Pancreatic cancer is the growth of cancer cells in the pancreas. The pancreas is a long, flattened pear-shaped organ in the abdomen. It makes exocrine and endocrine enzymes and hormones including insulin and glucogon.

It makes and releases enzymes that help the body absorb foods, especially fats. These hormones help your body control blood sugar levels. Cancer occurs when cells in the body divide without control or order. If cells keep dividing uncontrollably, a mass of tissue forms. This is called a growth or tumor. The term cancer refers to malignant tumors. They can invade nearby tissue and spread to other parts of the body.

Etiology

The exact etiology of pancreatic cancer is unknown. There is a small genetic correlation with family history.  A role for familial aggregation and/or genetic factors is suggested by the fact that 5 to 10 percent of patients with exocrine pancreatic cancer have a first degree relative with the disease. Only about 3 of every 100 patients with pancreatic cancer have the “familial form.” In the United States, approximately 43,140 patients are diagnosed with cancer of the exocrine pancreas annually, and unfortunately almost all are expected to die from the disease.  Pancreatic cancer is the fourth leading cause of cancer-related death in the United States among both men and women. The majority of these tumors (85 percent) are adenocarcinomas arising from the ductal epithelium.

The disease is rare before the age of 45, but the incidence rises sharply thereafter. The incidence is greater in males than females (male-to-female ratio 1.3:1) and in blacks (14.8 per 100,000 in black males compared to 8.8 per 100,000 in the general population).

Risk Factors

Pancreatic cancer is more common in smokers and people who are obese. The risk increases with age. Other risk factors include: Diabetes, chronic pancreatitis, hereditary pancreatitis, family nonpolyposis colon cancer syndrome, family or personal history of certain types of colon polyps or colon cancer, family history of pancreatic cancer (especially in Ashkenazi Jews with BRCA2 – breast cancer associated) gene, and high fat diet. A two- to fivefold increased risk of developing pancreatic cancer 15 to 20 years after partial gastrectomy has been described. An increased incidence has also been observed in patients who underwent cholecystectomy.

Symptoms

In a majority of cases, at the time of diagnosing pancreatic cancer, the patient presents with advanced stages. Pancreatic cancer does not cause symptoms in its early stages. The cancer may grow for some time before it causes symptoms. When symptoms do appear, they may be very vague. In many cases, the cancer has spread outside the pancreas by the time it is discovered.

Symptoms include:

• Nausea
• Loss of appetite
• Unexplained weight loss
• Pain—in the upper abdomen, sometimes spreading to the back (a result of the cancer growing and spreading)
• Jaundice —yellowness of skin and whites of the eyes; dark urine (if the tumor blocks the common bile duct); tan stool or stool that floats to the top of the bowl.
• Weakness, dizziness, chills, muscle spasms, diarrhea (especially if the cancer involves the islet cells that make insulin and other hormones)
  • Back pain
  • Blood clots due to hypercoagulable states
  • Depression
  • Diarrhea
  • Indigestion

Diagnosis

Initial laboratory evaluation includes complete blood count, complete metabolic panel, PT/INR. Routine laboratory tests may reveal a rise in the serum bilirubin concentration and alkaline phosphatase activity, and the presence of mild anemia. Several serum markers for pancreatic cancer have been evaluated, the most useful of which is cancer associated antigen 19-9 (CA 19-9).  The reported sensitivity and specificity for pancreatic cancer are 80 to 90 percent, respectively.

Radiologic Investigations

A variety of diagnostic studies are available for the diagnosis and staging of pancreatic cancer. The diagnosis of pancreatic cancer is typically made radiographically by the finding of a mass within the pancreas, which often obstructs the pancreatic duct or biliary tree. Contrast-enhanced multislice (multidetector) helical computed tomography (MDCT) scanning with three dimensional reconstruction is the preferred method to diagnose and stage pancreatic cancer. Other imaging studies that may be helpful in the diagnostic evaluation include transcutaneous or endoscopic ultrasound (US or EUS); endoscopic retrograde cholangiopancreatography (ERCP); magnetic resonance imaging (MRI), and MR cholangiopancreatography (MRCP). The utility of PET in the diagnostic and staging evaluation of suspected pancreatic cancer is uncertain.

Treatment

Because pancreatic cancer is often advanced when it is first found, very few pancreatic tumors can be removed by surgery. The standard procedure is called a pancreaticoduodenectomy (Whipple procedure). Removal of the cancerous tumor and nearby tissue may be done. Nearby lymph nodes may also need to be removed. In pancreatic cancer, surgery may also be performed to relieve symptoms. Surgeries include: Whipple procedure, total pancreatectomy and distal pancreatectomy.

Surgery should be done at centers that perform the procedure frequently. When the tumor has not spread out of the pancreas but cannot be removed, radiation therapy and chemotherapy together may be recommended.

When the tumor has metastasized to other organs such as the liver, chemotherapy alone is usually used. The standard chemotherapy drug is gemcitabine, but other drugs may be used. Gemcitabine can help approximately 25 percent of patients.

Patients whose tumor cannot be totally removed, but who have a blockage of the tubes that transport bile (biliary obstruction) must have that blockage relieved. There are generally two approaches to this: surgery or placement of a tiny metal tube (biliary stent) during ERCP.

Management of pain and other symptoms is an important part of treating advanced pancreatic cancer.

What is the Prognosis?

A minority of patients with pancreatic cancer who present at early stages can have surgical resection and can be curative. However, in more than 80 percent of patients the tumor has already spread and cannot be completely removed at the time of diagnosis.

Is screening for pancreatic cancer helpful?

Although imaging surveillance of high-risk family cohorts is pursued at some centers, it has not yet been shown to improve survival and this practice has been considered by some to be investigational.

Srinivas Seela, MD maintains a practice at The Digestive and Liver center of Florida.  He finished his fellowship in gastroenterology at Yale University School of Medicine. Dr. Seela is board certified in both Internal Medicine and Gastroenterology.  He is a member of American Society of Gastroenterology, American Gastroenterology Association, American Association of Liver Diseases and Crohn’s Colitis foundation. Any comment and suggestions can be e-mailed to sseela@dlcfl.com

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