Pathology of the GI Tract- Pancreas (1) Flashcards
what are three examples of pancreatic anomalies?
pancreatic divisum, annular pancreas, and ectopic pancreas
what is pancreatic divisum associated with?
chronic pancreatitis
what is annular pancreas associated with?
duodenal obstruction
what could ectopic pancreatic tissue lead to?
mucosal bleeding
what do acinar and ductal cells of the pancreas secrete as a protective mechanism?
trypsin inhibitors aka serine protease inhibitor Kazal type I (SPINK1)
why does hypercalcemia lead to pancreatitis?
calcium has a key role in trypsin regulation; trypsin autoactivation is favored when calcium levels are increased
what is the feature shared by most forms of hereditary pancreatitis?
a defect that increases or sustains the activity of trypsin
what are three common genes that are mutated that lead to recurring pancreatitis?
CFTR (loss of function), SPINK1 (loss of function), PRSS1 (gain of function)
what are possible sequelae of pancreatitis?
sterile pancreatic abscesses and pancreatic pseudocysts
what are two ominous complications associated with pancreatitis?
ARDS and renal failure
what is responsible for the scar tissue found in chronic pancreatitis?
TGF-beta, which is produced by activated macrophages
what can autoimmune pancreatitis mimic?
both types can mimic pancreatic carcinoma
what is helpful when making the diagnosis of chronic pancreatitis?
visualization of calcifications within the pancreas- dystrophic calcifications
what could result from chronic pancreatitis?
pseudocyst formation, pancreatic exocrine insufficiency/ weight loss; DM
what are pseudocysts of the pancreas?
they lack an epithelial lining; arise following a bout of acute pancreatitis
what are the complications associated with pseudocysts?
secondary infection or they may compress or even perforate into adjacent structures
pancreatic cancer has a higher incidence in what populations?
african americans, ashkenazi jews, japanese americans, and native hawaiian islanders
what is the strongest environmental influence on pancreatic cancer?
cigarette smoking
invasive pancreatic cancers arise from what?
non-invasive precursor lesions referred to as pancreatic intraepithelial neoplasia (PanIN)
what has been found to be a major cause of mutations in in PDA?
an aberrant methylation is a major cause of mutations
alterations of what 4 genes have been confirmed to be far more common than any other genes in PDAs?
KRAS, TP53, CDKN2A, and SMAD4
approximately 10% of patients with pancreatic cancer have a deleterious germline mutation in a cancer predisposition gene or report one or more first-degree relatives with pancreatic cancer; what gene mutation is the most common cause of familial pancreatic cancer?
BRCA2
what are two characteristic features of most pancreatic cancers?
most are adenocarcinomas and they elicit an intense desmoplastic response that results in the deposition of dense collagen
what contributes to the increased risk of thromboembolism in disseminated cancers aka Migratory thrombophlebitis?
tumor-associated inflammation and coagulation factors as well as procoagulants (e.g mucin)
