Pancreas Carcinoma

Pancreas Carcinoma

The pancreas is a long, flat organ located in the upper abdomen behind the stomach and adjacent to the duodenum. The pancreas is a complex gland performing both endocrine and exocrine functions. The exocrine glands secrete enzymes (pancreatic juice) that reaches the duodenum to help in the digestion of food. The endocrine glands secrete hormones, which are released into the blood. The most common type of pancreatic cancer is adenocarcinoma, or cancer of the gland-forming cells in the pancreas

Epidemiology

The incidence of pancreatic cancer increases with age with about two-thirds (63%) of reported cases diagnosed in patients over 70 years of age. Pancreatic cancer is the fourth leading cause of cancer deaths among men and women, accounting for 6% to 7% of all cancer-related deaths. Although, pancreatic cancer is not very common it is very deadly. It is the fourth highest cause of cancer-related deaths. Ductal adenocarcinomas are the most common form of pancreatic cancer.

Types of Pancreatic cancer

Adenocarcinoma of the ductal epithelium (80 % of all pancreatic cancers): Cancer originates in a cell of the duct of pancreas.

Other types of pancreatic cancer:

  • Insulinomas: Arise in the β-cells of pancreas, which produce insulin and leads to overproduction of insulin.
  • Glucagonomas: Arise in the α-cells of pancreas, which produce glucagon and leads to overproduction of glucagon.

 

Symptoms of ductal adenocarcinoma: The tumor blocks the duct. This stops the flow of bile into the duodenum which leads to the following consequences:

  • Abdominal pain: Pain starts in the upper abdomen or belly and may spread to the back.
  • Unintended Weight Loss: Generally unwell feeling and loss of weight.
  • Nausea: Nausea (vomiting), problems of indigestion and weakness.
  • Changes in urine and stool: Dark urine and pale feces.
  • Unexpected diabetes: Rarely, diabetes develops if nearly all the pancreas is damaged by the tumor.
  • Acute pancreatitis: Rarely, a tumor can elicit inflammation of the pancreas, called acute pancreatitis. This is accompanied by severe abdominal pain.
  • Yellowing of the Skin and Eyes: This is due to jaundice, which commonly occurs as the result of pancreatic cancer.

Risk factors

The exact cause of pancreas cancer could not be detected yet. Some risk factors have been identified. These are the following:

  • Age: People over 60 are very prone to developing pancreatic cancer.
  • Smoking and lifestyle: Long time smokers are at risk of developing this disease. A sedentary life style and obesity can also be other risk factors. Alcohol consumption may also be a risk factor.
  • Prolonged diabetes: History of diabetes increases the risk of developing this disease.
  • Chronic pancreatitis: Chronic inflammation of the pancreas increases the risk.
  • Hereditary conditions: Multiple endocrine neoplasia type 1 (MEN-1) syndrome, hereditary pancreatitis, von Hippel-Lindau syndrome, hereditary nonpolyposis colon cancer (HNPCC; Lynch syndrome), Peutz-Jeghers syndrome, familial atypical multiple mole melanoma syndrome (FAMMM) and ataxia-telangiectasia are some of the conditions that have been related to pancreatic cancer.
  • Pancreatic cysts: Certain types of pancreatic cysts may enhance the risk of developing pancreatic cancer.

Diagnosis

If jaundice is detected some initial tests will be done to detect whether it is due to a blockage from the head of the pancreas. If cancer is suspected from the symptoms of the patient and the initial assessments then the patients are recommended to undergo the following tests:

  • Abdominal CT scan (computerized tomography) and MRI scans: These can provide  images of pancreas, which can give a good idea of the condition of the pancreas.
  • Endoscopic ultrasound (EUS): This is a combined process of endoscopy and ultrasound scanning, which produces images of the digestive system and organs like pancreas associated with it. An endoscope (gastroscope) is a thin, flexible, telescope, which is inserted in the body through the mouth or rectum. It helps to visualize the organs while the ultrasound scanner produces images with the help of sound waves of high frequency.
  • Chest X-ray: It is performed to check whether or not the disease has spread.
  • Laparoscopy: This technique uses a laparoscope (tube like telescope with a light) to show the inside of abdomen. It is inserted through a small incision in the skin.
  • Biopsy: This is performed after a tumor has been detected. This can be of two types:
  • Percutaneous biopsy: A needle is inserted through the skin into the body with the help of an ultrasound or CT scanner to perform this biopsy.
  • Endoscopic biopsy: An endoscope is inserted through the mouth to reach the duodenum and then with the help of an ultrasound scanner a needle biopsy can be performed. Heavy sedation is required before employing this on the patient.
  • Routine blood studies: CA 19-9 test is done in blood samples. It is a protein secreted by the cancerous pancreas in the blood. Its levels are elevated in 80 % cancer patients. It is not a specific test. This is mostly used to assess the condition of the patient after treatment.

Treatment

Surgery: Surgery is applicable when the tumor has been detected at very early stages. But, pancreatic cancer is often advanced when it is detected. Very few pancreatic tumors can be removed by surgery. The standard procedure is called a pancreaticoduodenectomy (Whipple procedure). This surgery is a complicated one and should be performed only by experts. Total and distal pancreatectomy can also be performed. Palliative surgery can also be performed to improve the patient’s condition. Surgical biliary bypass and endoscopic stent placement are performed to remove biliary obstruction.

Surgery can be performed on stage I and stage II cancer. When the tumor has not spread out of the pancreas but cannot be removed, radiation therapy and chemotherapy together may be recommended. Only palliative surgery is performed on Stage III cancer patients.

Chemotherapy: When the tumor has spread (metastasized) to other organs such as the liver (Stage III and Stage IV cancer), chemotherapy alone is usually used. The standard chemotherapy drug is gemcitabine, but other drugs may be used. Gemcitabine can help approximately 25% of patients.

Radiation therapy: Radiation therapy can be of two types of radiation therapy. These are external radiation therapy (beam of radiation given from outside the body by a machine) and internal radiation therapy (radiation given by radioactive substance sealed in catheters or needles that are placed directly into or near the cancer). The preferred type depends on the type and stage of the cancer.

Prognosis

In U.S. among the 44,030 new cases 37,660 deaths have been reported in 2010. These figures reflect the destructive ability of this form of cancer. The five year survival rate of cancer in pancreas is less than five percent. In most cases patients die within 6 -8 months after being diagnosed with pancreatic cancer.

Early detection of pancreatic cancer is essential for treatment. Surgery can be helpful if performed before the disease has metastasized. Once the cancer spreads, only palliative treatment can be provided and time of survival can be increased.

References

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  7. This article was originally published on September 3, 2012 and last revision and update was 9/4/2015.