Combine daily exercise with a plant-focused diet with smaller portions to help you lose weight.
• Exercise regularly. 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 full of colorful fruits and vegetables and whole grains is good for you, and may help reduce your risk of cancer.