Pancreatic Cancer

Pancreatic cancer is often diagnosed late and has a very poor prognosis. The vast majority are adenocarcinomas, and most occur in the head of the pancreas (as opposed to the body and tail). Once a tumour in the head of the pancreas grows large enough it can compress the bile ducts, resulting in obstructive jaundice. 

Pancreatic cancers tend to spread and metastasise early, particularly to the liver, then to the peritoneum, lungs and bones. The average survival, when diagnosed with advanced disease, is around 6 months.

When caught early, the cancer is isolated to the pancreas and surgery is possible, the 5-year survival is still around 25% or less. 

 

Presentation

Painless obstructive jaundice is a key presenting feature that should make you immediately consider pancreatic cancer (the key differential is cholangiocarcinoma). This occurs when a tumour at the head of the pancreas compresses the bile ducts, blocking the flow of bile out of the liver. It presents with:

  • Yellow skin and sclera
  • Pale stools
  • Dark urine
  • Generalised itching

 

The other presenting features for pancreatic cancer can be vague:

  • Non-specific upper abdominal or back pain
  • Unintentional weight loss
  • Palpable mass in the epigastric region
  • Change in bowel habit
  • Nausea or vomiting
  • New-onset diabetes or worsening of type 2 diabetes

 

TOM TIP: It is worth noting that a new onset of diabetes, or a rapid worsening of glycaemic control type 2 diabetes, can be a sign of pancreatic cancer. Keep pancreatic cancer in mind if a patient in your exams or practice has worsening glycaemic control despite good lifestyle measures and medication.

 

Referral

The NICE guidelines on suspected cancer (last updated January 2021) give the criteria for when to refer for suspected pancreatic cancer:

  • Over 40 with jaundice – referred on a 2 week wait referral
  • Over 60 with weight loss plus an additional symptom (see below) – referred for a direct access CT abdomen

 

The NICE guidelines suggest a GP referral for a direct access CT abdomen (or ultrasound if not available) to assess for pancreatic cancer if a patient has weight loss plus any of:

  • Diarrhoea
  • Back pain
  • Abdominal pain
  • Nausea
  • Vomiting
  • Constipation
  • New-onset diabetes

 

TOM TIP: As far as I am aware, suspected pancreatic cancer is the only scenario where GPs can refer directly for a CT scan. Whenever guidelines and clinical practice have notable exceptions like this it is worth taking note of, as these make good facts for examiners to test your knowledge on.

 

Named Signs

Courvoisier’s law states that a palpable gallbladder along with jaundice is unlikely to be gallstones. The cause is usually cholangiocarcinoma or pancreatic cancer.

Trousseau’s sign of malignancy refers to migratory thrombophlebitis as a sign of malignancy, particularly pancreatic adenocarcinoma. Thrombophlebitis is where blood vessels become inflamed with an associated blood clot (thrombus) in that area. Migratory refers to the thrombophlebitis reoccurring in different locations over time.

 

Investigations

Diagnosis is based on imaging (usually CT scan) plus histology from a biopsy.

Staging CT scan involves a full CT thorax, abdomen and pelvis (CT TAP). This is used to look for metastasis and other cancers.

CA 19-9 (carbohydrate antigen) is a tumour marker that may be raised in pancreatic cancer. It is also raised in cholangiocarcinoma and a number of other malignant and non-malignant conditions.

Magnetic resonance cholangio-pancreatography (MRCP) may be used to assess the biliary system in detail to assess the obstruction. 

Endoscopic retrograde cholangio-pancreatography (ERCP) can be used to put a stent in and relieve the obstruction, and also obtain a biopsy from the tumour.

Biopsy may be taken through the skin (percutaneous) under ultrasound or CT guidance, or during an endoscopy under ultrasound guidance.

 

Management

Management will be decided at a hepatobiliary (HPB) MDT meeting. 

Surgery to remove the tumour is more likely to be considered with small tumours isolated in the head of the pancreas (about 10% of cases). There are a number of surgical options depending on the location of the tumour:

  • Total pancreatectomy
  • Distal pancreatectomy
  • Pylorus-preserving pancreaticoduodenectomy (PPPD) (modified Whipple procedure)
  • Radical pancreaticoduodenectomy (Whipple procedure)

 

In most cases, curative surgery is not possible. Palliative treatment may involve:

  • Stents inserted to relieve the biliary obstruction
  • Surgery to improve symptoms (e.g., bypassing the biliary obstruction)
  • Palliative chemotherapy (to improve symptoms and extend life)
  • Palliative radiotherapy (to improve symptoms and extend life)
  • End of life care with symptom control

 

Whipple Procedure

A Whipple procedure (pancreaticoduodenectomy) is a surgical operation to remove a tumour of the head of the pancreas that has not spread. A Whipple procedure is a massive operation so patients need to be in good baseline health. It involves the removal of the:

  • Head of the pancreas
  • Pylorus of the stomach
  • Duodenum
  • Gallbladder
  • Bile duct
  • Relevant lymph nodes

 

A modified Whipple procedure involves leaving the pylorus in place. It is also known as a pylorus-preserving pancreaticoduodenectomy (PPPD).

 

Last updated May 2021