Diseases Flashcards
Pancreas Divisum
congenital; results from failure of the fetal duct system of the dorsal and ventral pancreatic primordia fuse in utero
Predisposition to chronic pancreatitis due relative stenosis of the nearly the entire pancrea draining through the minor papilla
Annular pancreas
occurs in utero when one portion of the ventral pancreatic primordium becomes fixed , while the other portion is strung around the doudenum
causes signs and symptoms of DUODENAL OBSTRUCTION
ectopic pancreas
embryological rests in the submucosa (most commonly found in the stomach and duodenum)
MECKEL DIVERTICULA
Histo: unremarkable exocrine pancreas, sometimes with islets of langerhans
Acute Pancreatitis
- Reversible
- two top causes: ALCOHOL(more common in men) And GALLSTONES (more common in women)!!
- morphology of acute:
- -> micro vascular leakage causing edema
- -> necrosis of fat by lipolytic enzymes (“chalky white”)- within gland and parapancreatic adipose
- -> acute inflammation
- -> proteolytic destruction of pancreatic parenchyma
- -> destruction of blood vessels with resulting hemorrhage
Hereditary pancreatitis
AD disorder causes by mutation in trypsinogen gene (PRSS1), affects the site that essential for auto-inactivation (since now active inappopriately will continue to activate other enzymes)
-40% chance of developing pancreatic carcinoma
3 proposed mechanisms of pancreatitis
1) Duct obstruction
2) Acinar cell injury
3) defective intracellular transport
Chronic pancreatitis
- Irreversible
- long term alcohol abuse is most common cause
- whatever the process is the cause. the result is parenchymal fibrosis
- TFG and PDGF induces the activation and proliferation of myofibroblasts , leading to fibrosis
- calcifications and dilated ducts
Pathological characterization of chronic pancreatitis
Parenchymal fibrosis, loss of acini with sparing of islets of langherans, and variable dilation of pancreatic ducts
- protein rich secretions found in ducts
- eventually islets of langherans will dissappear
congenital cysts
- non-neoplastic
- anomalous development of pancreatic duct
- TRUE CYST lined by EPITHELIAL LAYER
Pseudocysts
-non-neoplastic
LACK EPITHELIAL LAYER–> therefore not True cyst
-majority of cysts in pancreas still (75%)
-associated with pancreatitis
-usually solitary; can be within substance of pancreas nut more commonly in the periphery of the gland extending into the adipose tissue
-created by walls of fibrous granulation tissue that have encased regions of hemorrhagic fate necrosis (result is necrotic and hemorrhagic material within non-epithelialized cavity)
-up to 30 cm in diameter
serous cystadenoma
- almost always benign neopasms
- 2x as common in women vs men.
- composed of GLYCOGEN RICH, low cuboidal cells surrounding small cysts that contain clear thin fluid
mucinous cystic neoplasm
- almost always arise in women
- benign, borderline, or malignant (dependent on the presence or absence of invasion)
- filled with THICK TENACIOUS MUCIN
- lined by columnar mucinous epithelium overlying dense OVARIAN like stroma
Intraductal papillary mucinous neoplasm
- produce cysts that contain mucin and can be benign, borderline, or malignant
- more common in men
- more often involve head of pancreas rather than tail
- Rise in the main pancreatic duct (note most mucinous cystic neoplasms do not connect with main ducts)
- lack dense stroma overlying epithelium
Pancreatic carcinoma
-infiltrating ductal carcinomal of the pancreas
-one of the highest mortality rates of cancer
-strongest environmental factor is smoking
-multiple genes altered in any given carcinoma
(oncogene KRAS or p16 tumor suppressor gene)
-inherited predisposition to pancreatic cancer: Hereditary breast and ovarian cancer, Peutz-Jeghers syndrome (highest risk at 120 fold), hereditary pancreatitis
pancreatic carcinoma distribution
60%-head 20% - diffuse gland 15%-body 5%-tail (note the more distant to the head, can remain clinically silent longer due to lack of involvement of common bile duct)
