Pancreatic Cancer Flashcards
What age group are more likely to get pancreatic cancer?
> 40
What are risk factors for pancreatic cancer?
1) Cigarette smoking
2) Diet rich in animal fats and protein
3) Obesity
Family history
4) Hereditary syndromes e.g. hereditary pancreatitis, Lynch syndrome, Peutz-Jeghers
What are symptoms of pancreatic cancer?
1) Dull epigastric pain radiating to middle back
2) Obstructive jaundice (can be painless)
3) Weight loss
4) Sickness/indigestion
5) Change in bowel habit - steatorrhoea
6) Diabetes (recent onset)
7) Blood clots e.g. common cause of unexplained occult DVT - migratory thrombophlebitis (Trousseau sign)
In which cancers in dull epigastric pain radiating to the middle back especially common?
Cancer in the body and tail of pancreas
Why does pain occur in pancreatic cancer?
- The coeliac plexus is around the area of the body and tail of the pancreas
- So any involvement around that area will lead to very severe abdominal pain
In what other condition to pts get coeliac plexus pain?
Chronic pancreatitis
How can you relieve coeliac plexus pain?
Block the coeliac plexus by various injections into the plexus
Which patients get obstructive jaundice?
In pts with cancer of the head of the pancreas
What are symptoms of obstructive jaundice?
1) Pale stool
2) Dark urine
3) Severe itching (bad scratch marks)
Why does steatorrhoea occur in pancreatic cancer?
Fatty diarrhoea bc don’t have pancreatic enzymes to digest fat
What other types of cancer come under cancer of the head of the pancreas?
- Can be cancer of the bile duct as well e.g. cholangiocarcinoma bc the bile duct goes to the head of the pancreas as well
- Doesn’t always mean exocrine tumour of the pancreas
Describe the entero-hepatic re circulation of bile
1) Urobilinogen is formed in the intestines by bacterial action on bilirubin (BR excreted during fatty meal)
2) Urobilinogen is reabsorbed back in the terminal ileum to the liver and converted into urobilin which is excreted by the kidney (yellow colour of urine)
3) The urobilinogen in the intestine is reduced to brown stercobilin and excreted in faeces (brown colour of faeces)
What causes obstructive jaundice?
Biliary obstruction
- If there is a blockage to the biliary system e.g. common bile duct, bile cannot get excreted into the small bowel
- Therefore there will be no urobilinogen
What are the consequences of biliary obstruction?
- Decreased conjugated bilirubin reaches the intestine for conversion to urobilinogen
- Decreased urobilin in urine
- Decreased stercobilin in faeces (pale stool)
- Increased conjugated bilirubin in blood bc it is instead excreted directly from the liver to the circulation (excreted in urine - dark urine)
Describe LFTs in hepatitis
- High ALT and AST due to hepatocellular damage
- Low ALP
Describe LFTs in obstructive jaundice
- Low ALT and AST
- High ALP
What is the main investigation of obstructive jaundice?
Ultrasound scan of the liver and biliary system
Why do you do an ultrasound scan in obstructive jaundice?
- Shows whether biliary trees are dilated
- If they are, obstruction either from the outside, within the wall (cholangiocarcinoma) or inside the lumen (gall stone)
What are the differential diagnoses if there is biliary tree dilation on US?
- Surgical causes of obstructive jaundice
- Stones, tumours
What are the differential diagnoses if there is no biliary tree dilation on US?
- Hepatocellular causes of obstructive jaundice
- Hepatitis, drug induced reaction
What is Courvoisier’s law?
In the presence of a palpably enlarged gall bladder which is non-tender and there is mild painless jaundice the cause is unlikely to be gallstones
Explain Courvoisier’s law
With gallstones, repeated infection causes fibrosis of the gall bladder, therefore it is not palpable
What investigations would you do for pancreatic cancer?
Blood tests
- FBC, U&E, LFTs
- CA 19-9 (cancer antigen 19-9)
What is the pancreatic tumour marker in blood?
CA 19-9
What scan would you do to stage pancreatic cancer?
CT scan - shows size, position and spread of tumour
What might you see on a CT scan with pancreatic cancer?
- Poorly defined hypodense mass
- Extensive surrounding desmoplastic reaction (fibrosis, adhesion)
What is CA 19-9 a tumour marker for?
Pancreatic cancer
What are the tumour stages of pancreatic cancer?
T1 - < 2cm
T2 - < 4cm
T3 - > 4cm
T4 - involves nearby large blood vessels or organs
What scan would you do to plan treatment for pancreatic tumour?
CT
What types of pancreatic cancers tend to be resectable?
- < 3cm
- Head of the pancreas cancer - tends to present at an early stage with jaundice (remove whole cancer + head of pancreas)
What types of pancreatic cancers are less likely to be resectable?
- Cancer involving body or tail of the pancreas - tends to present late and more advanced
- Spread to nearby lymph nodes or major blood vessels - can’t really cut out a major blood vessel around that area
What are the 3 types of surgery for pancreatic cancer?
1) Pyloric preserving pancreatoduodenectomy (PPPD)
2) Whipple’s procedure
3) Total pancreatectomy
Are most pancreatic cancers exocrine or endocrine adenocarcinomas?
Exocrine adenocarcinomas - secrete digestive enzymes
What are the 3 types of exocrine adenocarcinomas?
1) Ductal adenocarcinomas (> 80%)
2) Cystic tumours - most benign, better prognosis
3) Cancer of acinar cells (produce pancreatic juices at ends of ducts) - younger age, slower growing, better prognosis
Describe a PPPD
- For cancer in the head of the pancreas
- Need to remove the whole duodenum bc of the pancreatic drainage to the duodenum
- Then reconnect everything to the jejunum
- Preserve the pylorus bc the pylorus regulates gastric emptying/discharge into the small bowel - better function if keep pylorus
Describe Whipple’s procedure (pancreaticoduodenectomy)
- Performed for resectable lesions in the head of the pancreas
- Pylorus resected
- Join stomach directly onto jejunum
- Don’t have that more refined control of digestion
Describe a total pancreatectomy
- Remove whole pancreas, duodenum, pylorus and gall bladder
- Join stomach to the jejunum
- Join bile duct directly to small bowel
Describe pancreatic neuroendocrine tumours (PNETS) or islet cell tumours
- Named after hormone they produce e.g. gastrin, insulin, somatostatin, VIP, glucagon - strange symptoms
- ⅔ PNETS non-functioning - no hormone production, no symptoms
- Better prognosis than exocrine
