Histopathology 7 - Diseases of the pancreas and gall bladder Flashcards
Recall the mnemonic for the causes of acute pancreatitis
I GET SMASHED
Idiopathic (15%)
Gallstones (50%)
Ethanol (33%)
Trauma
Steroids
Mumps
Autoimmune
Scorpion sting
Hyperlipidaemia/hypercalcaemia/hyperparathyroidism
ERCP
Drugs
Recall two causes of pancreatitis via duct obstruction
Gallstones Alcohol (via spasm/ oedema of Sphinter of Oddi)
Recall the pathophysiology of injury seen in acute pancreatitis
- Enzymes activated
- Acinar necrosis
- Enzyme release
Can cause anything from stromal oedema to haemorrhagic necrosis (**coagulative necrosis)
What are the 3 patterns of injury that may be seen in acute pancreatitis?
Periductal (necrosis of acinar cells near ducts) - caused by obstruction
Perilobular (necrosis at the edges of lobules) - caused by poor blood supply
Panlobular (develops from either of the above)
Why are yellow/white foci seen in acute pancreatitis?
Lipases cause fat necrosis
Calcium ions bind to free fatty acids forming soaps (which are white yellow)
What is a pseudocyst?
Dilated space with no epithelial lining
A psuedocyst can increase the chances of having an abscess
What is a cyst?
Dilated space lined by epithelium
Recall 2 pancreatic and 3 systemic complications of acute pancreatitis
Pancreatic: pseudocyst + abscess
Systemic: shock, hypoglycaemia, hypocalcaemia
Recall 4 complications of chronic pancreatitis
Malabsorption
Diabetes mellitus
Pseudocysts
Carcinoma of the pancreas
What is contained within a pancreatic pseudocyst?
Pancreatic enzymes and necrotic material (which is why it’s so bad when they perforate - it causes peritonitis)
Causes of chronic pancreatitis- what is the most common?
- Metabolic/ Toxic (2):
a) ALCOHOL (80%)
b) Haemochromatosis- iron overload (bronzed diabetes) - Duct Obstruction (3):
a) Gallstones
b) Abnormal pancreatic duct anatomy
c) Cystic fibrosis (mucoviscoidosis) - Tumours
- Idiopathic
- Autoimmune
DIfference in pathology between acute and chronic pancreatitis
Pattern of Injury- distinguishes chronic pancreatitis from acute pancreatitis:
Chronic inflammation with:
parenchymal (functional tissue) fibrosis
→ loss of parenchyma
Duct strictures with:calcified stones
→ secondary dilatations
Histology of chronic pancreatitis:
- no acini
- fibrous tissue
- remaining ducts and islets of langerhans are prominent
Complications of chronic pancreatitis
Malabsorption (exocrine dysfunction)
Diabetes mellitus- fibrosis can overwhelm the islets of langerhans → DM
Pseudocysts, abscess
Pancreatic calcifications
Carcinoma of the pancreas
Which immunoglobin is implicated in autoimmune acute pancreatitis?
IgG4
What type of cancer makes up 85% of pancreatic neoplasms?
Ductal carcinoma
What are the different types of pancreatic tumour?
Carcinomas:
- Ductal
- Acinar
Cystic neoplasms:
- Serous cystadenomas
- Mucinous cystic neoplasms
Pancreatic neuroendocrine tumours (Islet cell tumours)
What mutation is very common in ductal carcinoma?
K-Ras
Tumour marker of pancreatic cancer
CA-19-9
Risk factors for pancreatic ductal carcinoma
smoking
BMI and dietary risk factors
Chronic pancreatitis
Diabetes
What are the 2 types of precancerous dysplastic ductal lesions in the pancreas?
- PanIn (pancreatic intraductal neoplasm)
- Intraductal mucinous papillary neoplasm
**remember PanIn
Which type of tumour has a “gritty and grey” macroscopic appearance?
Ductal adenocarcinoma
What is the typical microscopic appearance of ductal carcinoma of the pancreas?
Mucin-secreting glands set in desmoplastic stroma
stroma that arises in response to cancer - makes it hard and gritty
Define adenocarcinoma
Mucin-secreting glands set in desmoplastic stroma (means: strong stromal reaction)
Recall 3 complications of ductal carcinoma
- Liver metastasis
- Chronic pancreatitis
- Venous thrombosis (“migratory thrombophlebitis”/ Trousseau syndrome) = mucin activating coagulation in circulatory system causing thrombosis
