CANCER OF THE PANCREAS

S. ARCHANA M.Sc., M.Phil.,- Research Assistant
Clinical Research Department
M.V. Hospital for Diabetes
Royapuram

About the Pancreas:

The pancreas is an organ in the abdomen that sits in front of the spine above the level of the belly button. It performs two main functions: - it makes insulin, a hormone that regulates blood sugar levels, and it makes enzymes, which help break down proteins so that they can be more easily absorbed by the body and used for energy. Enzymes leave the pancreas through a system of tubes called "ducts" that connect the pancreas to the intestines.


Pancreatic cancer:

Pancreatic cancer occurs when uncontrolled cell growth begins in the pancreas. Instead of developing into healthy, normal tissue, these abnormal cells continue dividing and form lumps or masses of tissue called tumors. Tumors do not allow the pancreas to function properly. A tumor that stays in one spot and has limited growth is generally considered to be benign.

Malignant tumors form when the cancer cells migrate to other parts of the body through the blood or lymph systems. When a tumor successfully spreads to other parts of the body and grows, invading and destroying other healthy tissues, it is said to have metastasized. This process itself is called metastasis, and the result is a more serious condition that is very difficult to treat.

Because pancreatic cancer is usually diagnosed late into its development, the five-year survival rate after diagnosis is less than 5%.


Causes, incidence, and risk factors:

The exact cause of pancreatic cancer is unknown. It is more common in:

People with diabetes,
People with long-term inflammation of the pancreas (chronic pancreatitis),
Smokers, and Women, and the risk increases with age.

A small number of cases are related to genetic syndromes that are passed down through families.

The incidence of pancreatic cancer appears to be higher in people with increased calorie consumption, high fat and carbohydrate consumption and lower in those with a diet rich in fresh fruit and vegetables.

Symptoms of pancreatic cancer:

A tumor or cancer in the pancreas may grow without any symptoms at first and is often in an advanced stage when first detected.

Early symptoms of pancreatic cancer include:

Dark urine and clay-colored stools
Fatigue and weakness
Jaundice (a yellow color in the skin, mucus membranes, or eyes)
Loss of appetite and weight loss
Nausea and vomiting
Pain or discomfort in the upper part of the belly or abdomen

Other possible symptoms are back pain, blood clots, diarrhea, or indigestion.

Signs and tests:

* Liver function tests show a suppression of bile flow in form of significantly elevated levels of:
Bilirubin (conjugated and total), a compound produced by the breakdown of hemoglobin from red blood cells.
Alkaline phosphatase, an enzyme released into the blood during injury and during such normal activities as bone growth and pregnancy.
Gamma-Glutamyl Tranpeptidase ( GGT ), an enzyme that plays a key role in the pathway for the synthesis and degradation of glutathione.

* Mild increase in amino-transferase, an enzyme that catalyses the transfer of an amino group from a donor molecule to a recipient molecule.

* Hypoalbuminemia (a frequent condition where the albumin in blood serum is abnormally low).

* Ultrasound of the abdomen is the most useful screening test. It gives a lot of information - dilation of the biliary tract which carries bile out of the liver ,enlarged lymph nodes, fluid in the abdominal cavity and so on.

* CT scans like spiral CT and Multi Detector CT (MDCT) are the most advanced imaging methods to diagnose and assess surgery requirements for pancreatic cancer. The accuracy for assessment of surgery is 70 to 79 percent.

* Endoscopic Ultrasonography (EUS) uses a high-frequency ultrasonographic machine on an endoscope (a camera on a tube) to help visualize the pancreas. High-frequency ultrasonography (7.5 – 12 MHZ) can be used to produce very high resolution images. This has proved to be the most sensitive and specific diagnostic test for pancreatic cancer including those smaller than 3 cm. An additional significant advantage is the EUS-guided fine-needle aspiration, which can confirm pancreatic carcinoma at the time of EUS diagnosis.

Stages of Pancreatic Cancer:

After a diagnosis is made, doctors find out how far the cancer has spread to determine the stage of the cancer. The stage determines treatment and informs prognoses. The standard pancreatic cancer staging method is called the TNM (Tumor - Node - Metastasis) system. T indicates the size and direct extent of the primary tumor, N indicates the degree to which the cancer has spread to nearby lymph nodes, and M indicates whether the cancer has metastasized to other organs in the body.

Treatment of pancreatic cancer:

Surgery:

As pancreatic cancer is often advanced when it is first found, very few tumors can be removed by surgery. The standard surgical procedure is called a pancreaticoduodenectomy (Whipple procedure).

This Kausch-Whipple mode of operation involves surgery of the pancreatic head, the duodenum and proximal 10cm of jejunum, the distal stomach, and the common bile along with the gall bladder and cystic duct. This is a major gastrointestinal operation that can last for approximately 4 to 6 hours and requires expert surgical teams.

Surgery however doesn’t kill the patient – the chances for that are between 0 to 5%. The major cause of postoperative morbidity is the occurrence of pancreatic enteric leaks leading to intra-abdominal abscess and pancreatic fistulae.


Adjuvant therapy:

The median survival rate of patients who undergo only surgery is 10 to 20 months with a high rate of local recurrence and problems of the disease spreading to secondary parts. Thus all surgically treated patients should be given supportive therapy.

Radiation therapy:

Radiation therapy is used to fight many types of cancer. It is often used to shrink a tumor as much as possible before surgery. Radiation can also be given after surgery to prevent the cancer from coming back.

For certain types of cancer, radiation are the only treatment needed. Radiation treatment may also be used to provide temporary relief of symptoms, or to treat cancers that cannot be removed with surgery.

There are two forms of radiation therapy:

* External beam radiation is the most common form. This method carefully aims high powered x-rays or particles directly at the tumor from outside the body.
* Internal beam radiation uses radioactive seeds that are placed directly into or near the tumor.

Chemotherapy:

Pain reducing chemotherapy is offered to patients whose cancer cannot be improved with surgery or is a spreading disease.

Different chemotherapy drugs may be given at the same time or after each other. Patients may receive radiation therapy before, after, or while they are getting chemotherapy.

Chemotherapy is most often given in cycles. These cycles may last one day, several days, or a week or more. There will usually be a rest period when no chemotherapy is given between each cycle. A rest period may last for days, weeks, or months.

Prevent pancreatic cancer:

* Stop smoking.


* Eat a diet high in fruits, vegetables, and whole grains.


* Exercise regularly.