Ch 19 Robbins Flashcards
What is the exocrine pancreas composed of?
Acinar cells that secrete enzymes for digestion
What is the endocrine pancreas composed of?
Islets of Langerhans
What do the Islets of Langerhans secrete?
1) Insulin
2) Glucagon
3) Somatostatin
What is the most common congenital anomaly of the pancreas?
Pancreas divisum
Annular pancreas are band-like rings of normal pancreatic tissue that encircles the?
Second portion of the duodenum
Pancreatic agenesis is due to homozygous mutation of?
PDX1
Why is acute pancreatitis irreversible?
It is reversible
What are three initiating events that lead to pancreatic autodigestion?
1) Duct obstruction
2) Primary acinar cell injury
3) Defective intracellular transport of proenzymes within acinar cells
With pancreatic duct obstruction, lipase has potential for?
Local fat necrosis
What is a shared feature of most forms of hereditary pancreatitis?
Defect that increases the activity of trypsin
What does acute pancreatitis lead to morphologically?
1) Edema that leads to microvascular leakage
2) Fat necrosis
3) Destruction of pancreatic parenchyma
4) Interstitial hemorrhage
What levels are increased with acute pancreatitis in the first 24 hours?
What are increased within 72-96 hours?
1) Amylase
2) Lipase
Chronic pancreatitis is characterized as prolonged inflammation of the pancreas due to?
Irreversible destruction of exocrine and endocrine parenchyma
What population is chronic pancreatitis most often seen it?
What is the most common cause of it?
1) Middle aged males
2) Long term alcohol abuse
What fibrogenic inflammatory mediators are produced during chronic pancreatitis?
TGFβ and PDGF
What does autoimmune pancreatitis respond well to?
Steroid therapy
What are the most common pancreatic cysts?
Pseudocysts
What are large, well-circumscribed malignant neoplasms with solid and cystic components filled with hemorrhagic debris?
Solid pseudopapillary neoplasm
What mutation is associated with solid pseudopapillary neoplasm?
What does this mutation lead to?
1) CTNNB1 (β-catenin) oncogene mutation
2) Hyperactivation of WNT signaling
What is the 4th leading cause of cancer death in the USA due to it being on the most aggressive of the solid malignancies?
Infiltrating ductal adenocarcinoma (pancreatic carcinoma)
What is the strongest risk factor for infiltrating ductal adenocarcinoma?
Smoking
Adenocarcinoma of the head of pancreas produces?
This causes an elevation predominantly of?
This all results in the classic finding of?
1) Extrahepatic biliary obstruction
2) Direct bilirubin and Alkaline phosphatase
3) Painless jaundice
Where does infiltrating ductal adenocarcinoma metastasize to?
Liver and lungs
What is the most frequently altered oncogene in pancreatic cancers found on Chr 12p?
What is the most frequently inactivated tumor suppressor gene in pancreatic cancer found on Chr 9p?
What is inactivated in 55% of pancreatic cancers and found on Chr 18q, but rarely mutated in other cancers?
1) KRAS
2) CDKN2A
3) SMAD4
What is characterized by a syndrome of metastatic fat necrosis caused by the release of lipase into the circulation?
Acinar cell Carcinoma
Squamous islands admixed with acinar cells is a distinct microscopic appearance of?
Pancreatoblastoma
