Pancreatic cancer is ranked 4th in terms of cancer-associated deaths in the UK. This is particularly as it presents at very advanced stages which are usually incurable. It is mostly occurring in 60-80 year olds.
Pathophysiology
There are a multitude of cells within the pancreas, but the most common type of cancer is a ductal carcinoma (which is an adenocarcinoma). The remainder are exocrine and endocrine tumours which have a better prognosis overall.
The location of the tumour on the pancreas is vital for its presentation and prognosis:
- 60% are head of pancreas
- 20% are body and tail of pancreas
- 20% are diffuse throughout the pancreas
It is generally that a tail of pancreas cancer is more subtle and as a result it presents much later as it is surrounded by less visceral organs and causes less obstruction and invasiveness into the viscera.
⚠️ Risk factors
- Chronic pancreatitis
- Smoking
- Family history
- Obesity & diet (high meat, low fruit and veg diet)
- Lynch syndrome
- Multiple endocrine neoplasia
- Diabetes
- BRCA2 gene
- KRAS mutation
😷 Presentation
- Painless obstructive jaundice in the head of the pancreas due to compression of the CBD (will lead to pale stool and dark urine too) [for head of pancreas].
- Pruritus due to increased bilirubin levels
- Weight loss
- Epigastric pain that may be relieved by sitting forward if the tumour is in the body and tail of pancreas. This is because the body lies in front of the solar plexus.
- Splenomegaly if it is in the tail of pancreas due to obstruction of the splenic vein.
- Steatorrhoea (due to loss of exocrine function)
- Diabetes mellitus (due to loss of endocrine function)
- Atypical back pain
- Vague abdominal pain
- Troussea sign of malignancy - migratory thrombophlebitis.
🔍 Investigations
Patient may seem cachetic, malnourished, jaundiced and an abdominal mass may be present in the epigastric region (but Courvoisier’s Law states that if there is a painless obstructive jaundice with a palpable gallbladder, it is unlikely to be due to gallstones).
- FBC - may indicate anaemia or thrombocytopenia.
- LFTs - with increase bilirubin, ALP and GGT.
- CA19-9 - a tumour marker with high sensitivity for pancreatic cancer but is used to assess response to treatment rather than diagnosis itself.
- Serum lipase - may be raised.
🧰 Management
Pancreatic tumours can be described as resectable, borderline resectable and locally advanced (unresectable) depending on the degree of contact with the surrounding vessels. For adenocarcinoma of the pancreas, radical resection is the only curative measure. However, adjuvant chemo may be used (gemcitabine or 5-FU).
Criteria for resection can include:
- No evidence of involvement of the superior mesenteric artery (SMA) or coeliac arteries.
- No evidence of distant metastases.
- WhIpple’s procedure - for head of pancreas cancer. It involves a pancreaticoduodenectomy, gallbladder removal and CBD removal. The rest of the pancreas is attached to the jejunum and the stomach to the jejunum too. An issue with Whipple’s is dumping syndrome and PUD/ reflux. It has about a 70% on-the-table mortality.
- Distal pancreatectomy ± splenectomy - for tail of pancreas tumour.
- ERCP + stenting - for palliative cases.
🥇 USS is the first line. It may show dilated biliary tree and a pancreatic mass.
🏆 CT scan is the gold standard. We may see a double duct sign which refers to the presence of simultaneous dilatation of the common bile and pancreatic ducts.
EUS for staging.
If the patient is jaundiced, we can send for ERCP or MRCP.
What we have discussed is mainly the adenocarcinoma of the pancreas but their are othe endocrine tumours of the pancreas which may be functional or non-functional based on whether they secrete hormones or not.
Cell Type | Secreted Hormone (name of tumour) | Normal Physiological Function | Features of Functional Tumour |
G cells | Gastrin (gastrinoma) | Stimulates the release of gastric acid | Zollinger-Ellison syndrome, resulting in severe peptic ulcers, refractory to medical treatment, with diarrhoea and steatorrhoea |
α Cells | Glucagon (glucagonoma) | Increase blood glucose concentration | Hyperglycaemia, diabetes mellitus, and necrolytic migratory erythema |
β Cells | Insulin (insulinoma) | Decrease blood glucose concentration | Symptomatic hypoglycaemia, such as sweating or changed mental state, improving with consumption of carbohydrates |
δ Cells | Somatostatin (somatostatinoma) | Inhibits the release of GH, TSH and prolactin from the anterior pituitary, and of gastrin | Diabetes mellitus, steatorrhoea, gallstones (due to inhibition of cholecystokinin), weight loss, and achlorhydria (due to gastrin inhibition) |
Non-islet cells | Vasoactive intestinal peptide (VIPoma)
WDHA syndrome
Verner-Morrison syndrome | Secretion of water and electrolytes into the gut. Relaxation of enteric smooth muscle. | Prolonged profuse watery diarrhoea, severe hypokalaemia, achlorhydria and dehydration. |