Histopathology 9: Pancreatic pathology Flashcards
Which 2 mediators control enzyme and alkali release from the pancreas ?
Secretin - released by S cells in the duodenum causes pancreatic HCO3- secretion
CCK- released by I cells in the duodenum causes pancreatic release of digestive enzymes
Which cells release glucagon ?
Alpha cells
Which cells release somatostatin ?
Delta cells
What type of hypersensitivity reaction is T1DM ?
Type 4 delayed T cell mediated
List the causes of Acute pancreatitis ?
I GET SMASHED
Idiopathic Gall stones Ethanol Trauma Steroids Mumps Auto-immune Scorpion venom Hyperlipidaemia ERCP Drugs- Thiazide diuretics
Which blood test is most sensitive for Acute pancreatitis ?
Serum Lipase
List 4 causes of chronic pancreatitis ?
Cystic fibrosis
Alcoholism
Pancreatic duct obstruction - stones /cancer
Auto-immune
Describe the histology of chronic pancreatitis ?
- Dilated ducts
- Fibrosis
- calcification
- loss of exocrine tissue
A patient presents with significant weight loss, abdominal pain, multifocal fat necrosis and polyarthralgia. Histopathology: Eosinophilic granular cytoplasm, immune reactivity for lipase
Most likely diagnosis ?
Acinar cell carcinoma
neoplasm that releases lots of lipase
A patient presents with epigastric pain that radiates to the back, he’s jaundiced and appears cachectic. An abdominal mass is felt on examination.
Most likely diagnosis ?
Ductal adenocarcinoma of the pancreas
Where in the pancreas do Ductal adenocarcinomas tend to occur ?
Head of the pancreas
what is courvoisiers law?
Presence of a palpable enlarged gallbladder, with painless jaundice means gallstones are unlikely.
What is the tumour marker for pancreatic cancer ?
CA19.9
Histopathology: Cells arranged in nests or trabecular with granular cytoplasm.
Hypoglycaemic attacks.
Most likely diagnosis ?
Islet cell tumour- Insulinoma
List 3 types of neuroendocrine islet cell tumours ?
- Insulinoma
- Gastrinoma
- VIPoma
Which syndrome is associated with gastrinomas
Zollinger ellison syndrome
What are Rokitansky-Aschoff sinuses ?
Cholecystitis causes fibrosis which means the gallbladder is contracting against an obstruction. This pressure causes diverticula to form which are known as Rokitansky-Aschoff sinuses.
what are the 2 components of the exocrine parts of the pancreas
ductal
acinar - where enzymes are made
define acute pancreatitis
acute inflammation of the pancreas caused by the aberrant release of pancreatic enzymes
describe how duct obstruction causes acute pancreatitis
gallstone distal to where CBD and pancreatic ducts join leads to reflux of bile up the pancreatic duct followed by damage to acini and release of proenzymes which become activated
describe different patterns of injury in acute pancreatitis
periductal - necrosis of acinar cells near the ducts (usually secondary to obstruction)
perilobular - necrosis at the edges of the lobules (usually due to poor blood supply)
panlobular - develops from worsening of periductal or perilobular inflammation
pathway of inflammation in acute pancreatitis
activated enzymes - acinar necrosis - enzyme release
lipase release - fat necrosis
calcium binds - saponification
what are complications of acute pancreatitis
pancreatic pseudocysts formation
abscess
systemic - shock, hypoglycaemia, hypocalcemia
features of chronic pancreatitis
caused by: alcohol, haemochromatosis, gallstones, abnormal pancreatic duct anatomy, CF, tumours, idiopathic
chronic inflammation with parenchymal fibrosis and loss of parenchyma
duct strictures with calcified stones with secondary dilations
list complications of chronic pancreatitis
malabsorption
DM
pseudocysts (lined by fibrous tissue, contains fluid risk in pancreatic enzymes or necrotic material)
carcinoma of the pancreas
describe features of AI pancreatitis
IgG4 related disease
large numbers of IgG4 positive plasma cells
responds well to steroids
features of pancreatic tumours
ductal (85% of all neoplasms) M>F 5% 5yr survival most arise from acini acinar-ductal metaplasia
RF for pancreatic cancer
smoking
BMI and diet
chronic pancreatitis
DM
describe ductal carcinoma of the pancreas
arises from 2 types of dysplastic ductal lesions:
- pancreatic intraductal neoplasia (PanIN)
- intraductal mucinous papillary neoplasm (IMP)
K-Ras mutations in 95%
gritty and grey
invades adjacent structures
tumours at the head present earlier
describe metastasis of ductal carcinoma
direct - bile ducts, duodenum
lymphatic - LN
blood - liver
serosa - peritoneum
describe pancreatic endocrine neoplasms
usually non-secretory
contain neuroendocrine markers - eg chromogranin
can be associated with MEN1
insulinomas - hypoglycaemia
2 types of gallstone
cholesterol - may be single
usually radiolucent
pigment - contain calcium salts of unconjugated bilirubin
often multiple
radiopaque
complications of gallstones
bile duct obstruction
acute and chronic cholecystitis
gallbladder cancer
pancreatitis
features of gallbladder cancer
adenocarcinoma
90% associated with gallstones
uncommon
