|

Pancreatic Cancer

Last updated:

Overview

Pancreatic cancer is the 5th most common cancer in the UK. Its early symptoms are vague and non-specific, and many people present and are diagnosed with advanced disease, resulting in a poor prognosis. Also due to this, a minority of patients (~8%) are eligible for potentially curative surgery. Only 3% survive for 5 years or longer.

One survey found that 40% of people with pancreatic cancer presented to primary care 3 or more times before the diagnosis was made.

Types

Over 90% of pancreatic cancers are adenocarcinomas, with the majority arising in the head of the pancreas. They generally metastasise to the liver, lungs, and peritoneum.

Epidemiology

  • Pancreatic cancer is the 5th most common cancer in the UK
  • The annual incidence of pancreatic cancer in the UK is ~9600
  • Pancreatic cancer is most commonly seen in people aged 65-75 years old

Risk Factors

  • Increasing age – peak incidence is 65-75 years old
  • Smoking – around 1 in 5 cases are thought to be associated with smoking
  • Family history of pancreatic cancer
  • Hereditary cancer syndromes:
  • Chronic pancreatitis:
    • The risk is difficult to assess as factors such as smoking increase the risk of chronic pancreatitis and pancreatic cancer
  • Diabetes mellitus – pancreatic cancer itself can cause diabetes mellitus

Presentation

Overview

The early symptoms of pancreatic cancer are often vague and non-specific. Most patients present with advanced disease. Features include:

  • Vague epigastric abdominal pain/discomfort – an early feature, around 75%:
    • The pain may radiate to the back and can be worse when lying down and improve when sitting forward
    • May be overlooked or missed
  • Painless obstructive jaundice – the classic feature, around ~70%:
    • Obstructive jaundice features include: pale stools, dark urine, and pruritus and cholestatic liver function tests (LFTs, discussed below)
    • Vague abdominal pain may occur with the jaundice
    • Suggests advanced disease and occurs when cancer in the head of the pancreas obstructs the common bile duct

Other features of advanced disease:

  • Unexplained weight loss – around 90%:
    • There may be associated anorexia
  • Abdominal masses – from most to least common:
    • Hepatomegaly – suggests hepatic metastases
    • Courvoisier’s law – painless palpable gallbladder and jaundice
    • Epigastric mass – due to the primary tumour
  • Nausea, vomiting, and early satiety:
    • Due to surrounding gastrointestinal organs being compressed by a tumour
  • Loss of pancreatic exocrine function:
    • Steatorrhoea and malabsorption
  • Loss of pancreatic endocrine function:
    • New-onset diabetes (polyuria, polydipsia etc.)
  • Back pain:
    • Suggests retroperitoneal metastases or invasion of the surrounding nerves (coeliac plexus)
  • Trousseau’s sign (migratory thrombophlebitis):
    • Recurrent episodes of blood vessel inflammation due to thrombi (thrombophlebitis) in different locations over time (migratory)
    • Cancer generally leads to hypercoagulability, Trousseau’s sign is more common in pancreatic cancer compared to other cancers

Referral

Urgently refer people via a suspected cancer pathway if they are ≥40 years old and have jaundice.

Consider a direct access CT scan (or ultrasound if CT unavailable) within 2 weeks for people ≥60 years old with weight loss and any of the following:

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

Investigations

Overview

Key investigations include:

  • Pancreatic protocol CT scan – the first-line investigation of choice:
    • Imaging may show a ‘double duct’ sign – dilatation of the common bile and pancreatic ducts most commonly due to pancreatic cancer and cholangiocarcinoma
  • Fluorodeoxyglucose-positron emission tomography/CT (FDG‑PET/CT):
    • If the diagnosis is unclear after a pancreatic protocol CT scan
  • Endoscopic ultrasound (EUS) with EUS‑guided tissue sampling:
    • If the diagnosis is unclear after a pancreatic protocol CT scan, may be performed alongside FDG-PET/CT
    • May identify tumour and allow tissue collection for histology

Other tests

Other investigations may include:

  • Full blood count (FBC):
    • May show anaemia, thrombocytosis, or both
  • Liver function tests (LFTs):
    • Shows cholestatic liver function tests (elevated bilirubin, ALP, gamma-GT)
    • If the liver is involved, transaminases may be elevated
  • Serum glucose:
    • May show hyperglycaemia
  • Carbohydrate 19-9 (CA19-9):
    • May be elevated, limited diagnostic value
    • May be used as a baseline to monitor responses to treatment
  • Endoscopic retrograde cholangiopancreatography (ERCP):
    • Used to relieve biliary obstruction and biliary brushings may be taken for cytology

Differential Diagnoses

Cholangiocarcinoma

  • Both can present with painless obstructive jaundice which can make them difficult to distinguish clinically
  • CA 19-9 can be elevated in both
  • Epigastric or back pain is less common in cholangiocarcinoma compared to pancreatic cancer

Chronic pancreatitis

  • Distinguishing between the two may be difficult as both can cause nausea, abdominal pain, malabsorption, and pancreatic endocrine insufficiency, however
  • Chronic pancreatitis more commonly has dull epigastric pain that may radiate to the back and is worse ~30 minutes after a meal and does not usually present initially with painless obstructive jaundice compared to pancreatic cancer

Management

Overview

Since many patients are diagnosed with advanced disease, around 8% of people are eligible for potentially curative surgery. Treatment is coordinated by a multidisciplinary team and may involve:

  • Whipple’s resection (pancreaticoduodenectomy) and adjuvant chemotherapy for resectable cancer of the head of the pancreas

Complications

  • Obstructive jaundice:
    • When cancer of the head of the pancreas obstructs the common bile duct
  • Duodenal obstruction:
  • Severe, persistent abdominal pain:
    • Due to pressure effects of the tumour on surrounding structures, pancreatic inflammation, or other complications such as duodenal obstruction
  • Acute cholangitis:
    • Due to obstruction of the bile duct resulting in inflammation and infection
  • Trousseau’s sign (migratory thrombophlebitis), deep vein thrombosis, and pulmonary embolism:
    • Recurrent episodes of blood vessel inflammation due to thrombi (thrombophlebitis) in different locations over time (migratory)
    • Cancer generally leads to hypercoagulability, Trousseau’s sign is more common in pancreatic cancer compared to other cancers

Prognosis

  • Average life expectancy post-diagnosis is around 4-6 months
  • Only 3% of people survive for 5 years or longer
  • In the ~8% of people who are eligible for surgery, 5-year survival rates are up to 30% with surgery and adjuvant chemotherapy

Author