Pathology of Pancreas, Gallbladder and Extrahepatic biliary tree Flashcards
What are gallstones made of?
Cholesterol
Bile pigment
Mostly they are mixed
- calcium
How are gallstones diagnosed?
10% have enough calcium for X-Ray
Most are seen on ultrasound
What are the components of bile?
97% water Cholesterol Bile acids Phospholipids Bile pigment (bilirubin)
How are gallstones formed?
Bile becomes lithogenic for cholesterol if there is excessive secretion of cholesterol or decreased secretion of bile salts
Excessive secretion of bilirubin (e.g. haemolytic anaemia) can cause precipitation in concentrated bile in the gallbldder
What is acute cholecystitis?
Inflammation of the gallbladder
- normally caused when a gallstone blocks the cystic duct causing supersaturation of bile and chemical irritation
What are the signs and symptoms of acute cholecystitis?
Severe RUQ pain Tenderness Fever (sepsis) Leucocytosis Normal serum amylase
What is the outcome for cholecystitis?
Usually resolves spontaneously but can progress to empyema. gangrene and rupture
What is the pathophysiology of chronic cholecystitis?
A sequel to repeated attacks of acute cholecystitis
This damages the wall, making it thick and fibrotic
The inflammation is secondary to chemical damage (supersaturated bile) rather than a bacterial infection
What is a gallbladder mucocele?
Overdisteneded gallbladder with an epithelial lining filled with mucoid or clear and water content
What is the pathophysiology of a gallbladder mucocele?
Usually non-inflammatory
Results in outlet obstruction of the gallbladder (commonly an impacted stone in the neck or cystic duct)
The wall becomes pale, smooth and fibrotic
Name some of the causes of acute pancreatitis.
Gallstones Alcohol abuse (main) Post-ERCP Hypercalcaemia Drugs (azothioprine) Mumps
How does acute pancreatitis present?
Severe upper abdominal pain - pain not just localised to the gallbladder Fever Leucocytosis Rasied serum amylase
What is the pathophysiology of acute pancreatitis?
Blockage of the bile duct (e.g. gallstone at the hepatopancreatic ampulla of Vater)
The causes bile reflux back into the pancreatic duct
The digestive enzymes irritate the cells of the pancreas = pancreatitis
What is acute hemorrhagic pancreatitis?
Acute inflammation and necrosis of pancrease parenchyma, focal enzymic necorisis of the pancreatic fat and vessel necrosis (haemorrhage)
- digestion of the vascular walls results in thrombosis and haemorrhage
- lipase activation produces necrosis of fat tissue in the pancreatic interstitium and peri-pancreatic spaces
What is a pancreatic abscess?
A potential complication of acute pancreatitis
When pancreatic necrosis becomes infected (an avascular haemorrhagic pancreas is a good culture medium)
How is a pancreatic abscess treated?
Drainage or necrosectomy plus antibiotics
What is the pathophsyiology of chronic pancreatitis?
Long-standing inflammation of the pancreas
- either episodes of acute inflammation or
- chronic damage with persistent pain or malabsorption
Caused by ductal obstruction
Progressive, irreverisble fibrotic destruction of the pancreatic secretory parenchyma and areas of ductal dilation and stricture
What are the signs and symptoms of chronic pancreatitis?
Episodic, epigastric abdominal pain - episodes stop once the acinar cells have been destroyed (6-10 years) No pain and malabsorption Steatorrhoea Diabetes
What is the difference between a cyst and a pseudocyst?
Cysts have epithelial linings
- can’t tell the difference on imaging
What is a pseudocyst?
Potential complication of acute pancreatitis
Commonly arises in the lesser sac
Contains a high concentration of pancreatic enzymes
May resolve by itself or require draining into the stomach (transmural drainage)
What are the possible differentials when you see a pancreatic cyst?
Mucinous cystic neoplasm - benign, but has an invasive component Intraductal papillary mucinous neoplasm - in continuity with the main pancreatic duct or side branch duct - dysplastic papillary lining, secreting mucin - risk of malignancy Serous cystadenoma - no mucin production - benign
What are the signs and symptoms of carcinoma of the pancreas?
Painless obstructive jaundice
- if in head of pancreas
- painless as it occurs slowly and the gallbladder isn’t contracting forcefully against the blockage
Abdominal pain due to pancreatic insufficiency or nerve invasion
Radiology may show the double duct sign (tumour in the head of the pancreas obstructing the bile and pancreatic ducts)
- you would also see duct dilation with no gallstone presence
What is a Whipple’s resection?
When a tumour of the head of the pancreas is removed
- curative intent
Can’t have any metastases
- as most people present late, only 10% of patients are suitable
75% of tumours are incompletely excised
20 month survival rate after operation
What is neo-adjuvant therapy?
Chemotherapy
- the administration of a therapeutic agent before the main treatment
- e.g. trying the shrink the tumour before surgery
Give some examples of neo-adjuvant therapy for carcinoma of the pancreas?
Folfirinox chemotherapy
- limited improvement in metastatic disease
What is a pancreatic endocrine tumour?
A tumour of the islets in the pancreas
- some secrete hormones (functional)
- most common function tumour is an insulinoma, which presents with hypoglycaemia
Rare
Most insulinomas are bengin
Malignant endocrine tumours have better prognosis than pancreatic carcinoma
What is carcinoma of the ampulla of Vater?
A malignant tumour in the last 2cm of the common bile duct, where it passes through the duodenal wall
Presents early due to bile obstruction
May arise from a pre-existing adenoma (intestinal)
How is carcinoma of the ampulla of Vater treated?
Whipple’s resection
- 25% 5 year survival
What is a Cholangiocarcinoma?
A tumours of the connective tissues of the bile ducts
Classified as wither intra- or extra-hepatic depending on the origin
Why is it hard to diagnose a Cholangiocarcinoma?
Has a similar histology to metastitic adenocarcinoma
In the same organ are hepatocellular carcinoma
Extrahepatic carcinoma’s have similar morphology and prognosis to pancreatic carcinoma
What is the treatment of a Cholangiocarcinoma?
Whipple’s operation to remove the common bile duct and involved pancreas and duodenum
No chemotherapy as of yet
Describe a carcinoma of the gallbladder.
Rare Gallstones are present in 80% of cases Adenocarcinoma Bad prognosis unless found incidentally in a gallbladder removed for chronic cholecystitis - complete excision
