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Cancer of Pancreas

Pancreatic cancer is relatively uncommon. It develops in about 1 in 10,000 people each year

in the UK. There are several types of pancreatic cancer, but more than 9 in 10 cases are

'ductal adenocarcinomas'.

Ductal adenocarcinoma of the pancreas

This type of cancer develops from a cell which becomes cancerous in the pancreatic duct.

This multiplies and a tumour then develops in and around the duct. As the tumour enlarges:

It can block the bile duct or the main pancreatic duct. This stops the drainage of bileand/or pancreatic fluid into the duodenum.

It invades deeper into the pancreas. In time it may pass through the wall of thepancreas and invade nearby organs such as the duodenum, stomach or liver.

Some cells may break off into the lymph channels or bloodstream. The cancer maythen spread to nearby lymph nodes or spread to other areas of the body (metastasise).

Causes

Overall, estimates indicate that 40% of pancreatic cancer cases are sporadic in nature.

Another 30% are related to smoking, and 20% may be associated with dietary factors. Only

5-10% are hereditary in nature. Fewer than 5% of all pancreatic cancers are related to

underlying chronic pancreatitis.

Clinical Diagnosis

The early clinical diagnosis of pancreatic cancer is fraught with difficulty. Unfortunately, the

initial symptoms are often quite nonspecific and subtle in onset.

Patients typically report the gradual onset of nonspecific symptoms such as anorexia,malaise, nausea, fatigue, and mid-epigastric or back pain.

Significant weight loss is a characteristic feature of pancreatic cancer. Pain is the most common presenting symptom in patients with pancreatic cancer.

Typically, it is mid epigastric in location, with radiation of the pain sometimes

occurring to the mid- or lower-back region. Radiation of the pain to the back is

worrisome, as it indicates retroperitoneal invasion of the splanchnic nerve plexus by

the tumor. Often, the pain is unrelenting in nature with night-time pain often being apredominant complaint. Some patients may note increased discomfort after eating.

The pain may be worse when the patient is lying flat.

Weight loss may be related to cancer-associated anorexia and/or subclinicalmalabsorption from pancreatic exocrine insufficiency caused by pancreatic duct

obstruction by the cancer. Patients with malabsorption usually complain about

diarrhea and malodorous, greasy stools. Nausea and early satiety from gastric outlet

obstruction and delayed gastric emptying from the tumor may also contribute to

weight loss.

The most characteristic sign of pancreatic carcinoma of the head of the pancreasis painless obstructive jaundice.

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o Patients with this sign may come to medical attention before their tumor growslarge enough to cause abdominal pain.

o These patients usually notice a darkening of their urine and lightening of theirstools before they or their families notice the change in skin pigmentation.

Physicians can usually recognize clinical jaundice when the total bilirubin

reaches 2.5-3 mg%. Patients and their families do not usually notice clinical

jaundice until the total bilirubin reaches 6-8 mg%. Urine darkening, stool

changes, and pruritus are often noticed by patients before clinical jaundice.

o Pruritus may accompany and often precedes clinical obstructive jaundice.Pruritus can often be the patient's most distressing symptom.

Physical signs

Physical signs of pancreatic cancer may include weight loss, jaundice, abdominal mass,

epigastric tenderness, palpable gallblader, and hepatomegaly; at least half of patients have no

physical findings.

Diagnostic Procedures

Initial assessment

There are many causes of jaundice and of the other symptoms listed above. Therefore, some

initial tests are usually arranged if patients develop jaundice or the other symptoms listed

above. Typically, these include an ultrasound scan of the abdomen and various blood tests.

These initial tests can usually give a good idea if the cause of jaundice is a blockage from the

head of the pancreas.

Assessing the extent and spread

A CT scan (computerised tomography) is a commonly used test to assess pancreaticcancer.

An MRI scan is sometimes done. An endoscopic ultrasound (EUS). A chest X-ray. A laparoscopy. This is using a laparoscope. A laparoscope is passed into the abdomen

through a small incision (cut) in the skin.

Biopsy

If a biopsy is thought to be needed then one way to get a sample from the pancreas is to take

the biopsy sample when you have an endoscopy. This is done by passing a thin grabbing

instrument down a side channel of the endoscope (gastroscope). Alternatively, sometimes a

biopsy is done at the same time as having a scan. It can take two weeks for the result of a

biopsy.

Treatment

Surgery

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If the cancer is at an early stage, then there is a modest chance that surgery can be curative.

(An early stage means a small tumour which is confined to within the pancreas and has not

spread to the lymph nodes or other areas of the body).

If the tumour is in the head of the pancreas then an operation to remove the head ofthe pancreas may be an option. This is a long and involved operation as thesurrounding structures such as the duodenum, stomach, bile duct, etc, need to be

rearranged once the head of the pancreas is removed.

If the tumour is in the body or tail of the pancreas then removal of the affected sectionof the pancreas is sometimes an option.

The reason why the chance of cure is only modest is because in a number of cases thought to

be in an early stage, some cells have already spread to other parts of the body but are not yet

detectable by scans or other staging tests. In time they grow into secondary tumours.

If the cancer is at a later stage then surgery is not an option to cure the disease. Some surgical

techniques may still have a place to ease symptoms. For example, it may be possible to ease

jaundice caused by a blocked bile duct. A 'bypass' procedure may be used, or a stent may be

inserted into the bile duct. (A stent is a small rigid tube made of plastic or metal which aims

to keep a duct or channel open. It is usually inserted by instruments attached to an

endoscope.)

Chemotherapy

Chemotherapy is a treatment of cancer by using anti-cancer drugs which kill cancer cells or

stops them from multiplying. When chemotherapy is used in addition to surgery it is known

as 'adjuvant chemotherapy'.Radiotherapy

Radiotherapy is a treatment which uses high energy beams of radiation which are focused on

cancerous tissue. This kills cancer cells, or stops cancer cells from multiplying. Radiotherapy

is not commonly used to treat pancreatic cancer.

Overall survival is less than 5% at 5 years. Survival for distal lesions where radical

pancreaticoduodenectomy is possible ranges from 16-68% at 5 years with an average of 42%.

Midduct cancer for the most part is much less common and generally unresectable; 5-year

survival is less than 5%. Carcinomas of the proximal ducts are resectable in only 30% to 40%

of cases. There are some reported 5-year survivors; mean survival is 30 months.